diff --git a/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/Activator.java b/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/Activator.java
index a7ff2ad..ac29c6b 100644
--- a/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/Activator.java
+++ b/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/Activator.java
@@ -61,7 +61,7 @@
   public void start(BundleContext context) throws Exception {
     plugin = this;
     super.start(context);
-    this.command = new BazelCommand();
+    this.command = new BazelCommand(new BazelAspectLocationImpl(), new CommandConsoleFactoryImpl());
     // Get the bazel path from the settings
     this.command.setBazelPath(getPreferenceStore().getString("BAZEL_PATH"));
     getPreferenceStore().addPropertyChangeListener(new IPropertyChangeListener() {
diff --git a/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/command/BazelAspectLocationImpl.java b/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/BazelAspectLocationImpl.java
similarity index 93%
rename from com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/command/BazelAspectLocationImpl.java
rename to com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/BazelAspectLocationImpl.java
index 1503f1e..bbbf588 100644
--- a/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/command/BazelAspectLocationImpl.java
+++ b/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/BazelAspectLocationImpl.java
@@ -12,9 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.bazel.e4b.command;
+package com.google.devtools.bazel.e4b;
 
-import com.google.devtools.bazel.e4b.Activator;
+import com.google.devtools.bazel.e4b.command.BazelAspectLocation;
 import java.io.File;
 import java.io.IOException;
 import java.net.URL;
diff --git a/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/command/CommandConsoleFactoryImpl.java b/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/CommandConsoleFactoryImpl.java
similarity index 96%
rename from com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/command/CommandConsoleFactoryImpl.java
rename to com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/CommandConsoleFactoryImpl.java
index 2cf5485..ae94246 100644
--- a/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/command/CommandConsoleFactoryImpl.java
+++ b/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/CommandConsoleFactoryImpl.java
@@ -12,8 +12,9 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package com.google.devtools.bazel.e4b.command;
+package com.google.devtools.bazel.e4b;
 
+import com.google.devtools.bazel.e4b.command.CommandConsole;
 import com.google.devtools.bazel.e4b.command.CommandConsole.CommandConsoleFactory;
 import java.io.IOException;
 import java.io.OutputStream;
diff --git a/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/command/BazelCommand.java b/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/command/BazelCommand.java
index bffa541..162929e 100644
--- a/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/command/BazelCommand.java
+++ b/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/command/BazelCommand.java
@@ -17,6 +17,7 @@
 import com.google.common.base.Joiner;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
+import com.google.devtools.bazel.e4b.command.CommandConsole.CommandConsoleFactory;
 import java.io.File;
 import java.io.IOException;
 import java.io.OutputStream;
@@ -44,18 +45,29 @@
     NO_CONSOLE, SYSTEM, WORKSPACE
   }
 
-  // TODO: Inject
-  private static final BazelAspectLocation ASPECT_LOCATION = new BazelAspectLocationImpl();
-  private static final List<String> BUILD_OPTIONS =
-      ImmutableList.of("--watchfs", "--aspects=" + ASPECT_LOCATION.getAspectLabel());
-  private static final List<String> ASPECT_OPTIONS = ImmutableList
-      .<String>builder().addAll(BUILD_OPTIONS).add("-k",
-          "--output_groups=ide-info-text,ide-resolve,-_,-defaults", "--experimental_show_artifacts")
-      .build();
+  private final BazelAspectLocation aspectLocation;
+  private final CommandConsoleFactory consoleFactory;
+
+  private final List<String> buildOptions;
+  private final List<String> aspectOptions;
 
   private final Map<File, BazelInstance> instances = new HashMap<>();
   private String bazel = null;
 
+  /**
+   * Create a {@link BazelCommand} object, providing the implementation for locating aspect and
+   * getting console streams.
+   */
+  public BazelCommand(BazelAspectLocation aspectLocation, CommandConsoleFactory consoleFactory) {
+    this.aspectLocation = aspectLocation;
+    this.consoleFactory = consoleFactory;
+    this.buildOptions =
+        ImmutableList.of("--watchfs", "--aspects=" + aspectLocation.getAspectLabel());
+    this.aspectOptions = ImmutableList.<String>builder().addAll(buildOptions).add("-k",
+        "--output_groups=ide-info-text,ide-resolve,-_,-defaults", "--experimental_show_artifacts")
+        .build();
+  }
+
   private String getBazelPath() throws BazelNotFoundException {
     if (bazel == null) {
       throw new BazelNotFoundException.BazelNotSetException();
@@ -74,15 +86,14 @@
    * Check the version of Bazel: throws an exception if the version is incorrect or the path does
    * not point to a Bazel binary.
    */
-  public static void checkVersion(String bazel) throws BazelNotFoundException {
+  public void checkVersion(String bazel) throws BazelNotFoundException {
     File path = new File(bazel);
     if (!path.exists() || !path.canExecute()) {
       throw new BazelNotFoundException.BazelNotExecutableException();
     }
     try {
-      Command command = Command.builder().setConsoleName(null)
-          .setDirectory(ASPECT_LOCATION.getWorkspaceDirectory())
-          .addArguments(bazel, "version")
+      Command command = Command.builder(consoleFactory).setConsoleName(null)
+          .setDirectory(aspectLocation.getWorkspaceDirectory()).addArguments(bazel, "version")
           .setStdoutLineSelector((s) -> s.startsWith("Build label:") ? s.substring(13) : null)
           .build();
       if (command.run() != 0) {
@@ -150,9 +161,8 @@
     private BazelInstance(File workspaceRoot)
         throws IOException, InterruptedException, BazelNotFoundException {
       this.workspaceRoot = workspaceRoot;
-      this.packagePath =
-          String.join("", runBazel("info", "package_path")) + ":"
-              + ASPECT_LOCATION.getWorkspaceDirectory().toString();
+      this.packagePath = String.join("", runBazel("info", "package_path")) + ":"
+          + aspectLocation.getWorkspaceDirectory().toString();
       this.execRoot = new File(String.join("", runBazel("info", "execution_root")));
     }
 
@@ -190,7 +200,7 @@
         throws IOException, InterruptedException, BazelNotFoundException {
       return BazelCommand.this.runBazelAndGetErrorLines(ConsoleType.WORKSPACE, workspaceRoot,
           ImmutableList.<String>builder().add("build").add("--package_path", packagePath)
-              .addAll(ASPECT_OPTIONS).addAll(targets).build(),
+              .addAll(aspectOptions).addAll(targets).build(),
           // Strip out the artifact list, keeping the e4b-build.json files.
           t -> t.startsWith(">>>") ? (t.endsWith(".e4b-build.json") ? t.substring(3) : "") : null);
     }
@@ -236,7 +246,7 @@
         throws IOException, InterruptedException, BazelNotFoundException {
       return BazelCommand.this.runBazel(workspaceRoot,
           ImmutableList.<String>builder().add("build", "--package_path", packagePath)
-              .addAll(BUILD_OPTIONS).add(extraArgs).addAll(targets).build());
+              .addAll(buildOptions).add(extraArgs).addAll(targets).build());
     }
 
     /**
@@ -248,7 +258,7 @@
         throws IOException, InterruptedException, BazelNotFoundException {
       return BazelCommand.this.runBazel(workspaceRoot,
           ImmutableList.<String>builder().add("test").add("--package_path", packagePath)
-              .addAll(BUILD_OPTIONS).add(extraArgs).addAll(targets).build());
+              .addAll(buildOptions).add(extraArgs).addAll(targets).build());
     }
 
     /**
@@ -286,8 +296,7 @@
                 ImmutableList.<String>builder().add("query", packageName + ":*").build(), line -> {
                   int i = line.indexOf(':');
                   String s = line.substring(i + 1);
-                  return !s.isEmpty() && s.startsWith(targetPrefix)
-                      ? (packageName + ":" + s)
+                  return !s.isEmpty() && s.startsWith(targetPrefix) ? (packageName + ":" + s)
                       : null;
                 }));
         if ("all".startsWith(targetPrefix)) {
@@ -302,8 +311,7 @@
         int lastSlash = string.lastIndexOf('/');
         final String prefix = lastSlash > 0 ? string.substring(0, lastSlash + 1) : "";
         final String suffix = lastSlash > 0 ? string.substring(lastSlash + 1) : string;
-        final String directory = (prefix.isEmpty() || prefix.equals("//"))
-            ? ""
+        final String directory = (prefix.isEmpty() || prefix.equals("//")) ? ""
             : prefix.substring(string.startsWith("//") ? 2 : 0, prefix.length() - 1);
         File file = directory.isEmpty() ? workspaceRoot : new File(workspaceRoot, directory);
         ImmutableList.Builder<String> builder = ImmutableList.builder();
@@ -312,7 +320,7 @@
           return f.getName().startsWith(suffix) && f.isDirectory()
           // ...that does not start with '.'...
               && !f.getName().startsWith(".")
-              // ...and is not a Bazel convenience link
+          // ...and is not a Bazel convenience link
               && (!file.equals(workspaceRoot) || !f.getName().startsWith("bazel-"));
         });
         if (files != null) {
@@ -341,29 +349,29 @@
     return null;
   }
 
-  private ImmutableList<String> runBazelAndGetOuputLines(ConsoleType type, File directory,
-      List<String> args) throws IOException, InterruptedException, BazelNotFoundException {
+  private List<String> runBazelAndGetOuputLines(ConsoleType type, File directory, List<String> args)
+      throws IOException, InterruptedException, BazelNotFoundException {
     return runBazelAndGetOuputLines(type, directory, args, (t) -> t);
   }
 
-  private synchronized ImmutableList<String> runBazelAndGetOuputLines(ConsoleType type,
-      File directory, List<String> args, Function<String, String> selector)
+  private synchronized List<String> runBazelAndGetOuputLines(ConsoleType type, File directory,
+      List<String> args, Function<String, String> selector)
       throws IOException, InterruptedException, BazelNotFoundException {
-    Command command = Command.builder().setConsoleName(getConsoleName(type, directory))
-        .setDirectory(directory).addArguments(getBazelPath()).addArguments(args)
-        .setStdoutLineSelector(selector).build();
+    Command command = Command.builder(consoleFactory)
+        .setConsoleName(getConsoleName(type, directory)).setDirectory(directory)
+        .addArguments(getBazelPath()).addArguments(args).setStdoutLineSelector(selector).build();
     if (command.run() == 0) {
       return command.getSelectedOutputLines();
     }
     return ImmutableList.of();
   }
 
-  private synchronized ImmutableList<String> runBazelAndGetErrorLines(ConsoleType type,
-      File directory, List<String> args, Function<String, String> selector)
+  private synchronized List<String> runBazelAndGetErrorLines(ConsoleType type, File directory,
+      List<String> args, Function<String, String> selector)
       throws IOException, InterruptedException, BazelNotFoundException {
-    Command command = Command.builder().setConsoleName(getConsoleName(type, directory))
-        .setDirectory(directory).addArguments(getBazelPath()).addArguments(args)
-        .setStderrLineSelector(selector).build();
+    Command command = Command.builder(consoleFactory)
+        .setConsoleName(getConsoleName(type, directory)).setDirectory(directory)
+        .addArguments(getBazelPath()).addArguments(args).setStderrLineSelector(selector).build();
     if (command.run() == 0) {
       return command.getSelectedErrorLines();
     }
@@ -373,9 +381,9 @@
   private synchronized int runBazel(ConsoleType type, File directory, List<String> args,
       OutputStream stdout, OutputStream stderr)
       throws IOException, InterruptedException, BazelNotFoundException {
-    return Command.builder().setConsoleName(getConsoleName(type, directory)).setDirectory(directory)
-        .addArguments(getBazelPath()).addArguments(args).setStandardOutput(stdout)
-        .setStandardError(stderr).build().run();
+    return Command.builder(consoleFactory).setConsoleName(getConsoleName(type, directory))
+        .setDirectory(directory).addArguments(getBazelPath()).addArguments(args)
+        .setStandardOutput(stdout).setStandardError(stderr).build().run();
   }
 
   private int runBazel(File directory, List<String> args)
diff --git a/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/command/Command.java b/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/command/Command.java
index 889f237..594fa39 100644
--- a/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/command/Command.java
+++ b/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/command/Command.java
@@ -32,23 +32,18 @@
  */
 final class Command {
 
-  // TODO: inject
-  private final CommandConsoleFactory consoleFactory = new CommandConsoleFactoryImpl();
-
   private final File directory;
   private final ImmutableList<String> args;
   private final SelectOutputStream stdout;
   private final SelectOutputStream stderr;
   private boolean executed = false;
 
-  private Command(String consoleName, File directory, ImmutableList<String> args,
+  private Command(CommandConsole console, File directory, ImmutableList<String> args,
       Function<String, String> stdoutSelector, Function<String, String> stderrSelector,
       OutputStream stdout, OutputStream stderr) throws IOException {
     this.directory = directory;
     this.args = args;
-    if (consoleName != null) {
-      CommandConsole console = consoleFactory.get(consoleName,
-          "Running " + String.join(" ", args) + " from " + directory.toString());
+    if (console != null) {
       if (stdout == null) {
         stdout = console.createOutputStream();
       }
@@ -135,10 +130,12 @@
     private OutputStream stderr = null;
     private Function<String, String> stdoutSelector;
     private Function<String, String> stderrSelector;
+    private final CommandConsoleFactory consoleFactory;
 
-    private Builder() {
+    private Builder(final CommandConsoleFactory consoleFactory) {
       // Default to the current working directory
       this.directory = new File(System.getProperty("user.dir"));
+      this.consoleFactory = consoleFactory;
     }
 
     /**
@@ -243,7 +240,11 @@
      */
     public Command build() throws IOException {
       Preconditions.checkNotNull(directory);
-      return new Command(consoleName, directory, args.build(), stdoutSelector, stderrSelector,
+      ImmutableList<String> args = this.args.build();
+      CommandConsole console = consoleName == null ? null
+          : consoleFactory.get(consoleName,
+              "Running " + String.join(" ", args) + " from " + directory.toString());
+      return new Command(console, directory, args, stdoutSelector, stderrSelector,
           stdout, stderr);
     }
   }
@@ -251,7 +252,7 @@
   /**
    * Returns a {@link Builder} object to use to create a {@link Command} object.
    */
-  static Builder builder() {
-    return new Builder();
+  public static Builder builder(CommandConsoleFactory consoleFactory) {
+    return new Builder(consoleFactory);
   }
 }
diff --git a/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/preferences/BazelPreferencePage.java b/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/preferences/BazelPreferencePage.java
index 02ffad9..207716c 100644
--- a/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/preferences/BazelPreferencePage.java
+++ b/com.google.devtools.bazel.e4b/src/com/google/devtools/bazel/e4b/preferences/BazelPreferencePage.java
@@ -15,7 +15,6 @@
 package com.google.devtools.bazel.e4b.preferences;
 
 import com.google.devtools.bazel.e4b.Activator;
-import com.google.devtools.bazel.e4b.command.BazelCommand;
 import com.google.devtools.bazel.e4b.command.BazelNotFoundException;
 import org.eclipse.jface.preference.FieldEditorPreferencePage;
 import org.eclipse.jface.preference.FileFieldEditor;
@@ -40,7 +39,7 @@
     @Override
     protected boolean doCheckState() {
       try {
-        BazelCommand.checkVersion(getTextControl().getText());
+        Activator.getDefault().getCommand().checkVersion(getTextControl().getText());
         return true;
       } catch (BazelNotFoundException e) {
         setErrorMessage(e.getMessage());