dddlint

Polyglot ubiquitous language linter. Reads class, function, method, and type names across 306 languages and enforces them against a domain vocabulary — banned terms, non-canonical synonyms, and one concept spelled multiple ways.

Works with any language tree-sitter recognises, without per-language queries. Slots into pre-commit hooks, CI pipelines, and coding agent loops via a non-zero exit code on findings. Ships with an LSP server for inline editor diagnostics and rename code actions.

📖 Full documentation

Install

uv add dddlint

Quick start

# lint current directory (looks for dddlint.yaml)
dddlint lint

# lint a specific path
dddlint lint src/

# open an interactive language graph in the browser
dddlint html

# start the LSP server (stdio)
dddlint lsp

Config

Place dddlint.yaml at the project root. When a path is passed to lint or html, the config is looked up in that directory first, then falls back to the current working directory.

similarity_threshold: 0.85   # Jaccard threshold for drift detection
enforce_canonical: true       # flag alias terms in addition to forbidden ones

# terms that must never appear in a definition name
forbidden:
  - util
  - helper
  - manager

# canonical terms and their aliases
synonyms:
  - canonical: customer
    aliases: [client, user, accountholder]
  - canonical: order
    aliases: [purchase, transaction]

# high-level business domains
domains:
  - name: commerce
    include: ["**/commerce/**"]
    synonyms:
      - canonical: order
        aliases: [purchase]

# bounded contexts — same structure as domains, applied after (context wins on conflict)
contexts:
  - name: billing
    include: ["**/billing/**"]
    forbidden: [discount]
    synonyms:
      - canonical: invoice
        aliases: [bill, statement]

Global rules apply everywhere. Domain rules apply to matching paths. Context rules apply after domains, so a context can override a domain synonym.

Rules

Rule	Severity	Description
forbidden	error	A definition name contains a banned term
alias	warning	A definition uses a non-canonical synonym — includes a rename suggestion
drift	info	The same concept is spelled multiple ways across the codebase
config:forbidden-canonical-clash	error	A term is both forbidden and a canonical synonym
config:alias-conflict	warning	The same alias maps to different canonicals in different scopes
config:duplicate-name	info	Two domains or contexts have suspiciously similar names

Config rules are checked against dddlint.yaml itself on every run.

LSP

The LSP server publishes diagnostics on file open and save, scanning the entire workspace each time so cross-file drift is always caught. Alias findings include a code action to rename the identifier to the canonical term with case preserved (ClientRepo → CustomerRepo, get_client → get_customer).

Neovim — add to init.lua:

vim.api.nvim_create_autocmd("BufReadPost", {
  callback = function(args)
    local root = vim.fs.root(args.buf, { "dddlint.yaml" })
    if root then
      vim.lsp.start({
        name = "dddlint",
        cmd = { "dddlint", "lsp" },
        root_dir = root,
      }, { bufnr = args.buf })
    end
  end,
})

The autocmd fires on every buffer, attaches only when dddlint.yaml is found, and is language-agnostic — no filetype list required.

VS Code — via a generic LSP client extension:

{
  "lsp.servers": {
    "dddlint": {
      "command": ["uvx", "dddlint", "lsp"],
      "filetypes": ["*"]
    }
  }
}

Helix — .helix/languages.toml:

[language-server.dddlint]
command = "dddlint"
args = ["lsp"]

Language support

Extraction is powered by tree-sitter-language-pack, which covers 306 languages including:

Ada · Agda · Arduino · Bash · C · C++ · C# · Clojure · COBOL · Crystal · CSS · D · Dart · Dockerfile · Elixir · Elm · Erlang · F# · Fortran · GDScript · GLSL · Go · GraphQL · Groovy · Hack · Haskell · HCL · HTML · Java · JavaScript · Julia · Kotlin · Lean · Lua · MATLAB · Mojo · Nix · OCaml · Odin · Pascal · Perl · PHP · PowerShell · Prolog · Python · R · Racket · Ruby · Rust · Scala · Scheme · Solidity · SQL · Svelte · Swift · Terraform · TLA+ · TOML · TypeScript · V · VHDL · Vim · Vue · WebAssembly · XML · YAML · Zig — and 243 more.

CI

# .github/workflows/dddlint.yml
- run: uvx dddlint lint

Exit code is 0 when clean, 1 when findings exist.

Pre-commit

# .pre-commit-config.yaml
repos:
  - repo: local
    hooks:
      - id: dddlint
        name: dddlint
        entry: dddlint lint
        language: python
        pass_filenames: false

Offline use

The language pack downloads parsers on first use. For CI or air-gapped runs, warm the cache in the image:

python -c "import tree_sitter_language_pack as t; t.download_all()"