Custom recipes

Use a recipe when your build needs another step, such as running a compiled program to generate a report. The step can consume an existing package's output without repeating how that package is built.

Suppose app is an executable built with the native Rust preview. Create recipe/BUILD.bsmr:

genrule(
    name = "report",
    out = "report.txt",
    cmd = "$(exe root//app:app) > $OUT",
)

Then build the report:

bsmr build recipe:report --show-output

root//app:app identifies the executable in the app package. $(exe ...) tracks its executable and runtime inputs. $OUT is the output path BSMR assigns to report.txt. BSMR builds the application before running the report step.

Another action can declare recipe:report as an input. Each step exposes outputs for the next step, so BSMR can schedule and cache them independently. Reusable Starlark functions can compose the same declarations.

Declare every tool, input, output, and environment value that affects the step. A build that reads undeclared state cannot safely reuse cached results. See caching for the complete input contract.

An explicit BUILD.bsmr defines its whole package and takes precedence over native inference. Put recipes in a separate directory when the application should keep using its language files as the build definition.

Use bsmr build --help for build options. Run bsmr docs --help to find API documentation commands, or open the command-line reference for queries and inspection commands.

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