CONTRIBUTING.md

CONTRIBUTING.md

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+# Contributing to Miller
+
+Thanks for your interest in contributing! This page is a quick-start guide for code, test, and
+documentation contributions. It links out to more detailed docs rather than repeating them, so if
+something below feels thin, follow the link.
+
+## Asking questions / reporting issues
+
+* Questions and general discussion: [GitHub Discussions](https://github.com/johnkerl/miller/discussions)
+* Bug reports and feature requests: [GitHub Issues](https://github.com/johnkerl/miller/issues)
+* See also [notes on issue-labeling](https://github.com/johnkerl/miller/wiki/Issue-labeling).
+
+When filing a bug, please include your Miller version (`mlr --version`), OS, and a minimal repro
+(command line plus a few lines of sample input).
+
+## Getting the source and building
+
+```
+git clone https://github.com/johnkerl/miller
+cd miller
+make        # builds ./mlr
+make check  # runs unit + regression tests
+```
+
+Miller is written in Go (1.25+ as of July 2026) with no non-standard-library runtime dependencies.
+For build details beyond `make`/`go build`, see the [Building from
+source](https://miller.readthedocs.io/en/latest/build) doc and [README-dev.md](./README-dev.md).
+
+## Before opening a PR
+
+Run the full developer workflow:
+
+```
+make dev
+```
+
+This formats code, builds, runs unit and regression tests, and regenerates
+docs/man-pages, in the right order. A PR that passes this is in good shape to
+submit.
+
+A few conventions to follow:
+
+* Code should read like idiomatic, `go fmt`-clean Go. Miller favors clarity
+  over cleverness, including some acceptable code duplication: see
+  [README-dev.md: Source-code goals](./README-dev.md#source-code-goals).
+* Avoid line wraps at a terminal width of 120 columns, tabwidth 4.
+* Prose in docs/comments uses the Oxford comma.
+* Reference relevant issue numbers in commit messages where applicable.
+
+## Where to look depending on what you're changing
+
+* **Adding or fixing a built-in DSL function**: implement in `pkg/bifs/`,
+  add unit tests alongside, update `docs/src/`.
+* **Adding/changing a verb (transformer)**: see `pkg/transformers/` and the
+  directory-structure notes in [README-dev.md](./README-dev.md).
+* **Anything touching the DSL grammar** (`pkg/parsing/mlr.bnf`): see
+  [README-dev.md](./README-dev.md) for the `tools/build-dsl` regeneration step.
+* **Tests**: Miller's test suite is mostly scripted CLI invocations compared
+  against expected output, plus a smaller set of Go unit tests. See
+  [test/README.md](./test/README.md) for how to run and add cases.
+* **Documentation**: the published docs are generated from `docs/src/*.md.in`
+  files, not hand-edited `.md`. See [README-docs.md](./README-docs.md) for the
+  edit/preview/build loop.
+* **Performance work**: see [README-profiling.md](./README-profiling.md) for
+  profiling Miller itself, and [scripts/perf/README.md](./scripts/perf/README.md)
+  for the benchmark scripts used to produce the performance graphs in the docs.
+* **Background on the Go port** (history, design rationale, why Go over C):
+  see [README-go-port.md](./README-go-port.md). Not required reading to
+  contribute, but useful context for anything touching core internals like
+  `Mlrval` or the record-stream architecture.
+
+## Using an AI coding assistant
+
+If you're using Claude Code against this repo, [CLAUDE.md](./CLAUDE.md) has
+build/test commands and conventions written for that workflow. It's a
+supplement for AI-assisted contributions, not a replacement for this page.
+
+## License
+
+Miller is licensed under the [two-clause BSD license](./LICENSE.txt).
+Contributions are accepted under the same license.