Move toolchain resolution skyframe classes to a new package.

This helps clarify what is what in toolchain resolution.

Part of #18424.

PiperOrigin-RevId: 534169966
Change-Id: Ia34902646a493174b8f10bc8c0e87bf7eab31d04

src/main/java/com/google/devtools/build/lib/analysis/BUILD

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/BUILD b/src/main/java/com/google/devtools/build/lib/analysis/BUILD
index fede306..f1b0e1a 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/analysis/BUILD
@@ -1059,9 +1059,9 @@
         "//src/main/java/com/google/devtools/build/lib/cmdline",
         "//src/main/java/com/google/devtools/build/lib/concurrent",
         "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_and_data",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:toolchain_context_key",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:toolchain_exception",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:unloaded_toolchain_context",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_context_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:unloaded_toolchain_context",
         "//src/main/protobuf:failure_details_java_proto",
         "//third_party:auto_value",
         "//third_party:guava",
@@ -1181,7 +1181,7 @@
         ":config/toolchain_type_requirement",
         "//src/main/java/com/google/devtools/build/lib/analysis/platform",
         "//src/main/java/com/google/devtools/build/lib/cmdline",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:toolchain_context_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_context_key",
         "//third_party:guava",
     ],
 )

src/main/java/com/google/devtools/build/lib/analysis/ResolvedToolchainContext.java

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/ResolvedToolchainContext.java b/src/main/java/com/google/devtools/build/lib/analysis/ResolvedToolchainContext.java
index 767106c..8e6f08b 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/ResolvedToolchainContext.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/ResolvedToolchainContext.java
@@ -27,8 +27,8 @@
 import com.google.devtools.build.lib.concurrent.ThreadSafety.ThreadSafe;
 import com.google.devtools.build.lib.server.FailureDetails.Toolchain.Code;
 import com.google.devtools.build.lib.skyframe.ConfiguredTargetAndData;
-import com.google.devtools.build.lib.skyframe.ToolchainException;
-import com.google.devtools.build.lib.skyframe.UnloadedToolchainContext;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainException;
+import com.google.devtools.build.lib.skyframe.toolchains.UnloadedToolchainContext;
 import javax.annotation.Nullable;
 
 /**

src/main/java/com/google/devtools/build/lib/analysis/ToolchainContext.java

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/ToolchainContext.java b/src/main/java/com/google/devtools/build/lib/analysis/ToolchainContext.java
index f1778e3..702bbb7 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/ToolchainContext.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/ToolchainContext.java
@@ -17,7 +17,7 @@
 import com.google.devtools.build.lib.analysis.config.ToolchainTypeRequirement;
 import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
 import com.google.devtools.build.lib.cmdline.Label;
-import com.google.devtools.build.lib.skyframe.ToolchainContextKey;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainContextKey;
 
 /** Represents the data needed for a specific target's use of toolchains and platforms. */
 public interface ToolchainContext {

src/main/java/com/google/devtools/build/lib/analysis/producers/BUILD

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/producers/BUILD b/src/main/java/com/google/devtools/build/lib/analysis/producers/BUILD
index 8eb4648..6102876 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/producers/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/analysis/producers/BUILD
@@ -37,13 +37,13 @@
         "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_and_data",
         "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
         "//src/main/java/com/google/devtools/build/lib/skyframe:configured_value_creation_exception",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:no_matching_platform_exception",
         "//src/main/java/com/google/devtools/build/lib/skyframe:package_value",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:platform_lookup_util",
         "//src/main/java/com/google/devtools/build/lib/skyframe:rule_configured_target_value",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:toolchain_context_key",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:toolchain_exception",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:unloaded_toolchain_context",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:no_matching_platform_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:platform_lookup_util",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_context_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:unloaded_toolchain_context",
         "//src/main/java/com/google/devtools/build/lib/util:detailed_exit_code",
         "//src/main/java/com/google/devtools/build/skyframe",
         "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",

src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContext.java

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContext.java b/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContext.java
index c9ad0f2..2322b8a 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContext.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContext.java
@@ -16,7 +16,7 @@
 import com.google.auto.value.AutoValue;
 import com.google.devtools.build.lib.analysis.ToolchainCollection;
 import com.google.devtools.build.lib.analysis.config.ConfigConditions;
-import com.google.devtools.build.lib.skyframe.UnloadedToolchainContext;
+import com.google.devtools.build.lib.skyframe.toolchains.UnloadedToolchainContext;
 import javax.annotation.Nullable;
 
 /**

src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextError.java

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextError.java b/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextError.java
index 13c6d3c..faa2fdb 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextError.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextError.java
@@ -17,7 +17,7 @@
 import com.google.devtools.build.lib.analysis.constraints.IncompatibleTargetChecker.IncompatibleTargetException;
 import com.google.devtools.build.lib.packages.ConfiguredAttributeMapper.ValidationException;
 import com.google.devtools.build.lib.skyframe.ConfiguredValueCreationException;
-import com.google.devtools.build.lib.skyframe.ToolchainException;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainException;
 
 /** Tagged union of errors that can be encountered when creating the {@link DependencyContext}. */
 @AutoOneOf(DependencyContextError.Kind.class)

src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextProducer.java

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextProducer.java b/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextProducer.java
index 06b95fa..77a1c15 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextProducer.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextProducer.java
@@ -18,8 +18,8 @@
 import com.google.devtools.build.lib.analysis.config.ConfigConditions;
 import com.google.devtools.build.lib.events.ExtendedEventHandler;
 import com.google.devtools.build.lib.skyframe.ConfiguredValueCreationException;
-import com.google.devtools.build.lib.skyframe.ToolchainException;
-import com.google.devtools.build.lib.skyframe.UnloadedToolchainContext;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainException;
+import com.google.devtools.build.lib.skyframe.toolchains.UnloadedToolchainContext;
 import com.google.devtools.build.skyframe.state.StateMachine;
 import javax.annotation.Nullable;
 

src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextProducerWithCompatibilityCheck.java

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextProducerWithCompatibilityCheck.java b/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextProducerWithCompatibilityCheck.java
index ce3ae6e..18b44a6 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextProducerWithCompatibilityCheck.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/producers/DependencyContextProducerWithCompatibilityCheck.java
@@ -24,10 +24,10 @@
 import com.google.devtools.build.lib.packages.ConfiguredAttributeMapper.ValidationException;
 import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
 import com.google.devtools.build.lib.skyframe.ConfiguredValueCreationException;
-import com.google.devtools.build.lib.skyframe.PlatformLookupUtil.InvalidPlatformException;
 import com.google.devtools.build.lib.skyframe.RuleConfiguredTargetValue;
-import com.google.devtools.build.lib.skyframe.ToolchainException;
-import com.google.devtools.build.lib.skyframe.UnloadedToolchainContext;
+import com.google.devtools.build.lib.skyframe.toolchains.PlatformLookupUtil.InvalidPlatformException;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainException;
+import com.google.devtools.build.lib.skyframe.toolchains.UnloadedToolchainContext;
 import com.google.devtools.build.skyframe.state.StateMachine;
 import java.util.Optional;
 import javax.annotation.Nullable;

src/main/java/com/google/devtools/build/lib/analysis/producers/PlatformInfoProducer.java

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/producers/PlatformInfoProducer.java b/src/main/java/com/google/devtools/build/lib/analysis/producers/PlatformInfoProducer.java
index 0f5662f..88ff8e5 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/producers/PlatformInfoProducer.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/producers/PlatformInfoProducer.java
@@ -23,8 +23,8 @@
 import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
 import com.google.devtools.build.lib.skyframe.ConfiguredValueCreationException;
 import com.google.devtools.build.lib.skyframe.PackageValue;
-import com.google.devtools.build.lib.skyframe.PlatformLookupUtil;
-import com.google.devtools.build.lib.skyframe.PlatformLookupUtil.InvalidPlatformException;
+import com.google.devtools.build.lib.skyframe.toolchains.PlatformLookupUtil;
+import com.google.devtools.build.lib.skyframe.toolchains.PlatformLookupUtil.InvalidPlatformException;
 import com.google.devtools.build.skyframe.SkyValue;
 import com.google.devtools.build.skyframe.state.StateMachine;
 import javax.annotation.Nullable;

src/main/java/com/google/devtools/build/lib/analysis/producers/UnloadedToolchainContextsInputs.java

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/producers/UnloadedToolchainContextsInputs.java b/src/main/java/com/google/devtools/build/lib/analysis/producers/UnloadedToolchainContextsInputs.java
index 90ce841..868deac 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/producers/UnloadedToolchainContextsInputs.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/producers/UnloadedToolchainContextsInputs.java
@@ -17,7 +17,7 @@
 import com.google.common.collect.ImmutableMap;
 import com.google.devtools.build.lib.analysis.ExecGroupCollection;
 import com.google.devtools.build.lib.packages.ExecGroup;
-import com.google.devtools.build.lib.skyframe.ToolchainContextKey;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainContextKey;
 import javax.annotation.Nullable;
 
 /** Collates inputs for the {@link UnloadedToolchainContextsProducer}. */

src/main/java/com/google/devtools/build/lib/analysis/producers/UnloadedToolchainContextsProducer.java

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/producers/UnloadedToolchainContextsProducer.java b/src/main/java/com/google/devtools/build/lib/analysis/producers/UnloadedToolchainContextsProducer.java
index 4d618ed..f8369cf 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/producers/UnloadedToolchainContextsProducer.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/producers/UnloadedToolchainContextsProducer.java
@@ -18,10 +18,10 @@
 import com.google.devtools.build.lib.analysis.ToolchainCollection;
 import com.google.devtools.build.lib.events.ExtendedEventHandler;
 import com.google.devtools.build.lib.packages.ExecGroup;
-import com.google.devtools.build.lib.skyframe.NoMatchingPlatformException;
-import com.google.devtools.build.lib.skyframe.ToolchainContextKey;
-import com.google.devtools.build.lib.skyframe.ToolchainException;
-import com.google.devtools.build.lib.skyframe.UnloadedToolchainContext;
+import com.google.devtools.build.lib.skyframe.toolchains.NoMatchingPlatformException;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainContextKey;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainException;
+import com.google.devtools.build.lib.skyframe.toolchains.UnloadedToolchainContext;
 import com.google.devtools.build.skyframe.SkyValue;
 import com.google.devtools.build.skyframe.state.StateMachine;
 import java.util.Map;

src/main/java/com/google/devtools/build/lib/query2/BUILD

diff --git a/src/main/java/com/google/devtools/build/lib/query2/BUILD b/src/main/java/com/google/devtools/build/lib/query2/BUILD
index 01a9a30..3c493cd 100644
--- a/src/main/java/com/google/devtools/build/lib/query2/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/query2/BUILD
@@ -103,12 +103,12 @@
         "//src/main/java/com/google/devtools/build/lib/skyframe:sky_functions",
         "//src/main/java/com/google/devtools/build/lib/skyframe:skyframe_cluster",
         "//src/main/java/com/google/devtools/build/lib/skyframe:target_pattern_value",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:toolchain_context_key",
         "//src/main/java/com/google/devtools/build/lib/skyframe:transitive_traversal_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe:traversal_info_root_package_extractor",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:unloaded_toolchain_context",
         "//src/main/java/com/google/devtools/build/lib/skyframe:workspace_name_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe/actiongraph/v2:actiongraph_v2",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_context_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:unloaded_toolchain_context",
         "//src/main/java/com/google/devtools/build/lib/supplier",
         "//src/main/java/com/google/devtools/build/lib/util",
         "//src/main/java/com/google/devtools/build/lib/util:command",

src/main/java/com/google/devtools/build/lib/query2/cquery/ConfiguredTargetAccessor.java

diff --git a/src/main/java/com/google/devtools/build/lib/query2/cquery/ConfiguredTargetAccessor.java b/src/main/java/com/google/devtools/build/lib/query2/cquery/ConfiguredTargetAccessor.java
index f356d3e..0698fd7 100644
--- a/src/main/java/com/google/devtools/build/lib/query2/cquery/ConfiguredTargetAccessor.java
+++ b/src/main/java/com/google/devtools/build/lib/query2/cquery/ConfiguredTargetAccessor.java
@@ -45,8 +45,8 @@
 import com.google.devtools.build.lib.server.FailureDetails.ConfigurableQuery;
 import com.google.devtools.build.lib.skyframe.BuildConfigurationKey;
 import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
-import com.google.devtools.build.lib.skyframe.ToolchainContextKey;
-import com.google.devtools.build.lib.skyframe.UnloadedToolchainContext;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainContextKey;
+import com.google.devtools.build.lib.skyframe.toolchains.UnloadedToolchainContext;
 import com.google.devtools.build.skyframe.WalkableGraph;
 import java.util.List;
 import java.util.Map;

src/main/java/com/google/devtools/build/lib/skyframe/AbstractLabelCycleReporter.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/AbstractLabelCycleReporter.java b/src/main/java/com/google/devtools/build/lib/skyframe/AbstractLabelCycleReporter.java
index d0eaf0a..7d82132 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/AbstractLabelCycleReporter.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/AbstractLabelCycleReporter.java
@@ -35,7 +35,7 @@
 import java.util.function.Predicate;
 
 /** Reports cycles between skyframe values whose keys contains {@link Label}s. */
-abstract class AbstractLabelCycleReporter implements CyclesReporter.SingleCycleReporter {
+public abstract class AbstractLabelCycleReporter implements CyclesReporter.SingleCycleReporter {
 
   private final PackageProvider packageProvider;
 
@@ -131,7 +131,7 @@
   }
 
   /** Prints the SkyKey-s in cycle into cycleMessage using the print function. */
-  static SkyKey printCycle(
+  public static SkyKey printCycle(
       ImmutableList<SkyKey> cycle,
       StringBuilder cycleMessage,
       Function<Object, String> printFunction) {

src/main/java/com/google/devtools/build/lib/skyframe/AspectFunction.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/AspectFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/AspectFunction.java
index c64d876..5a10c2f 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/AspectFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/AspectFunction.java
@@ -81,6 +81,8 @@
 import com.google.devtools.build.lib.skyframe.AspectKeyCreator.AspectKey;
 import com.google.devtools.build.lib.skyframe.BzlLoadFunction.BzlLoadFailedException;
 import com.google.devtools.build.lib.skyframe.SkyframeExecutor.BuildViewProvider;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainException;
+import com.google.devtools.build.lib.skyframe.toolchains.UnloadedToolchainContext;
 import com.google.devtools.build.lib.util.OrderedSetMultimap;
 import com.google.devtools.build.skyframe.SkyFunction;
 import com.google.devtools.build.skyframe.SkyFunction.Environment.SkyKeyComputeState;

src/main/java/com/google/devtools/build/lib/skyframe/BUILD

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/BUILD b/src/main/java/com/google/devtools/build/lib/skyframe/BUILD
index 0bcd731..7d20ece 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/BUILD
@@ -14,6 +14,7 @@
         "//src/main/java/com/google/devtools/build/lib/skyframe/proto:srcs",
         "//src/main/java/com/google/devtools/build/lib/skyframe/rewinding:srcs",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization:srcs",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:srcs",
     ],
     visibility = ["//src:__subpackages__"],
 )
@@ -37,7 +38,6 @@
         "CompletionFunction.java",
         "ConfiguredTargetEvaluationExceptions.java",
         "ConfiguredTargetFunction.java",
-        "ConstraintValueLookupUtil.java",
         "CoverageReportFunction.java",
         "DirectoryListingStateFunction.java",
         "DirtinessCheckerUtils.java",
@@ -51,15 +51,8 @@
         "PlatformMappingFunction.java",
         "PrepareDepsOfPatternFunction.java",
         "PrerequisiteProducer.java",
-        "RegisteredExecutionPlatformsFunction.java",
-        "RegisteredExecutionPlatformsValue.java",
-        "RegisteredToolchainsCycleReporter.java",
-        "RegisteredToolchainsFunction.java",
-        "RegisteredToolchainsValue.java",
         "SequencedSkyframeExecutor.java",
         "SequencedSkyframeExecutorFactory.java",
-        "SingleToolchainResolutionFunction.java",
-        "SingleToolchainResolutionValue.java",
         "SkyframeActionExecutor.java",
         "SkyframeAnalysisAndExecutionResult.java",
         "SkyframeAnalysisResult.java",
@@ -77,15 +70,12 @@
         "TargetPatternFunction.java",
         "TargetPatternPhaseFunction.java",
         "TestCompletionFunction.java",
-        "ToolchainResolutionFunction.java",
-        "ToolchainTypeLookupUtil.java",
         "TopLevelActionLookupConflictFindingFunction.java",
         "ToplevelStarlarkAspectFunction.java",
         "TransitiveTargetFunction.java",
         "WorkspaceFileFunction.java",
     ],
     deps = [
-        ":abstract_label_cycle_reporter",
         ":action_artifact_cycle_reporter",
         ":action_environment_function",
         ":action_execution_inactivity_watchdog",
@@ -152,7 +142,6 @@
         ":local_repository_lookup_value",
         ":map_as_package_roots",
         ":metadata_consumer_for_metrics",
-        ":no_matching_platform_data",
         ":node_dropping_inconsistency_receiver",
         ":package_error_function",
         ":package_error_message_function",
@@ -163,7 +152,6 @@
         ":package_roots_no_symlink_creation",
         ":package_value",
         ":pattern_expanding_error",
-        ":platform_lookup_util",
         ":precomputed_function",
         ":precomputed_value",
         ":prepare_deps_of_pattern_value",
@@ -196,7 +184,6 @@
         ":target_loading_util",
         ":target_pattern_error_function",
         ":target_pattern_phase_value",
-        ":target_pattern_util",
         ":target_pattern_value",
         ":target_patterns_result_builder",
         ":test_completion_value",
@@ -204,8 +191,6 @@
         ":test_expansion_function",
         ":tests_for_target_pattern_function",
         ":tests_for_target_pattern_value",
-        ":toolchain_context_key",
-        ":toolchain_exception",
         ":top_level_action_lookup_key_wrapper",
         ":top_level_aspects_value",
         ":top_level_status_events",
@@ -215,8 +200,6 @@
         ":transitive_traversal_function",
         ":transitive_traversal_value",
         ":tree_artifact_value",
-        ":unloaded_toolchain_context",
-        ":unloaded_toolchain_context_impl",
         ":workspace_info",
         ":workspace_info_receiver",
         ":workspace_name_function",
@@ -288,10 +271,8 @@
         "//src/main/java/com/google/devtools/build/lib/analysis:view_creation_failed_exception",
         "//src/main/java/com/google/devtools/build/lib/analysis:workspace_status_action",
         "//src/main/java/com/google/devtools/build/lib/analysis/platform",
-        "//src/main/java/com/google/devtools/build/lib/analysis/platform:utils",
         "//src/main/java/com/google/devtools/build/lib/analysis/producers",
         "//src/main/java/com/google/devtools/build/lib/bazel/bzlmod:common",
-        "//src/main/java/com/google/devtools/build/lib/bazel/bzlmod:exception",
         "//src/main/java/com/google/devtools/build/lib/bazel/bzlmod:module_extension",
         "//src/main/java/com/google/devtools/build/lib/bazel/bzlmod:repo_rule_creator",
         "//src/main/java/com/google/devtools/build/lib/bazel/bzlmod:repo_rule_value",
@@ -340,6 +321,14 @@
         "//src/main/java/com/google/devtools/build/lib/skyframe/rewinding:rewindable_graph_inconsistency_receiver",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec:serialization-constant",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:registered_execution_platforms_function",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:registered_toolchains_cycle_reporter",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:registered_toolchains_function",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:single_toolchain_resolution_function",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_context_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_resolution_function",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:unloaded_toolchain_context",
         "//src/main/java/com/google/devtools/build/lib/util",
         "//src/main/java/com/google/devtools/build/lib/util:TestType",
         "//src/main/java/com/google/devtools/build/lib/util:abrupt_exit_exception",
@@ -1632,28 +1621,6 @@
 )
 
 java_library(
-    name = "no_matching_platform_data",
-    srcs = ["NoMatchingPlatformData.java"],
-    deps = [
-        ":configured_target_key",
-        "//src/main/java/com/google/devtools/build/lib/analysis:config/toolchain_type_requirement",
-        "//src/main/java/com/google/devtools/build/lib/cmdline",
-        "//third_party:auto_value",
-        "//third_party:guava",
-    ],
-)
-
-java_library(
-    name = "no_matching_platform_exception",
-    srcs = ["NoMatchingPlatformException.java"],
-    deps = [
-        ":no_matching_platform_data",
-        ":toolchain_exception",
-        "//src/main/protobuf:failure_details_java_proto",
-    ],
-)
-
-java_library(
     name = "output_store",
     srcs = ["OutputStore.java"],
     deps = [
@@ -1835,29 +1802,6 @@
 )
 
 java_library(
-    name = "platform_lookup_util",
-    srcs = ["PlatformLookupUtil.java"],
-    deps = [
-        ":configured_target_key",
-        ":configured_value_creation_exception",
-        ":package_value",
-        ":toolchain_exception",
-        "//src/main/java/com/google/devtools/build/lib/actions",
-        "//src/main/java/com/google/devtools/build/lib/analysis:configured_target",
-        "//src/main/java/com/google/devtools/build/lib/analysis:configured_target_value",
-        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
-        "//src/main/java/com/google/devtools/build/lib/analysis/platform:utils",
-        "//src/main/java/com/google/devtools/build/lib/bugreport",
-        "//src/main/java/com/google/devtools/build/lib/cmdline",
-        "//src/main/java/com/google/devtools/build/lib/packages",
-        "//src/main/java/com/google/devtools/build/skyframe",
-        "//src/main/protobuf:failure_details_java_proto",
-        "//third_party:guava",
-        "//third_party:jsr305",
-    ],
-)
-
-java_library(
     name = "precomputed_function",
     srcs = ["PrecomputedFunction.java"],
     deps = [
@@ -2665,33 +2609,6 @@
 )
 
 java_library(
-    name = "toolchain_context_key",
-    srcs = ["ToolchainContextKey.java"],
-    deps = [
-        ":build_configuration",
-        ":sky_functions",
-        "//src/main/java/com/google/devtools/build/lib/analysis:config/toolchain_type_requirement",
-        "//src/main/java/com/google/devtools/build/lib/cmdline",
-        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
-        "//third_party:auto_value",
-        "//third_party:guava",
-    ],
-)
-
-java_library(
-    name = "toolchain_exception",
-    srcs = ["ToolchainException.java"],
-    deps = [
-        ":configured_value_creation_exception",
-        ":detailed_exceptions",
-        "//src/main/java/com/google/devtools/build/lib/analysis:target_and_configuration",
-        "//src/main/java/com/google/devtools/build/lib/util:detailed_exit_code",
-        "//src/main/protobuf:failure_details_java_proto",
-        "//third_party:guava",
-    ],
-)
-
-java_library(
     name = "top_level_action_lookup_key_wrapper",
     srcs = ["TopLevelActionLookupKeyWrapper.java"],
     deps = [
@@ -2916,37 +2833,6 @@
 )
 
 java_library(
-    name = "unloaded_toolchain_context",
-    srcs = ["UnloadedToolchainContext.java"],
-    deps = [
-        ":no_matching_platform_data",
-        "//src/main/java/com/google/devtools/build/lib/analysis:toolchain_context",
-        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
-        "//src/main/java/com/google/devtools/build/lib/cmdline",
-        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
-        "//third_party:guava",
-        "//third_party:jsr305",
-    ],
-)
-
-java_library(
-    name = "unloaded_toolchain_context_impl",
-    srcs = ["UnloadedToolchainContextImpl.java"],
-    deps = [
-        ":no_matching_platform_data",
-        ":toolchain_context_key",
-        ":unloaded_toolchain_context",
-        "//src/main/java/com/google/devtools/build/lib/analysis:config/toolchain_type_requirement",
-        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
-        "//src/main/java/com/google/devtools/build/lib/cmdline",
-        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
-        "//third_party:auto_value",
-        "//third_party:guava",
-        "//third_party:jsr305",
-    ],
-)
-
-java_library(
     name = "workspace_info",
     srcs = ["WorkspaceInfoFromDiff.java"],
 )

src/main/java/com/google/devtools/build/lib/skyframe/ConfiguredTargetFunction.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ConfiguredTargetFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/ConfiguredTargetFunction.java
index 15606b7..766279b 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/ConfiguredTargetFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/ConfiguredTargetFunction.java
@@ -58,6 +58,8 @@
 import com.google.devtools.build.lib.skyframe.ConfiguredTargetEvaluationExceptions.ReportedException;
 import com.google.devtools.build.lib.skyframe.ConfiguredTargetEvaluationExceptions.UnreportedException;
 import com.google.devtools.build.lib.skyframe.SkyframeExecutor.BuildViewProvider;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainException;
+import com.google.devtools.build.lib.skyframe.toolchains.UnloadedToolchainContext;
 import com.google.devtools.build.lib.util.DetailedExitCode;
 import com.google.devtools.build.lib.util.DetailedExitCode.DetailedExitCodeComparator;
 import com.google.devtools.build.lib.util.OrderedSetMultimap;

src/main/java/com/google/devtools/build/lib/skyframe/PrerequisiteProducer.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/PrerequisiteProducer.java b/src/main/java/com/google/devtools/build/lib/skyframe/PrerequisiteProducer.java
index 7886822..d08854c 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/PrerequisiteProducer.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/PrerequisiteProducer.java
@@ -77,6 +77,9 @@
 import com.google.devtools.build.lib.server.FailureDetails.FailureDetail;
 import com.google.devtools.build.lib.skyframe.ConfiguredTargetEvaluationExceptions.ReportedException;
 import com.google.devtools.build.lib.skyframe.ConfiguredTargetEvaluationExceptions.UnreportedException;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainContextKey;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainException;
+import com.google.devtools.build.lib.skyframe.toolchains.UnloadedToolchainContext;
 import com.google.devtools.build.lib.util.DetailedExitCode;
 import com.google.devtools.build.lib.util.DetailedExitCode.DetailedExitCodeComparator;
 import com.google.devtools.build.lib.util.OrderedSetMultimap;

src/main/java/com/google/devtools/build/lib/skyframe/SkyFunctions.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SkyFunctions.java b/src/main/java/com/google/devtools/build/lib/skyframe/SkyFunctions.java
index 9eb8b4f..b109eec 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SkyFunctions.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SkyFunctions.java
@@ -123,11 +123,11 @@
       SkyFunctionName.createHermetic("ACTION_TEMPLATE_EXPANSION");
   public static final SkyFunctionName LOCAL_REPOSITORY_LOOKUP =
       SkyFunctionName.createHermetic("LOCAL_REPOSITORY_LOOKUP");
-  static final SkyFunctionName REGISTERED_EXECUTION_PLATFORMS =
+  public static final SkyFunctionName REGISTERED_EXECUTION_PLATFORMS =
       SkyFunctionName.createHermetic("REGISTERED_EXECUTION_PLATFORMS");
-  static final SkyFunctionName REGISTERED_TOOLCHAINS =
+  public static final SkyFunctionName REGISTERED_TOOLCHAINS =
       SkyFunctionName.createHermetic("REGISTERED_TOOLCHAINS");
-  static final SkyFunctionName SINGLE_TOOLCHAIN_RESOLUTION =
+  public static final SkyFunctionName SINGLE_TOOLCHAIN_RESOLUTION =
       SkyFunctionName.createHermetic("SINGLE_TOOLCHAIN_RESOLUTION");
   public static final SkyFunctionName TOOLCHAIN_RESOLUTION =
       SkyFunctionName.createHermetic("TOOLCHAIN_RESOLUTION");

src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java
index 178ecb1..b4eaf60 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/SkyframeExecutor.java
@@ -199,6 +199,11 @@
 import com.google.devtools.build.lib.skyframe.SkyframeActionExecutor.ActionCompletedReceiver;
 import com.google.devtools.build.lib.skyframe.SkyframeActionExecutor.ProgressSupplier;
 import com.google.devtools.build.lib.skyframe.TopLevelStatusEvents.SomeExecutionStartedEvent;
+import com.google.devtools.build.lib.skyframe.toolchains.RegisteredExecutionPlatformsFunction;
+import com.google.devtools.build.lib.skyframe.toolchains.RegisteredToolchainsCycleReporter;
+import com.google.devtools.build.lib.skyframe.toolchains.RegisteredToolchainsFunction;
+import com.google.devtools.build.lib.skyframe.toolchains.SingleToolchainResolutionFunction;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainResolutionFunction;
 import com.google.devtools.build.lib.util.AbruptExitException;
 import com.google.devtools.build.lib.util.DetailedExitCode;
 import com.google.devtools.build.lib.util.Pair;

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/BUILD

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/BUILD b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/BUILD
new file mode 100644
index 0000000..c62a9dc
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/BUILD
@@ -0,0 +1,349 @@
+load("@rules_java//java:defs.bzl", "java_library")
+
+package(
+    default_applicable_licenses = ["//:license"],
+    default_visibility = ["//src:__subpackages__"],
+)
+
+filegroup(
+    name = "srcs",
+    srcs = glob(["**"]),
+    visibility = ["//src:__subpackages__"],
+)
+
+java_library(
+    name = "constraint_value_lookup_util",
+    srcs = ["ConstraintValueLookupUtil.java"],
+    deps = [
+        ":toolchain_exception",
+        "//src/main/java/com/google/devtools/build/lib/actions",
+        "//src/main/java/com/google/devtools/build/lib/analysis:configured_target",
+        "//src/main/java/com/google/devtools/build/lib/analysis:configured_target_value",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform:utils",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/packages",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_value_creation_exception",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/protobuf:failure_details_java_proto",
+        "//third_party:guava",
+        "//third_party:jsr305",
+    ],
+)
+
+java_library(
+    name = "no_matching_platform_data",
+    srcs = ["NoMatchingPlatformData.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/analysis:config/toolchain_type_requirement",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//third_party:auto_value",
+        "//third_party:guava",
+    ],
+)
+
+java_library(
+    name = "no_matching_platform_exception",
+    srcs = ["NoMatchingPlatformException.java"],
+    deps = [
+        ":no_matching_platform_data",
+        ":toolchain_exception",
+        "//src/main/protobuf:failure_details_java_proto",
+    ],
+)
+
+java_library(
+    name = "platform_lookup_util",
+    srcs = ["PlatformLookupUtil.java"],
+    deps = [
+        ":toolchain_exception",
+        "//src/main/java/com/google/devtools/build/lib/actions",
+        "//src/main/java/com/google/devtools/build/lib/analysis:configured_target",
+        "//src/main/java/com/google/devtools/build/lib/analysis:configured_target_value",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform:utils",
+        "//src/main/java/com/google/devtools/build/lib/bugreport",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/packages",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_value_creation_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:package_value",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/protobuf:failure_details_java_proto",
+        "//third_party:guava",
+        "//third_party:jsr305",
+    ],
+)
+
+java_library(
+    name = "registered_execution_platforms_function",
+    srcs = ["RegisteredExecutionPlatformsFunction.java"],
+    deps = [
+        ":platform_lookup_util",
+        ":registered_execution_platforms_value",
+        ":toolchain_exception",
+        "//src/main/java/com/google/devtools/build/lib/analysis:config/build_configuration",
+        "//src/main/java/com/google/devtools/build/lib/analysis:configured_target",
+        "//src/main/java/com/google/devtools/build/lib/analysis:configured_target_value",
+        "//src/main/java/com/google/devtools/build/lib/analysis:platform_configuration",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform:utils",
+        "//src/main/java/com/google/devtools/build/lib/bazel/bzlmod:resolution",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/packages",
+        "//src/main/java/com/google/devtools/build/lib/packages/semantics",
+        "//src/main/java/com/google/devtools/build/lib/pkgcache",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_value_creation_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:package_value",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:precomputed_value",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:repository_mapping_value",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:sane_analysis_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:target_pattern_util",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec:serialization-constant",
+        "//src/main/java/com/google/devtools/build/lib/util:detailed_exit_code",
+        "//src/main/java/com/google/devtools/build/lib/vfs:pathfragment",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//src/main/java/net/starlark/java/eval",
+        "//src/main/protobuf:failure_details_java_proto",
+        "//third_party:guava",
+        "//third_party:jsr305",
+    ],
+)
+
+java_library(
+    name = "registered_execution_platforms_value",
+    srcs = ["RegisteredExecutionPlatformsValue.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/skyframe:build_configuration",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:sky_functions",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//third_party:auto_value",
+        "//third_party:guava",
+    ],
+)
+
+java_library(
+    name = "registered_toolchains_cycle_reporter",
+    srcs = ["RegisteredToolchainsCycleReporter.java"],
+    deps = [
+        ":registered_toolchains_value",
+        ":single_toolchain_resolution_value",
+        ":toolchain_context_key",
+        "//src/main/java/com/google/devtools/build/lib/analysis:config/toolchain_type_requirement",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/events",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:abstract_label_cycle_reporter",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:sky_functions",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//third_party:guava",
+    ],
+)
+
+java_library(
+    name = "registered_toolchains_function",
+    srcs = ["RegisteredToolchainsFunction.java"],
+    deps = [
+        ":registered_toolchains_value",
+        ":toolchain_exception",
+        "//src/main/java/com/google/devtools/build/lib/actions:action_lookup_key",
+        "//src/main/java/com/google/devtools/build/lib/analysis:config/build_configuration",
+        "//src/main/java/com/google/devtools/build/lib/analysis:configured_target",
+        "//src/main/java/com/google/devtools/build/lib/analysis:configured_target_value",
+        "//src/main/java/com/google/devtools/build/lib/analysis:platform_configuration",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform:utils",
+        "//src/main/java/com/google/devtools/build/lib/bazel/bzlmod:exception",
+        "//src/main/java/com/google/devtools/build/lib/bazel/bzlmod:resolution",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/packages",
+        "//src/main/java/com/google/devtools/build/lib/packages/semantics",
+        "//src/main/java/com/google/devtools/build/lib/pkgcache",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_value_creation_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:package_value",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:precomputed_value",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:repository_mapping_value",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:target_pattern_util",
+        "//src/main/java/com/google/devtools/build/lib/vfs:pathfragment",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//src/main/java/net/starlark/java/eval",
+        "//src/main/protobuf:failure_details_java_proto",
+        "//third_party:guava",
+        "//third_party:jsr305",
+    ],
+)
+
+java_library(
+    name = "registered_toolchains_value",
+    srcs = ["RegisteredToolchainsValue.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:build_configuration",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:sky_functions",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//third_party:auto_value",
+        "//third_party:guava",
+    ],
+)
+
+java_library(
+    name = "single_toolchain_resolution_function",
+    srcs = ["SingleToolchainResolutionFunction.java"],
+    deps = [
+        ":platform_lookup_util",
+        ":registered_toolchains_function",
+        ":registered_toolchains_value",
+        ":single_toolchain_resolution_value",
+        "//src/main/java/com/google/devtools/build/lib/analysis:config/build_configuration",
+        "//src/main/java/com/google/devtools/build/lib/analysis:config/config_matching_provider",
+        "//src/main/java/com/google/devtools/build/lib/analysis:config/toolchain_type_requirement",
+        "//src/main/java/com/google/devtools/build/lib/analysis:platform_configuration",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/events",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//third_party:error_prone_annotations",
+        "//third_party:guava",
+        "//third_party:jsr305",
+    ],
+)
+
+java_library(
+    name = "single_toolchain_resolution_value",
+    srcs = ["SingleToolchainResolutionValue.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/analysis:config/toolchain_type_requirement",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:build_configuration",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:sky_functions",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//third_party:auto_value",
+        "//third_party:guava",
+    ],
+)
+
+java_library(
+    name = "toolchain_context_key",
+    srcs = ["ToolchainContextKey.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/analysis:config/toolchain_type_requirement",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:build_configuration",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:sky_functions",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//third_party:auto_value",
+        "//third_party:guava",
+    ],
+)
+
+java_library(
+    name = "toolchain_exception",
+    srcs = ["ToolchainException.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/analysis:target_and_configuration",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_value_creation_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:detailed_exceptions",
+        "//src/main/java/com/google/devtools/build/lib/util:detailed_exit_code",
+        "//src/main/protobuf:failure_details_java_proto",
+        "//third_party:guava",
+    ],
+)
+
+java_library(
+    name = "toolchain_resolution_function",
+    srcs = ["ToolchainResolutionFunction.java"],
+    deps = [
+        ":constraint_value_lookup_util",
+        ":no_matching_platform_data",
+        ":platform_lookup_util",
+        ":registered_execution_platforms_function",
+        ":registered_execution_platforms_value",
+        ":registered_toolchains_function",
+        ":single_toolchain_resolution_value",
+        ":toolchain_context_key",
+        ":toolchain_exception",
+        ":toolchain_type_lookup_util",
+        ":unloaded_toolchain_context",
+        ":unloaded_toolchain_context_impl",
+        "//src/main/java/com/google/devtools/build/lib/analysis:config/build_configuration",
+        "//src/main/java/com/google/devtools/build/lib/analysis:config/toolchain_type_requirement",
+        "//src/main/java/com/google/devtools/build/lib/analysis:platform_configuration",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/events",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:build_configuration",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//src/main/protobuf:failure_details_java_proto",
+        "//third_party:auto_value",
+        "//third_party:guava",
+        "//third_party:jsr305",
+    ],
+)
+
+java_library(
+    name = "toolchain_type_lookup_util",
+    srcs = ["ToolchainTypeLookupUtil.java"],
+    deps = [
+        ":toolchain_exception",
+        "//src/main/java/com/google/devtools/build/lib/actions",
+        "//src/main/java/com/google/devtools/build/lib/analysis:configured_target",
+        "//src/main/java/com/google/devtools/build/lib/analysis:configured_target_value",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform:utils",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/packages",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_value_creation_exception",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/protobuf:failure_details_java_proto",
+        "//third_party:guava",
+        "//third_party:jsr305",
+    ],
+)
+
+java_library(
+    name = "unloaded_toolchain_context",
+    srcs = ["UnloadedToolchainContext.java"],
+    deps = [
+        ":no_matching_platform_data",
+        "//src/main/java/com/google/devtools/build/lib/analysis:toolchain_context",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//third_party:guava",
+        "//third_party:jsr305",
+    ],
+)
+
+java_library(
+    name = "unloaded_toolchain_context_impl",
+    srcs = ["UnloadedToolchainContextImpl.java"],
+    deps = [
+        ":no_matching_platform_data",
+        ":toolchain_context_key",
+        ":unloaded_toolchain_context",
+        "//src/main/java/com/google/devtools/build/lib/analysis:config/toolchain_type_requirement",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//third_party:auto_value",
+        "//third_party:guava",
+        "//third_party:jsr305",
+    ],
+)

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ConstraintValueLookupUtil.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ConstraintValueLookupUtil.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ConstraintValueLookupUtil.java
similarity index 95%
rename from src/main/java/com/google/devtools/build/lib/skyframe/ConstraintValueLookupUtil.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ConstraintValueLookupUtil.java
index 3b36b91..b7316e6 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/ConstraintValueLookupUtil.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ConstraintValueLookupUtil.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import com.google.common.collect.Iterables;
 import com.google.devtools.build.lib.actions.MutableActionGraph.ActionConflictException;
@@ -23,6 +23,8 @@
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.packages.NoSuchThingException;
 import com.google.devtools.build.lib.server.FailureDetails.Toolchain.Code;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.ConfiguredValueCreationException;
 import com.google.devtools.build.skyframe.SkyFunction.Environment;
 import com.google.devtools.build.skyframe.SkyframeLookupResult;
 import java.util.ArrayList;

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/NoMatchingPlatformData.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/NoMatchingPlatformData.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/NoMatchingPlatformData.java
similarity index 95%
rename from src/main/java/com/google/devtools/build/lib/skyframe/NoMatchingPlatformData.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/NoMatchingPlatformData.java
index 12859d5..ec9b5c9 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/NoMatchingPlatformData.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/NoMatchingPlatformData.java
@@ -11,7 +11,7 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static java.util.stream.Collectors.joining;
 
@@ -20,6 +20,7 @@
 import com.google.common.collect.ImmutableSet;
 import com.google.devtools.build.lib.analysis.config.ToolchainTypeRequirement;
 import com.google.devtools.build.lib.cmdline.Label;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
 
 /** Contains information related to missing execution platform. */
 @AutoValue

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/NoMatchingPlatformException.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/NoMatchingPlatformException.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/NoMatchingPlatformException.java
similarity index 94%
rename from src/main/java/com/google/devtools/build/lib/skyframe/NoMatchingPlatformException.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/NoMatchingPlatformException.java
index 4f9dc64..64002b8 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/NoMatchingPlatformException.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/NoMatchingPlatformException.java
@@ -11,7 +11,7 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import com.google.devtools.build.lib.server.FailureDetails;
 

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/PlatformLookupUtil.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/PlatformLookupUtil.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/PlatformLookupUtil.java
similarity index 96%
rename from src/main/java/com/google/devtools/build/lib/skyframe/PlatformLookupUtil.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/PlatformLookupUtil.java
index 764cdcd..4523178 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/PlatformLookupUtil.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/PlatformLookupUtil.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static com.google.common.collect.ImmutableSet.toImmutableSet;
 
@@ -34,6 +34,9 @@
 import com.google.devtools.build.lib.packages.Rule;
 import com.google.devtools.build.lib.packages.Target;
 import com.google.devtools.build.lib.server.FailureDetails.Toolchain.Code;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.ConfiguredValueCreationException;
+import com.google.devtools.build.lib.skyframe.PackageValue;
 import com.google.devtools.build.skyframe.SkyFunction.Environment;
 import com.google.devtools.build.skyframe.SkyframeLookupResult;
 import java.util.HashMap;

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredExecutionPlatformsFunction.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/RegisteredExecutionPlatformsFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredExecutionPlatformsFunction.java
similarity index 94%
rename from src/main/java/com/google/devtools/build/lib/skyframe/RegisteredExecutionPlatformsFunction.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredExecutionPlatformsFunction.java
index e0ca835..39dcd01 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/RegisteredExecutionPlatformsFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredExecutionPlatformsFunction.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static com.google.common.collect.ImmutableList.toImmutableList;
 
@@ -41,9 +41,16 @@
 import com.google.devtools.build.lib.server.FailureDetails.Analysis.Code;
 import com.google.devtools.build.lib.server.FailureDetails.FailureDetail;
 import com.google.devtools.build.lib.server.FailureDetails.Toolchain;
-import com.google.devtools.build.lib.skyframe.PlatformLookupUtil.InvalidPlatformException;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.ConfiguredValueCreationException;
+import com.google.devtools.build.lib.skyframe.PackageValue;
+import com.google.devtools.build.lib.skyframe.PrecomputedValue;
+import com.google.devtools.build.lib.skyframe.RepositoryMappingValue;
+import com.google.devtools.build.lib.skyframe.SaneAnalysisException;
+import com.google.devtools.build.lib.skyframe.TargetPatternUtil;
 import com.google.devtools.build.lib.skyframe.TargetPatternUtil.InvalidTargetPatternException;
 import com.google.devtools.build.lib.skyframe.serialization.autocodec.SerializationConstant;
+import com.google.devtools.build.lib.skyframe.toolchains.PlatformLookupUtil.InvalidPlatformException;
 import com.google.devtools.build.lib.util.DetailedExitCode;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import com.google.devtools.build.skyframe.SkyFunction;

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredExecutionPlatformsValue.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/RegisteredExecutionPlatformsValue.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredExecutionPlatformsValue.java
similarity index 91%
rename from src/main/java/com/google/devtools/build/lib/skyframe/RegisteredExecutionPlatformsValue.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredExecutionPlatformsValue.java
index f8ee577..1246833 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/RegisteredExecutionPlatformsValue.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredExecutionPlatformsValue.java
@@ -12,10 +12,13 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import com.google.auto.value.AutoValue;
 import com.google.common.collect.ImmutableList;
+import com.google.devtools.build.lib.skyframe.BuildConfigurationKey;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.SkyFunctions;
 import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
 import com.google.devtools.build.skyframe.SkyFunctionName;
 import com.google.devtools.build.skyframe.SkyKey;

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsCycleReporter.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/RegisteredToolchainsCycleReporter.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsCycleReporter.java
similarity index 93%
rename from src/main/java/com/google/devtools/build/lib/skyframe/RegisteredToolchainsCycleReporter.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsCycleReporter.java
index c6af24c..53c44e5 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/RegisteredToolchainsCycleReporter.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsCycleReporter.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static java.util.stream.Collectors.joining;
 
@@ -25,7 +25,10 @@
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.events.Event;
 import com.google.devtools.build.lib.events.ExtendedEventHandler;
-import com.google.devtools.build.lib.skyframe.SingleToolchainResolutionValue.SingleToolchainResolutionKey;
+import com.google.devtools.build.lib.skyframe.AbstractLabelCycleReporter;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.SkyFunctions;
+import com.google.devtools.build.lib.skyframe.toolchains.SingleToolchainResolutionValue.SingleToolchainResolutionKey;
 import com.google.devtools.build.skyframe.CycleInfo;
 import com.google.devtools.build.skyframe.CyclesReporter;
 import com.google.devtools.build.skyframe.SkyKey;

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsFunction.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/RegisteredToolchainsFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsFunction.java
similarity index 95%
rename from src/main/java/com/google/devtools/build/lib/skyframe/RegisteredToolchainsFunction.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsFunction.java
index 81130b2..98bcbda 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/RegisteredToolchainsFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsFunction.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static com.google.common.collect.ImmutableList.toImmutableList;
 
@@ -38,6 +38,12 @@
 import com.google.devtools.build.lib.packages.semantics.BuildLanguageOptions;
 import com.google.devtools.build.lib.pkgcache.FilteringPolicies;
 import com.google.devtools.build.lib.server.FailureDetails.Toolchain.Code;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.ConfiguredValueCreationException;
+import com.google.devtools.build.lib.skyframe.PackageValue;
+import com.google.devtools.build.lib.skyframe.PrecomputedValue;
+import com.google.devtools.build.lib.skyframe.RepositoryMappingValue;
+import com.google.devtools.build.lib.skyframe.TargetPatternUtil;
 import com.google.devtools.build.lib.skyframe.TargetPatternUtil.InvalidTargetPatternException;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import com.google.devtools.build.skyframe.SkyFunction;

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsValue.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/RegisteredToolchainsValue.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsValue.java
similarity index 94%
rename from src/main/java/com/google/devtools/build/lib/skyframe/RegisteredToolchainsValue.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsValue.java
index 01fa349..d9139d7 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/RegisteredToolchainsValue.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsValue.java
@@ -12,11 +12,13 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import com.google.auto.value.AutoValue;
 import com.google.common.collect.ImmutableList;
 import com.google.devtools.build.lib.analysis.platform.DeclaredToolchainInfo;
+import com.google.devtools.build.lib.skyframe.BuildConfigurationKey;
+import com.google.devtools.build.lib.skyframe.SkyFunctions;
 import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
 import com.google.devtools.build.skyframe.SkyFunctionName;
 import com.google.devtools.build.skyframe.SkyKey;

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/SingleToolchainResolutionFunction.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SingleToolchainResolutionFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/SingleToolchainResolutionFunction.java
similarity index 96%
rename from src/main/java/com/google/devtools/build/lib/skyframe/SingleToolchainResolutionFunction.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/SingleToolchainResolutionFunction.java
index 59fc7e0..96de665 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SingleToolchainResolutionFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/SingleToolchainResolutionFunction.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static com.google.common.collect.ImmutableList.toImmutableList;
 import static java.util.stream.Collectors.joining;
@@ -32,9 +32,10 @@
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.events.Event;
 import com.google.devtools.build.lib.events.EventHandler;
-import com.google.devtools.build.lib.skyframe.PlatformLookupUtil.InvalidPlatformException;
-import com.google.devtools.build.lib.skyframe.RegisteredToolchainsFunction.InvalidToolchainLabelException;
-import com.google.devtools.build.lib.skyframe.SingleToolchainResolutionValue.SingleToolchainResolutionKey;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.toolchains.PlatformLookupUtil.InvalidPlatformException;
+import com.google.devtools.build.lib.skyframe.toolchains.RegisteredToolchainsFunction.InvalidToolchainLabelException;
+import com.google.devtools.build.lib.skyframe.toolchains.SingleToolchainResolutionValue.SingleToolchainResolutionKey;
 import com.google.devtools.build.skyframe.SkyFunction;
 import com.google.devtools.build.skyframe.SkyFunctionException;
 import com.google.devtools.build.skyframe.SkyKey;

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/SingleToolchainResolutionValue.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/SingleToolchainResolutionValue.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/SingleToolchainResolutionValue.java
similarity index 94%
rename from src/main/java/com/google/devtools/build/lib/skyframe/SingleToolchainResolutionValue.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/SingleToolchainResolutionValue.java
index a9718ed..9c1cba2 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/SingleToolchainResolutionValue.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/SingleToolchainResolutionValue.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import com.google.auto.value.AutoValue;
 import com.google.common.annotations.VisibleForTesting;
@@ -21,6 +21,9 @@
 import com.google.devtools.build.lib.analysis.config.ToolchainTypeRequirement;
 import com.google.devtools.build.lib.analysis.platform.ToolchainTypeInfo;
 import com.google.devtools.build.lib.cmdline.Label;
+import com.google.devtools.build.lib.skyframe.BuildConfigurationKey;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.SkyFunctions;
 import com.google.devtools.build.skyframe.SkyFunctionName;
 import com.google.devtools.build.skyframe.SkyKey;
 import com.google.devtools.build.skyframe.SkyValue;

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainContextKey.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ToolchainContextKey.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainContextKey.java
similarity index 93%
rename from src/main/java/com/google/devtools/build/lib/skyframe/ToolchainContextKey.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainContextKey.java
index c9551c9..416c421 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/ToolchainContextKey.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainContextKey.java
@@ -11,13 +11,14 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-package com.google.devtools.build.lib.skyframe;
-
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import com.google.auto.value.AutoValue;
 import com.google.common.collect.ImmutableSet;
 import com.google.devtools.build.lib.analysis.config.ToolchainTypeRequirement;
 import com.google.devtools.build.lib.cmdline.Label;
+import com.google.devtools.build.lib.skyframe.BuildConfigurationKey;
+import com.google.devtools.build.lib.skyframe.SkyFunctions;
 import com.google.devtools.build.skyframe.SkyFunctionName;
 import com.google.devtools.build.skyframe.SkyKey;
 import java.util.Optional;

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainException.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ToolchainException.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainException.java
similarity index 90%
rename from src/main/java/com/google/devtools/build/lib/skyframe/ToolchainException.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainException.java
index 20724b4..f121231 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/ToolchainException.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainException.java
@@ -11,13 +11,15 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import com.google.common.base.Strings;
 import com.google.devtools.build.lib.analysis.TargetAndConfiguration;
 import com.google.devtools.build.lib.server.FailureDetails;
 import com.google.devtools.build.lib.server.FailureDetails.FailureDetail;
 import com.google.devtools.build.lib.server.FailureDetails.Toolchain.Code;
+import com.google.devtools.build.lib.skyframe.ConfiguredValueCreationException;
+import com.google.devtools.build.lib.skyframe.DetailedException;
 import com.google.devtools.build.lib.util.DetailedExitCode;
 
 /** Base class for exceptions that happen during toolchain resolution. */
@@ -56,7 +58,7 @@
    *
    * <p>If one cannot be found, make a new one.
    */
-  ConfiguredValueCreationException asConfiguredValueCreationException(
+  public ConfiguredValueCreationException asConfiguredValueCreationException(
       TargetAndConfiguration targetAndConfiguration) {
     for (Throwable cause = getCause();
         cause != null && cause != cause.getCause();

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainResolutionFunction.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ToolchainResolutionFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainResolutionFunction.java
similarity index 95%
rename from src/main/java/com/google/devtools/build/lib/skyframe/ToolchainResolutionFunction.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainResolutionFunction.java
index 83c6a8a..99def70 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/ToolchainResolutionFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainResolutionFunction.java
@@ -11,7 +11,7 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.common.collect.ImmutableSet.toImmutableSet;
@@ -34,12 +34,14 @@
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.events.Event;
 import com.google.devtools.build.lib.server.FailureDetails.Toolchain.Code;
-import com.google.devtools.build.lib.skyframe.ConstraintValueLookupUtil.InvalidConstraintValueException;
-import com.google.devtools.build.lib.skyframe.PlatformLookupUtil.InvalidPlatformException;
-import com.google.devtools.build.lib.skyframe.RegisteredExecutionPlatformsFunction.InvalidExecutionPlatformLabelException;
-import com.google.devtools.build.lib.skyframe.RegisteredToolchainsFunction.InvalidToolchainLabelException;
-import com.google.devtools.build.lib.skyframe.SingleToolchainResolutionValue.SingleToolchainResolutionKey;
-import com.google.devtools.build.lib.skyframe.ToolchainTypeLookupUtil.InvalidToolchainTypeException;
+import com.google.devtools.build.lib.skyframe.BuildConfigurationKey;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.toolchains.ConstraintValueLookupUtil.InvalidConstraintValueException;
+import com.google.devtools.build.lib.skyframe.toolchains.PlatformLookupUtil.InvalidPlatformException;
+import com.google.devtools.build.lib.skyframe.toolchains.RegisteredExecutionPlatformsFunction.InvalidExecutionPlatformLabelException;
+import com.google.devtools.build.lib.skyframe.toolchains.RegisteredToolchainsFunction.InvalidToolchainLabelException;
+import com.google.devtools.build.lib.skyframe.toolchains.SingleToolchainResolutionValue.SingleToolchainResolutionKey;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainTypeLookupUtil.InvalidToolchainTypeException;
 import com.google.devtools.build.skyframe.SkyFunction;
 import com.google.devtools.build.skyframe.SkyFunctionException;
 import com.google.devtools.build.skyframe.SkyKey;
@@ -283,8 +285,9 @@
             .build();
 
     // Load the host and target platforms early, to check for errors.
-    PlatformLookupUtil.getPlatformInfo(
-        ImmutableList.of(hostPlatformKey, targetPlatformKey), environment);
+    var unused =
+        PlatformLookupUtil.getPlatformInfo(
+            ImmutableList.of(hostPlatformKey, targetPlatformKey), environment);
     if (environment.valuesMissing()) {
       throw new ValueMissingException();
     }

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainTypeLookupUtil.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/ToolchainTypeLookupUtil.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainTypeLookupUtil.java
similarity index 96%
rename from src/main/java/com/google/devtools/build/lib/skyframe/ToolchainTypeLookupUtil.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainTypeLookupUtil.java
index c9f5846..2d18b84 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/ToolchainTypeLookupUtil.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainTypeLookupUtil.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Iterables;
@@ -24,6 +24,8 @@
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.packages.NoSuchThingException;
 import com.google.devtools.build.lib.server.FailureDetails.Toolchain.Code;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.ConfiguredValueCreationException;
 import com.google.devtools.build.skyframe.SkyFunction.Environment;
 import com.google.devtools.build.skyframe.SkyframeLookupResult;
 import java.util.HashMap;

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/UnloadedToolchainContext.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/UnloadedToolchainContext.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/UnloadedToolchainContext.java
similarity index 96%
rename from src/main/java/com/google/devtools/build/lib/skyframe/UnloadedToolchainContext.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/UnloadedToolchainContext.java
index 6b915a4..bec755a 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/UnloadedToolchainContext.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/UnloadedToolchainContext.java
@@ -11,7 +11,7 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;

src/main/java/com/google/devtools/build/lib/skyframe/toolchains/UnloadedToolchainContextImpl.java

diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/UnloadedToolchainContextImpl.java b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/UnloadedToolchainContextImpl.java
similarity index 98%
rename from src/main/java/com/google/devtools/build/lib/skyframe/UnloadedToolchainContextImpl.java
rename to src/main/java/com/google/devtools/build/lib/skyframe/toolchains/UnloadedToolchainContextImpl.java
index 9124e033f..6ec4245 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/UnloadedToolchainContextImpl.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/toolchains/UnloadedToolchainContextImpl.java
@@ -11,7 +11,7 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import com.google.auto.value.AutoValue;
 import com.google.common.collect.ImmutableMap;

src/test/java/com/google/devtools/build/lib/analysis/BUILD

diff --git a/src/test/java/com/google/devtools/build/lib/analysis/BUILD b/src/test/java/com/google/devtools/build/lib/analysis/BUILD
index 932b361..4b5a805 100644
--- a/src/test/java/com/google/devtools/build/lib/analysis/BUILD
+++ b/src/test/java/com/google/devtools/build/lib/analysis/BUILD
@@ -151,14 +151,14 @@
         "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
         "//src/main/java/com/google/devtools/build/lib/skyframe:precomputed_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe:skyframe_cluster",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:toolchain_context_key",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:toolchain_exception",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:unloaded_toolchain_context",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:unloaded_toolchain_context_impl",
         "//src/main/java/com/google/devtools/build/lib/skyframe:workspace_status_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/testutils",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/testutils:depsutils",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_context_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:unloaded_toolchain_context",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:unloaded_toolchain_context_impl",
         "//src/main/java/com/google/devtools/build/lib/util",
         "//src/main/java/com/google/devtools/build/lib/util:detailed_exit_code",
         "//src/main/java/com/google/devtools/build/lib/util:filetype",

src/test/java/com/google/devtools/build/lib/analysis/ResolvedToolchainContextTest.java

diff --git a/src/test/java/com/google/devtools/build/lib/analysis/ResolvedToolchainContextTest.java b/src/test/java/com/google/devtools/build/lib/analysis/ResolvedToolchainContextTest.java
index 0b2d062..bbaa6c2 100644
--- a/src/test/java/com/google/devtools/build/lib/analysis/ResolvedToolchainContextTest.java
+++ b/src/test/java/com/google/devtools/build/lib/analysis/ResolvedToolchainContextTest.java
@@ -26,10 +26,10 @@
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.rules.platform.ToolchainTestCase;
 import com.google.devtools.build.lib.skyframe.ConfiguredTargetAndData;
-import com.google.devtools.build.lib.skyframe.ToolchainContextKey;
-import com.google.devtools.build.lib.skyframe.ToolchainException;
-import com.google.devtools.build.lib.skyframe.UnloadedToolchainContext;
-import com.google.devtools.build.lib.skyframe.UnloadedToolchainContextImpl;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainContextKey;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainException;
+import com.google.devtools.build.lib.skyframe.toolchains.UnloadedToolchainContext;
+import com.google.devtools.build.lib.skyframe.toolchains.UnloadedToolchainContextImpl;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;

src/test/java/com/google/devtools/build/lib/analysis/util/BUILD

diff --git a/src/test/java/com/google/devtools/build/lib/analysis/util/BUILD b/src/test/java/com/google/devtools/build/lib/analysis/util/BUILD
index 7e9268c..d7c0d49 100644
--- a/src/test/java/com/google/devtools/build/lib/analysis/util/BUILD
+++ b/src/test/java/com/google/devtools/build/lib/analysis/util/BUILD
@@ -121,10 +121,10 @@
         "//src/main/java/com/google/devtools/build/lib/skyframe:skyframe_executor_repository_helpers_holder",
         "//src/main/java/com/google/devtools/build/lib/skyframe:starlark_builtins_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe:target_pattern_phase_value",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:toolchain_exception",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:unloaded_toolchain_context",
         "//src/main/java/com/google/devtools/build/lib/skyframe:workspace_info",
         "//src/main/java/com/google/devtools/build/lib/skyframe/packages:PackageFactoryBuilderWithSkyframeForTesting",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:unloaded_toolchain_context",
         "//src/main/java/com/google/devtools/build/lib/util",
         "//src/main/java/com/google/devtools/build/lib/util:abrupt_exit_exception",
         "//src/main/java/com/google/devtools/build/lib/util:crash_failure_details",

src/test/java/com/google/devtools/build/lib/analysis/util/BuildViewForTesting.java

diff --git a/src/test/java/com/google/devtools/build/lib/analysis/util/BuildViewForTesting.java b/src/test/java/com/google/devtools/build/lib/analysis/util/BuildViewForTesting.java
index ea1c2e7..d1b2ef0 100644
--- a/src/test/java/com/google/devtools/build/lib/analysis/util/BuildViewForTesting.java
+++ b/src/test/java/com/google/devtools/build/lib/analysis/util/BuildViewForTesting.java
@@ -114,8 +114,8 @@
 import com.google.devtools.build.lib.skyframe.SkyframeExecutorWrappingWalkableGraph;
 import com.google.devtools.build.lib.skyframe.StarlarkBuiltinsValue;
 import com.google.devtools.build.lib.skyframe.TargetPatternPhaseValue;
-import com.google.devtools.build.lib.skyframe.ToolchainException;
-import com.google.devtools.build.lib.skyframe.UnloadedToolchainContext;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainException;
+import com.google.devtools.build.lib.skyframe.toolchains.UnloadedToolchainContext;
 import com.google.devtools.build.lib.util.AbruptExitException;
 import com.google.devtools.build.lib.util.OrderedSetMultimap;
 import com.google.devtools.build.skyframe.NodeEntry;

src/test/java/com/google/devtools/build/lib/repository/BUILD

diff --git a/src/test/java/com/google/devtools/build/lib/repository/BUILD b/src/test/java/com/google/devtools/build/lib/repository/BUILD
index b7b5c05..a44de9a 100644
--- a/src/test/java/com/google/devtools/build/lib/repository/BUILD
+++ b/src/test/java/com/google/devtools/build/lib/repository/BUILD
@@ -33,6 +33,8 @@
         "//src/main/java/com/google/devtools/build/lib/skyframe:precomputed_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe:sky_functions",
         "//src/main/java/com/google/devtools/build/lib/skyframe:skyframe_cluster",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:registered_execution_platforms_function",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:registered_toolchains_function",
         "//src/main/java/com/google/devtools/build/lib/util/io",
         "//src/main/java/com/google/devtools/build/lib/vfs",
         "//src/main/java/com/google/devtools/build/skyframe",

src/test/java/com/google/devtools/build/lib/repository/ExternalPackageHelperTest.java

diff --git a/src/test/java/com/google/devtools/build/lib/repository/ExternalPackageHelperTest.java b/src/test/java/com/google/devtools/build/lib/repository/ExternalPackageHelperTest.java
index 17f643d..8f1ee41 100644
--- a/src/test/java/com/google/devtools/build/lib/repository/ExternalPackageHelperTest.java
+++ b/src/test/java/com/google/devtools/build/lib/repository/ExternalPackageHelperTest.java
@@ -52,11 +52,11 @@
 import com.google.devtools.build.lib.skyframe.PackageLookupFunction;
 import com.google.devtools.build.lib.skyframe.PackageLookupFunction.CrossRepositoryLabelViolationStrategy;
 import com.google.devtools.build.lib.skyframe.PrecomputedValue;
-import com.google.devtools.build.lib.skyframe.RegisteredExecutionPlatformsFunction;
-import com.google.devtools.build.lib.skyframe.RegisteredToolchainsFunction;
 import com.google.devtools.build.lib.skyframe.SkyFunctions;
 import com.google.devtools.build.lib.skyframe.SkyframeExecutor;
 import com.google.devtools.build.lib.skyframe.WorkspaceFileFunction;
+import com.google.devtools.build.lib.skyframe.toolchains.RegisteredExecutionPlatformsFunction;
+import com.google.devtools.build.lib.skyframe.toolchains.RegisteredToolchainsFunction;
 import com.google.devtools.build.lib.util.io.TimestampGranularityMonitor;
 import com.google.devtools.build.lib.vfs.FileStateKey;
 import com.google.devtools.build.lib.vfs.Path;

src/test/java/com/google/devtools/build/lib/rules/platform/BUILD

diff --git a/src/test/java/com/google/devtools/build/lib/rules/platform/BUILD b/src/test/java/com/google/devtools/build/lib/rules/platform/BUILD
index 6f2f949..88cdeea 100644
--- a/src/test/java/com/google/devtools/build/lib/rules/platform/BUILD
+++ b/src/test/java/com/google/devtools/build/lib/rules/platform/BUILD
@@ -44,7 +44,7 @@
         "//src/main/java/com/google/devtools/build/lib/analysis:config/toolchain_type_requirement",
         "//src/main/java/com/google/devtools/build/lib/analysis/platform",
         "//src/main/java/com/google/devtools/build/lib/cmdline",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:skyframe_cluster",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:registered_toolchains_value",
         "//src/main/java/com/google/devtools/build/skyframe",
         "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
         "//src/test/java/com/google/devtools/build/lib/analysis/util",

src/test/java/com/google/devtools/build/lib/rules/platform/ToolchainTestCase.java

diff --git a/src/test/java/com/google/devtools/build/lib/rules/platform/ToolchainTestCase.java b/src/test/java/com/google/devtools/build/lib/rules/platform/ToolchainTestCase.java
index 966a6d7..78e06b2 100644
--- a/src/test/java/com/google/devtools/build/lib/rules/platform/ToolchainTestCase.java
+++ b/src/test/java/com/google/devtools/build/lib/rules/platform/ToolchainTestCase.java
@@ -28,7 +28,7 @@
 import com.google.devtools.build.lib.analysis.util.BuildViewTestCase;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.cmdline.PackageIdentifier;
-import com.google.devtools.build.lib.skyframe.RegisteredToolchainsValue;
+import com.google.devtools.build.lib.skyframe.toolchains.RegisteredToolchainsValue;
 import com.google.devtools.build.lib.skyframe.util.SkyframeExecutorTestUtils;
 import com.google.devtools.build.skyframe.EvaluationResult;
 import com.google.devtools.build.skyframe.SkyKey;

src/test/java/com/google/devtools/build/lib/skyframe/BUILD

diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/BUILD b/src/test/java/com/google/devtools/build/lib/skyframe/BUILD
index c46ff90..ecca373 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/BUILD
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/BUILD
@@ -8,7 +8,10 @@
 filegroup(
     name = "srcs",
     testonly = 0,
-    srcs = glob(["**"]) + ["//src/test/java/com/google/devtools/build/lib/skyframe/rewinding:srcs"],
+    srcs = glob(["**"]) + [
+        "//src/test/java/com/google/devtools/build/lib/skyframe/rewinding:srcs",
+        "//src/test/java/com/google/devtools/build/lib/skyframe/toolchains:srcs",
+    ],
     visibility = ["//src/test/java/com/google/devtools/build/lib:__pkg__"],
 )
 
@@ -226,14 +229,12 @@
         "//src/main/java/com/google/devtools/build/lib/skyframe:incremental_artifact_conflict_finder",
         "//src/main/java/com/google/devtools/build/lib/skyframe:local_repository_lookup_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe:metadata_consumer_for_metrics",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:no_matching_platform_data",
         "//src/main/java/com/google/devtools/build/lib/skyframe:output_store",
         "//src/main/java/com/google/devtools/build/lib/skyframe:package_error_message_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe:package_lookup_function",
         "//src/main/java/com/google/devtools/build/lib/skyframe:package_lookup_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe:package_progress_receiver",
         "//src/main/java/com/google/devtools/build/lib/skyframe:package_value",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:platform_lookup_util",
         "//src/main/java/com/google/devtools/build/lib/skyframe:precomputed_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe:prepare_deps_of_pattern_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe:prepare_deps_of_patterns_value",
@@ -253,16 +254,12 @@
         "//src/main/java/com/google/devtools/build/lib/skyframe:target_loading_util",
         "//src/main/java/com/google/devtools/build/lib/skyframe:target_pattern_phase_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe:tests_for_target_pattern_value",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:toolchain_context_key",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:toolchain_exception",
         "//src/main/java/com/google/devtools/build/lib/skyframe:top_level_status_events",
         "//src/main/java/com/google/devtools/build/lib/skyframe:transitive_base_traversal_function",
         "//src/main/java/com/google/devtools/build/lib/skyframe:transitive_target_key",
         "//src/main/java/com/google/devtools/build/lib/skyframe:transitive_traversal_function",
         "//src/main/java/com/google/devtools/build/lib/skyframe:transitive_traversal_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe:tree_artifact_value",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:unloaded_toolchain_context",
-        "//src/main/java/com/google/devtools/build/lib/skyframe:unloaded_toolchain_context_impl",
         "//src/main/java/com/google/devtools/build/lib/skyframe:workspace_info",
         "//src/main/java/com/google/devtools/build/lib/skyframe:workspace_name_value",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization",
@@ -270,6 +267,12 @@
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec:serialization-constant-annotation",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/testutils",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/testutils:depsutils",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:no_matching_platform_data",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:platform_lookup_util",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_context_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:unloaded_toolchain_context",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:unloaded_toolchain_context_impl",
         "//src/main/java/com/google/devtools/build/lib/testing/common:directory_listing_helper",
         "//src/main/java/com/google/devtools/build/lib/testing/common:fake-options",
         "//src/main/java/com/google/devtools/build/lib/util",

src/test/java/com/google/devtools/build/lib/skyframe/ConfigurationsForTargetsTest.java

diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/ConfigurationsForTargetsTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/ConfigurationsForTargetsTest.java
index 361ecdb..226dd97 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/ConfigurationsForTargetsTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/ConfigurationsForTargetsTest.java
@@ -43,6 +43,8 @@
 import com.google.devtools.build.lib.packages.Attribute;
 import com.google.devtools.build.lib.packages.RuleClassProvider;
 import com.google.devtools.build.lib.packages.Target;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainContextKey;
+import com.google.devtools.build.lib.skyframe.toolchains.UnloadedToolchainContextImpl;
 import com.google.devtools.build.lib.skyframe.util.SkyframeExecutorTestUtils;
 import com.google.devtools.build.lib.util.OrderedSetMultimap;
 import com.google.devtools.build.skyframe.AbstractSkyKey;

src/test/java/com/google/devtools/build/lib/skyframe/toolchains/BUILD

diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/BUILD b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/BUILD
new file mode 100644
index 0000000..2c10f66
--- /dev/null
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/BUILD
@@ -0,0 +1,213 @@
+load("@rules_java//java:defs.bzl", "java_test")
+
+package(
+    default_applicable_licenses = ["//:license"],
+    default_testonly = 1,
+    default_visibility = ["//src:__subpackages__"],
+)
+
+filegroup(
+    name = "srcs",
+    testonly = 0,
+    srcs = glob(["**"]),
+    visibility = ["//src:__subpackages__"],
+)
+
+java_test(
+    name = "ConstraintValueLookupUtilTest",
+    srcs = ["ConstraintValueLookupUtilTest.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/analysis:blaze_directories",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_value_creation_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:constraint_value_lookup_util",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//src/test/java/com/google/devtools/build/lib/analysis/util",
+        "//src/test/java/com/google/devtools/build/lib/rules/platform:testutil",
+        "//src/test/java/com/google/devtools/build/lib/skyframe:testutil",
+        "//src/test/java/com/google/devtools/build/skyframe:testutil",
+        "//third_party:auto_value",
+        "//third_party:guava",
+        "//third_party:jsr305",
+        "//third_party:junit4",
+        "//third_party:truth",
+    ],
+)
+
+java_test(
+    name = "PlatformLookupUtilTest",
+    srcs = ["PlatformLookupUtilTest.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/analysis:blaze_directories",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:platform_lookup_util",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//src/test/java/com/google/devtools/build/lib/analysis/util",
+        "//src/test/java/com/google/devtools/build/lib/rules/platform:testutil",
+        "//src/test/java/com/google/devtools/build/lib/skyframe:testutil",
+        "//src/test/java/com/google/devtools/build/skyframe:testutil",
+        "//third_party:auto_value",
+        "//third_party:guava",
+        "//third_party:jsr305",
+        "//third_party:junit4",
+        "//third_party:truth",
+    ],
+)
+
+java_test(
+    name = "RegisteredExecutionPlatformsFunctionTest",
+    srcs = ["RegisteredExecutionPlatformsFunctionTest.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/analysis:view_creation_failed_exception",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/bazel/bzlmod:resolution_impl",
+        "//src/main/java/com/google/devtools/build/lib/bazel/repository:repository_options",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:precomputed_value",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:platform_lookup_util",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:registered_execution_platforms_value",
+        "//src/main/java/com/google/devtools/build/lib/vfs",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//src/test/java/com/google/devtools/build/lib/bazel/bzlmod:util",
+        "//src/test/java/com/google/devtools/build/lib/rules/platform:testutil",
+        "//src/test/java/com/google/devtools/build/lib/skyframe:testutil",
+        "//src/test/java/com/google/devtools/build/skyframe:testutil",
+        "//third_party:guava",
+        "//third_party:guava-testlib",
+        "//third_party:jsr305",
+        "//third_party:junit4",
+        "//third_party:truth",
+    ],
+)
+
+java_test(
+    name = "RegisteredToolchainsFunctionTest",
+    srcs = ["RegisteredToolchainsFunctionTest.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/bazel/bzlmod:resolution_impl",
+        "//src/main/java/com/google/devtools/build/lib/bazel/repository:repository_options",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:precomputed_value",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:registered_toolchains_value",
+        "//src/main/java/com/google/devtools/build/lib/vfs",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//src/test/java/com/google/devtools/build/lib/bazel/bzlmod:util",
+        "//src/test/java/com/google/devtools/build/lib/rules/platform:testutil",
+        "//src/test/java/com/google/devtools/build/skyframe:testutil",
+        "//third_party:guava",
+        "//third_party:guava-testlib",
+        "//third_party:junit4",
+        "//third_party:truth",
+    ],
+)
+
+java_test(
+    name = "SingleToolchainResolutionFunctionTest",
+    srcs = ["SingleToolchainResolutionFunctionTest.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:single_toolchain_resolution_value",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//src/test/java/com/google/devtools/build/lib/rules/platform:testutil",
+        "//src/test/java/com/google/devtools/build/lib/skyframe:testutil",
+        "//src/test/java/com/google/devtools/build/skyframe:testutil",
+        "//third_party:guava",
+        "//third_party:guava-testlib",
+        "//third_party:junit4",
+        "//third_party:truth",
+    ],
+)
+
+java_test(
+    name = "ToolchainResolutionFunctionTest",
+    srcs = ["ToolchainResolutionFunctionTest.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/analysis:config/toolchain_type_requirement",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:constraint_value_lookup_util",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:platform_lookup_util",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_context_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_type_lookup_util",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:unloaded_toolchain_context",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//src/test/java/com/google/devtools/build/lib/analysis/testing",
+        "//src/test/java/com/google/devtools/build/lib/rules/platform:testutil",
+        "//src/test/java/com/google/devtools/build/lib/skyframe:testutil",
+        "//src/test/java/com/google/devtools/build/skyframe:testutil",
+        "//third_party:guava",
+        "//third_party:junit4",
+        "//third_party:truth",
+    ],
+)
+
+java_test(
+    name = "ToolchainsForTargetsTest",
+    srcs = ["ToolchainsForTargetsTest.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/actions",
+        "//src/main/java/com/google/devtools/build/lib/analysis:analysis_cluster",
+        "//src/main/java/com/google/devtools/build/lib/analysis:blaze_directories",
+        "//src/main/java/com/google/devtools/build/lib/analysis:configured_target",
+        "//src/main/java/com/google/devtools/build/lib/analysis:constraints/incompatible_target_checker",
+        "//src/main/java/com/google/devtools/build/lib/analysis:target_and_configuration",
+        "//src/main/java/com/google/devtools/build/lib/analysis:toolchain_collection",
+        "//src/main/java/com/google/devtools/build/lib/analysis:toolchain_context",
+        "//src/main/java/com/google/devtools/build/lib/analysis/producers",
+        "//src/main/java/com/google/devtools/build/lib/causes",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/collect/nestedset",
+        "//src/main/java/com/google/devtools/build/lib/packages",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_value_creation_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:skyframe_cluster",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:unloaded_toolchain_context",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//src/test/java/com/google/devtools/build/lib/analysis/testing",
+        "//src/test/java/com/google/devtools/build/lib/analysis/util",
+        "//src/test/java/com/google/devtools/build/lib/skyframe:testutil",
+        "//third_party:auto_value",
+        "//third_party:error_prone_annotations",
+        "//third_party:guava",
+        "//third_party:junit4",
+        "//third_party:truth",
+    ],
+)
+
+java_test(
+    name = "ToolchainTypeLookupUtilTest",
+    srcs = ["ToolchainTypeLookupUtilTest.java"],
+    deps = [
+        "//src/main/java/com/google/devtools/build/lib/analysis:blaze_directories",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
+        "//src/main/java/com/google/devtools/build/lib/cmdline",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_target_key",
+        "//src/main/java/com/google/devtools/build/lib/skyframe:configured_value_creation_exception",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/toolchains:toolchain_type_lookup_util",
+        "//src/main/java/com/google/devtools/build/skyframe",
+        "//src/main/java/com/google/devtools/build/skyframe:skyframe-objects",
+        "//src/test/java/com/google/devtools/build/lib/analysis/util",
+        "//src/test/java/com/google/devtools/build/lib/rules/platform:testutil",
+        "//src/test/java/com/google/devtools/build/lib/skyframe:testutil",
+        "//src/test/java/com/google/devtools/build/skyframe:testutil",
+        "//third_party:auto_value",
+        "//third_party:guava",
+        "//third_party:jsr305",
+        "//third_party:junit4",
+        "//third_party:truth",
+    ],
+)

src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ConstraintValueLookupUtilTest.java

diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/ConstraintValueLookupUtilTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ConstraintValueLookupUtilTest.java
similarity index 96%
rename from src/test/java/com/google/devtools/build/lib/skyframe/ConstraintValueLookupUtilTest.java
rename to src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ConstraintValueLookupUtilTest.java
index cff691b..d769184 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/ConstraintValueLookupUtilTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ConstraintValueLookupUtilTest.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static com.google.common.truth.Truth.assertThat;
 import static com.google.devtools.build.skyframe.EvaluationResultSubjectFactory.assertThatEvaluationResult;
@@ -25,7 +25,9 @@
 import com.google.devtools.build.lib.analysis.util.AnalysisMock;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.rules.platform.ToolchainTestCase;
-import com.google.devtools.build.lib.skyframe.ConstraintValueLookupUtil.InvalidConstraintValueException;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.ConfiguredValueCreationException;
+import com.google.devtools.build.lib.skyframe.toolchains.ConstraintValueLookupUtil.InvalidConstraintValueException;
 import com.google.devtools.build.lib.skyframe.util.SkyframeExecutorTestUtils;
 import com.google.devtools.build.skyframe.EvaluationResult;
 import com.google.devtools.build.skyframe.SkyFunction;

src/test/java/com/google/devtools/build/lib/skyframe/toolchains/PlatformLookupUtilTest.java

diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/PlatformLookupUtilTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/PlatformLookupUtilTest.java
similarity index 96%
rename from src/test/java/com/google/devtools/build/lib/skyframe/PlatformLookupUtilTest.java
rename to src/test/java/com/google/devtools/build/lib/skyframe/toolchains/PlatformLookupUtilTest.java
index 38154d1..0724c91 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/PlatformLookupUtilTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/PlatformLookupUtilTest.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static com.google.common.truth.Truth.assertThat;
 import static com.google.devtools.build.skyframe.EvaluationResultSubjectFactory.assertThatEvaluationResult;
@@ -25,7 +25,8 @@
 import com.google.devtools.build.lib.analysis.util.AnalysisMock;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.rules.platform.ToolchainTestCase;
-import com.google.devtools.build.lib.skyframe.PlatformLookupUtil.InvalidPlatformException;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.toolchains.PlatformLookupUtil.InvalidPlatformException;
 import com.google.devtools.build.lib.skyframe.util.SkyframeExecutorTestUtils;
 import com.google.devtools.build.skyframe.EvaluationResult;
 import com.google.devtools.build.skyframe.SkyFunction;

src/test/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredExecutionPlatformsFunctionTest.java

diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/RegisteredExecutionPlatformsFunctionTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredExecutionPlatformsFunctionTest.java
similarity index 98%
rename from src/test/java/com/google/devtools/build/lib/skyframe/RegisteredExecutionPlatformsFunctionTest.java
rename to src/test/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredExecutionPlatformsFunctionTest.java
index f40c8d0..162eb7c 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/RegisteredExecutionPlatformsFunctionTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredExecutionPlatformsFunctionTest.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static com.google.common.truth.Truth.assertThat;
 import static com.google.devtools.build.lib.bazel.bzlmod.BzlmodTestUtil.createModuleKey;
@@ -35,8 +35,10 @@
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.cmdline.PackageIdentifier;
 import com.google.devtools.build.lib.rules.platform.ToolchainTestCase;
-import com.google.devtools.build.lib.skyframe.PlatformLookupUtil.InvalidPlatformException;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.PrecomputedValue;
 import com.google.devtools.build.lib.skyframe.PrecomputedValue.Injected;
+import com.google.devtools.build.lib.skyframe.toolchains.PlatformLookupUtil.InvalidPlatformException;
 import com.google.devtools.build.lib.skyframe.util.SkyframeExecutorTestUtils;
 import com.google.devtools.build.lib.vfs.Path;
 import com.google.devtools.build.skyframe.EvaluationResult;

src/test/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsFunctionTest.java

diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/RegisteredToolchainsFunctionTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsFunctionTest.java
similarity index 99%
rename from src/test/java/com/google/devtools/build/lib/skyframe/RegisteredToolchainsFunctionTest.java
rename to src/test/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsFunctionTest.java
index d9bce3c..49b331c 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/RegisteredToolchainsFunctionTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/RegisteredToolchainsFunctionTest.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static com.google.common.truth.Truth.assertThat;
 import static com.google.devtools.build.lib.bazel.bzlmod.BzlmodTestUtil.createModuleKey;
@@ -33,6 +33,7 @@
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.cmdline.PackageIdentifier;
 import com.google.devtools.build.lib.rules.platform.ToolchainTestCase;
+import com.google.devtools.build.lib.skyframe.PrecomputedValue;
 import com.google.devtools.build.lib.skyframe.PrecomputedValue.Injected;
 import com.google.devtools.build.lib.vfs.Path;
 import com.google.devtools.build.skyframe.EvaluationResult;

src/test/java/com/google/devtools/build/lib/skyframe/toolchains/SingleToolchainResolutionFunctionTest.java

diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/SingleToolchainResolutionFunctionTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/SingleToolchainResolutionFunctionTest.java
similarity index 97%
rename from src/test/java/com/google/devtools/build/lib/skyframe/SingleToolchainResolutionFunctionTest.java
rename to src/test/java/com/google/devtools/build/lib/skyframe/toolchains/SingleToolchainResolutionFunctionTest.java
index 23f4318..a02df36 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/SingleToolchainResolutionFunctionTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/SingleToolchainResolutionFunctionTest.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static com.google.common.truth.Truth.assertThat;
 import static com.google.devtools.build.skyframe.EvaluationResultSubjectFactory.assertThatEvaluationResult;
@@ -22,6 +22,7 @@
 import com.google.common.testing.EqualsTester;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.rules.platform.ToolchainTestCase;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
 import com.google.devtools.build.lib.skyframe.util.SkyframeExecutorTestUtils;
 import com.google.devtools.build.skyframe.EvaluationResult;
 import com.google.devtools.build.skyframe.SkyKey;

src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainResolutionFunctionTest.java

diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/ToolchainResolutionFunctionTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainResolutionFunctionTest.java
similarity index 97%
rename from src/test/java/com/google/devtools/build/lib/skyframe/ToolchainResolutionFunctionTest.java
rename to src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainResolutionFunctionTest.java
index f333cf6..bc36bd0 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/ToolchainResolutionFunctionTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainResolutionFunctionTest.java
@@ -11,7 +11,7 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static com.google.common.truth.Truth.assertThat;
 import static com.google.devtools.build.lib.analysis.testing.ToolchainContextSubject.assertThat;
@@ -19,12 +19,11 @@
 
 import com.google.common.collect.ImmutableList;
 import com.google.devtools.build.lib.analysis.config.ToolchainTypeRequirement;
-import com.google.devtools.build.lib.analysis.platform.ToolchainTypeInfo;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.rules.platform.ToolchainTestCase;
-import com.google.devtools.build.lib.skyframe.ConstraintValueLookupUtil.InvalidConstraintValueException;
-import com.google.devtools.build.lib.skyframe.PlatformLookupUtil.InvalidPlatformException;
-import com.google.devtools.build.lib.skyframe.ToolchainTypeLookupUtil.InvalidToolchainTypeException;
+import com.google.devtools.build.lib.skyframe.toolchains.ConstraintValueLookupUtil.InvalidConstraintValueException;
+import com.google.devtools.build.lib.skyframe.toolchains.PlatformLookupUtil.InvalidPlatformException;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainTypeLookupUtil.InvalidToolchainTypeException;
 import com.google.devtools.build.lib.skyframe.util.SkyframeExecutorTestUtils;
 import com.google.devtools.build.skyframe.EvaluationResult;
 import com.google.devtools.build.skyframe.SkyKey;
@@ -234,7 +233,6 @@
     Label secondToolchainTypeLabel = Label.parseCanonicalUnchecked("//second:toolchain_type");
     ToolchainTypeRequirement secondToolchainTypeRequirement =
         ToolchainTypeRequirement.create(secondToolchainTypeLabel);
-    ToolchainTypeInfo secondToolchainTypeInfo = ToolchainTypeInfo.create(secondToolchainTypeLabel);
     scratch.file("second/BUILD", "toolchain_type(name = 'toolchain_type')");
 
     addToolchain(
@@ -298,7 +296,6 @@
     Label secondToolchainTypeLabel = Label.parseCanonicalUnchecked("//second:toolchain_type");
     ToolchainTypeRequirement secondToolchainTypeRequirement =
         ToolchainTypeRequirement.builder(secondToolchainTypeLabel).mandatory(false).build();
-    ToolchainTypeInfo secondToolchainTypeInfo = ToolchainTypeInfo.create(secondToolchainTypeLabel);
     scratch.file("second/BUILD", "toolchain_type(name = 'toolchain_type')");
 
     addToolchain(
@@ -343,7 +340,6 @@
     Label secondToolchainTypeLabel = Label.parseCanonicalUnchecked("//second:toolchain_type");
     ToolchainTypeRequirement secondToolchainTypeRequirement =
         ToolchainTypeRequirement.builder(secondToolchainTypeLabel).mandatory(false).build();
-    ToolchainTypeInfo secondToolchainTypeInfo = ToolchainTypeInfo.create(secondToolchainTypeLabel);
     scratch.file("second/BUILD", "toolchain_type(name = 'toolchain_type')");
 
     addToolchain(

src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainTypeLookupUtilTest.java

diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/ToolchainTypeLookupUtilTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainTypeLookupUtilTest.java
similarity index 96%
rename from src/test/java/com/google/devtools/build/lib/skyframe/ToolchainTypeLookupUtilTest.java
rename to src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainTypeLookupUtilTest.java
index 2580717..7862d88 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/ToolchainTypeLookupUtilTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainTypeLookupUtilTest.java
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static com.google.common.truth.Truth.assertThat;
 import static com.google.devtools.build.skyframe.EvaluationResultSubjectFactory.assertThatEvaluationResult;
@@ -25,7 +25,9 @@
 import com.google.devtools.build.lib.analysis.util.AnalysisMock;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.rules.platform.ToolchainTestCase;
-import com.google.devtools.build.lib.skyframe.ToolchainTypeLookupUtil.InvalidToolchainTypeException;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.ConfiguredValueCreationException;
+import com.google.devtools.build.lib.skyframe.toolchains.ToolchainTypeLookupUtil.InvalidToolchainTypeException;
 import com.google.devtools.build.lib.skyframe.util.SkyframeExecutorTestUtils;
 import com.google.devtools.build.skyframe.EvaluationResult;
 import com.google.devtools.build.skyframe.SkyFunction;

src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainsForTargetsTest.java

diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/ToolchainsForTargetsTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainsForTargetsTest.java
similarity index 98%
rename from src/test/java/com/google/devtools/build/lib/skyframe/ToolchainsForTargetsTest.java
rename to src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainsForTargetsTest.java
index b06b974..0304616 100644
--- a/src/test/java/com/google/devtools/build/lib/skyframe/ToolchainsForTargetsTest.java
+++ b/src/test/java/com/google/devtools/build/lib/skyframe/toolchains/ToolchainsForTargetsTest.java
@@ -11,7 +11,7 @@
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.
-package com.google.devtools.build.lib.skyframe;
+package com.google.devtools.build.lib.skyframe.toolchains;
 
 import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.common.truth.Truth.assertThat;
@@ -44,6 +44,10 @@
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.packages.RuleClassProvider;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetFunction;
+import com.google.devtools.build.lib.skyframe.ConfiguredTargetKey;
+import com.google.devtools.build.lib.skyframe.ConfiguredValueCreationException;
+import com.google.devtools.build.lib.skyframe.PrerequisiteProducer;
 import com.google.devtools.build.lib.skyframe.util.SkyframeExecutorTestUtils;
 import com.google.devtools.build.skyframe.EvaluationResult;
 import com.google.devtools.build.skyframe.SkyFunction;
@@ -96,7 +100,7 @@
   }
 
   /**
-   * Returns a {@link ToolchainCollection<UnloadedToolchainContext>} as the result of {@link
+   * Returns a {@link ToolchainCollection< UnloadedToolchainContext >} as the result of {@link
    * PrerequisiteProducer#getDependencyContext}.
    */
   @AutoValue