Plain-English Explanation: serde-starlark

If you're building software with Bazel, Buck, Pants, or Please, you need to write configuration files that describe your build targets in a language called Starlark. This library automates that process by letting you write Rust code that generates valid Starlark configuration files automatically.

Instead of manually writing and maintaining Starlark build files, you can define your build targets as Rust structs (the basic data structures in Rust), serialize them, and get properly formatted Starlark output. For example, you might define a Rust struct that represents a library build target, populate it with details like the source files and dependencies, and the tool converts it into the exact Starlark syntax your build system expects. This is especially useful if you're generating build configurations dynamically or need to maintain them programmatically.

The tool uses a well-known Rust pattern called Serde, which is a framework for converting Rust data structures into other formats. In this case, instead of converting to JSON or YAML, it converts to Starlark. The mapping is straightforward: Rust numbers and strings become Starlark numbers and strings, collections become arrays and maps, and struct definitions become function calls with named arguments. The README includes examples showing how a simple Rust struct for a library target translates into a clean, readable Starlark build rule.

This would appeal to anyone who needs to manage Bazel or Buck build configurations programmatically—for instance, build infrastructure engineers who need to generate hundreds of similar build targets, or teams that want to define their build rules using type-safe Rust code instead of writing Starlark by hand. The main advantage is type safety and automation: Rust's compiler catches mistakes before your build configuration is even generated.