| # Configurations |
| |
| A build setting is a single piece of [configuration](/versions/6.6.6/rules/rules#configurations) information. |
| |
| Like all rules, build setting rules have [implementation functions](https://bazel.build/versions/6.6.6/rules/rules#implementation-function). |
| |
| In Starlark, transitions are defined much like rules, with a defining |
| `transition()` [function](lib/transition#transition) and an implementation function. |
| |
| See [Accessing attributes with transitions](#accessing-attributes-with-transitions) |
| for how to read these keys. |
