lymals

lymals is a parse-only language server for Lyma files ending in .lyma.

Status

The server currently supports stdio LSP lifecycle, document sync, diagnostics, configuration, workspace folders/file watching, local import/include/schema resolution, completion, hover, navigation, references, rename, symbols, formatting, semantic tokens, code actions, inlay hints, folding ranges, selection ranges, and safe commands.

Lyma evaluation is intentionally not shipped in v1. Embedded Lua is parsed/tokenized for editor features but never executed.

Install / run

Download release archives and checksums from GitHub releases, or build from source:

cargo build --release
target/release/lymals --version
target/release/lymals --stdio

See docs/packaging.md for release artifact names, checksum verification, and local release-equivalent builds.

Guardrail: v1 is binary-only. Do not publish crates, VSIX/editor packages, or GitHub releases until versioning, licensing, and release checksum validation are complete.

Useful flags:

lymals --version
lymals --print-config-schema
lymals --stdio --log-file /tmp/lymals.log

VS Code-compatible client setup

Use any generic LSP client extension that can launch a command over stdio. Configure it with:

{
  "languageserver": {
    "lyma": {
      "command": "/absolute/path/to/lymals",
      "args": ["--stdio"],
      "filetypes": ["lyma"],
      "rootPatterns": [".git"],
      "settings": { "lymals": { "evaluation": { "enabled": false } } }
    }
  }
}

Associate files matching *.lyma with the lyma language id.

See editors/vscode/README.md for binary-based VS Code-compatible setup notes.

Neovim setup

vim.api.nvim_create_autocmd({ "BufRead", "BufNewFile" }, {
  pattern = "*.lyma",
  callback = function(args)
    vim.bo[args.buf].filetype = "lyma"
  end,
})

vim.lsp.start({
  name = "lymals",
  cmd = { "/absolute/path/to/lymals", "--stdio" },
  root_dir = vim.fs.root(0, { ".git" }) or vim.fn.getcwd(),
  settings = { lymals = { evaluation = { enabled = false } } },
})

See editors/neovim.md for a reusable Neovim setup snippet.

Configuration

See docs/configuration.md. Defaults are safe: only file: schemes are allowed, absolute file URIs are blocked, imports are root-bounded, and evaluation is disabled/reserved.

Safety model

See docs/security.md. lymals blocks network/package schemes by default, rejects parent traversal, caps resolver depth/edges/file sizes, and keeps all editor features parse-only.

Feature matrix

See docs/feature-matrix.md for current support and parse-only semantics.

Troubleshooting

See docs/troubleshooting.md. The lymals.serverStatus command reports lifecycle/config status, and lymals.explainDiagnostic explains diagnostic codes.

Development

cargo fmt --all --check
cargo test
cargo test --all-features
cargo doc --workspace --all-features --no-deps

For the VS Code extension developer loop:

cargo build
# then in editors/vscode
npm install
npm run compile    # or: npm run watch

Open editors/vscode in VS Code, set lymalsExtension.server.path to ../../target/debug/lymals.exe on Windows or ../../target/debug/lymals on macOS/Linux, then press F5 to launch an Extension Development Host. Open Output > Lymals for client/LSP logs; use lymalsExtension.server.logFile and lymalsExtension.server.rustLog when you need server-side logging.

Dependency rationale and workflows are in docs/development.md. VS Code-specific setup notes are in editors/vscode/README.md. Upstream parser strategy is documented in docs/upstream-lyma.md.

Contributing

Contributions should stay within the v1 scope: binary-only releases, docs-only editor setup, and parse-only features that never execute Lua. Release/publishing changes must preserve the guardrail that artifacts are validated for versioning, licensing, and checksums before any publish/release action is introduced. See docs/development.md for local workflow, test commands, and PR expectations.