confset

1. The problem

Sharing a setting across tools requires more than sharing a file. Each tool has its own keys, supported formats, and filename precedence. A generator that emits valid JSON can still produce a file the intended tool never loads. Confset pairs Pkl values with native destinations such as .oxlintrc.json, rustfmt.toml, and knip.json. ^[1]

Persistent output also creates an ownership problem. A later generation must distinguish its own previous output from a file a maintainer has edited. Changing formats can leave an older configuration in place that shadows the replacement. Confset checks those cases before writing. ^[1]

2. The design

Confset embeds the Rust Pkl evaluator, pklr, and a versioned package containing its schema, built-in producers, and rendering helpers. The matching package evaluates offline. Twenty producers describe supported formats, canonical filenames, and competing configurations. Pkl amendments and functions compute the final values; JSON, YAML, TOML, and INI renderers preserve representable data. A Pkl function can produce custom text and companion files. ^{[1] [2]}

The CLI selects an explicit configuration, an environment override, the nearest ancestor confset.pkl, or the operating system's user configuration file. Nested projects can select their own entry point, and an entry point can import or amend modules at any depth. Relative outputs belong to the selected project's directory. A root invocation does not recursively run independent child entry points. ^[1]

Generation compiles the complete output set and checks destinations before publishing. Project-local state records output paths and content hashes. A writer lock coordinates generation and cleanup; staged replacements and a journal support recovery after interruption. Unchanged files retain their timestamps. When a declaration disappears or changes format, Confset removes only obsolete outputs that still match their recorded content. ^[3]

Watch mode follows local inputs, handles atomic editor saves, and discards superseded compilation results. Invalid edits leave the previous outputs in place, and a later save can recover. Stopping the watcher leaves its last successful files available to tools. The optional managed gitignore block follows the published output set without changing the Git index. ^{[1] [4]}

3. Alternatives

The relevant distinction is the requirement each approach serves.

4. Boundaries & adoption

Configuration validation checks Confset's schema, representability, paths, and conflicts. The native tools remain responsible for validating their option names and meanings. JavaScript and TypeScript emitters and runtime callbacks are outside the supported model; Pkl computations finish before native files are loaded. ^[1]

Publication replaces each file atomically, but readers can observe a mixture of old and new files during an update across several destinations. Preserve the .confset state directory: matching bytes alone are not evidence that an existing file belongs to the generator. Cleanup preserves modified or ambiguous files and reports them for review. ^{[1] [3]}

The verification suite exercises native tool discovery and the actual Oxlint and Oxfmt language servers through an LSP client. Those protocol checks cover configuration reload behavior; they do not establish every editor extension's UI behavior. Release jobs build and run native archives on macOS, Windows, and GNU and musl Linux for amd64 and arm64, then test Cargo Binstall and mise installations. ^{[7] [8]}