@@ -0,0 +1,54 @@
+# Managed by .ores-lint/ - regenerated by the rollout script.
+name: ores-lint
+
+on:
+  pull_request:
+  workflow_dispatch:
+  # Add `push:` here once this repo's lint debt is paid down.
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Detect project types
+        id: detect
+        run: |
+          { [ -f package.json ] || git ls-files '*.js' '*.mjs' '*.cjs' '*.ts' '*.tsx' | grep -q .; } \
+            && echo "js=true" >> "$GITHUB_OUTPUT" || echo "js=false" >> "$GITHUB_OUTPUT"
+          { [ -f Cargo.toml ] || git ls-files '*.rs' | grep -q .; } \
+            && echo "rs=true" >> "$GITHUB_OUTPUT" || echo "rs=false" >> "$GITHUB_OUTPUT"
+          { [ -f pubspec.yaml ] || git ls-files '*.dart' | grep -q .; } \
+            && echo "dart=true" >> "$GITHUB_OUTPUT" || echo "dart=false" >> "$GITHUB_OUTPUT"
+          { [ -f gleam.toml ] || git ls-files '*.gleam' | grep -q .; } \
+            && echo "gleam=true" >> "$GITHUB_OUTPUT" || echo "gleam=false" >> "$GITHUB_OUTPUT"
+
+      # Node is the runner for ESLint and for the cross-language require-send
+      # scanner, so it is installed whenever any supported language is present.
+      - uses: actions/setup-node@v4
+        if: steps.detect.outputs.js == 'true' || steps.detect.outputs.rs == 'true' || steps.detect.outputs.dart == 'true' || steps.detect.outputs.gleam == 'true'
+        with:
+          node-version: '22'
+
+      # ESLint is a global tool here, not a repo dependency - so this job never
+      # runs `npm install` and never needs the repo's node_modules.
+      - name: Install eslint globally
+        if: steps.detect.outputs.js == 'true'
+        run: npm i -g eslint typescript-eslint
+
+      - name: Install clippy
+        if: steps.detect.outputs.rs == 'true'
+        run: rustup component add clippy || true
+
+      # Dart/Gleam SDKs are optional. When absent, dart.sh / gleam.sh skip
+      # with an actionable message; require-send.mjs still runs via Node.
+      - uses: dart-lang/setup-dart@v1
+        if: steps.detect.outputs.dart == 'true'
+        continue-on-error: true
+
+      - name: Run ores-lint
+        run: sh .ores-lint/lint.sh
+        env:
+          # Warn-only. Set to 1 here to make lint findings fail this repo's CI.
+          ORES_LINT_STRICT: '0'
@@ -0,0 +1,218 @@
+# ores-lint
+
+A vendored, dependency-free lint baseline for every JavaScript/TypeScript,
+Rust, Dart/Flutter and Gleam repo in the org fleet. Everything it needs is in
+this directory — there is nothing to install from a registry and nothing to
+keep in version sync.
+
+Only universally accepted linters are used as hosts:
+
+| language | host linter | custom house rules |
+|---|---|---|
+| TypeScript / JS | ESLint 9+ (flat config) | `ores/require-send`, `ores/semi` |
+| Rust | clippy | `implicit_return` house style; `#[must_use]` on log `Event`; require-send scanner |
+| Dart / Flutter | `dart analyze` | require-send scanner |
+| Gleam | `gleam format --check` + `gleam check` | require-send scanner |
+
+There is no ESLint-quality plugin host for Gleam, and Dart's `custom_lint` /
+Rust's `dylint` would pull registry packages into every repo. The one house
+rule that those hosts cannot express — **logger chains must end in `send()`** —
+is implemented as a vendored ESLint rule for TS and a small Node scanner for
+the other three languages.
+
+## Running it
+
+```sh
+sh .ores-lint/lint.sh      # lints whatever this repo contains
+sh .ores-lint/selftest.sh  # verifies the toolkit still works after a toolchain upgrade
+```
+
+For JS repos it is also wired into `npm run lint:ores`, and runs automatically
+before `npm run build` (`prebuild`) and before `npm publish` (`prepublishOnly`).
+
+## What it enforces
+
+**JavaScript / TypeScript** — via ESLint (flat config):
+
+| rule | why |
+|---|---|
+| `semi` | house style: semicolons are required, missing ones warn |
+| `ores/require-send` | a logging chain that reaches `.info()`/`.warn()`/… but never calls `.send()` or `.send(boolean)` builds an event that is never delivered |
+| correctness set | `eqeqeq`, `no-unreachable`, `no-dupe-keys`, `use-isnan`, `valid-typeof`, `no-async-promise-executor`, and similar low-false-positive checks |
+
+**Rust** — via clippy, plus rustc `#[must_use]` on ores-otel `Event`:
+
+| lint | why |
+|---|---|
+| `clippy::implicit_return` | house style: prefer an explicit `return` at tail position |
+| `clippy::correctness`, `clippy::suspicious` | real defects |
+| `unwrap_used`, `expect_used`, `panic_in_result_fn`, `todo`, `dbg_macro` | things that should not reach a publish |
+
+**Dart / Flutter** — via `dart analyze` (or `flutter analyze`). If the repo has
+no `analysis_options.yaml`, rollout drops a baseline of analyzer-shipped
+correctness lints. Existing files are never overwritten. Prefer
+`package:lints` / `package:flutter_lints` when the package already depends on
+them — those are the Dart equivalents of `eslint:recommended`.
+
+**Gleam** — via `gleam format --check` and `gleam check`. Unused values already
+catch many forgotten `send` calls; the scanner catches the rest (assigned
+events, unfinished pipes).
+
+**require-send (all four languages).** The ores-otel logger builds an event
+through method chaining (TS/Rust/Dart) or pipes (Gleam). Delivery is
+`send()`, `send(boolean)`, or `send_with_store(...)`. Forgetting that call
+means the event is built and then dropped — unless shutdown recovers it, which
+is a fallback, not the API. Tests that deliberately build unsent events are
+skipped unless `ORES_LINT_REQUIRE_SEND_INCLUDE_TESTS=1`.
+
+## Overriding a finding on one line
+
+This is expected. Some tests, shutdown-recovery fixtures, and rare control
+flow should not call `send()`. Use the comment that matches the host linter,
+or the unified ores-lint form which works in every language:
+
+```
+// ores-lint-disable-next-line require-send
+// ores-lint-disable-line require-send
+// ores-lint-disable-file require-send
+```
+
+Language-native equivalents, also honoured:
+
+| language | one-line override |
+|---|---|
+| TypeScript | `// eslint-disable-next-line ores/require-send` |
+| Rust (`#[must_use]`) | `#[allow(unused_must_use)]` on the next statement |
+| Dart analyzer | `// ignore: name_of_lint` (analyzer rules only; require-send uses the ores-lint form) |
+| Gleam | the ores-lint form above |
+
+Do not disable the rule for a whole file unless the file is a generated
+fixture. Prefer the next-line form.
+
+## The two things worth knowing
+
+
+**1. Implicit-return findings are capped.** `clippy::implicit_return` fires once
+per implicit return, which on a real crate is hundreds of identical lines. The
+lint stays fully enabled so nothing is missed, but `rust.sh` collapses it into a
+single warning showing at most 5 concrete locations plus `... and N more`. The
+same cap applies to every ESLint rule via `eslint/formatter.mjs`. Change it with
+`ORES_LINT_MAX_EXAMPLES`.
+
+**2. `clippy::needless_return` had to be disabled.** It ships enabled in
+clippy's default `style` group and warns on exactly the explicit returns this
+house style asks for. Enabling `implicit_return` without allowing
+`needless_return` makes the two lints contradict each other on every function in
+the crate. `selftest.sh` asserts this stays true.
+
+## Scope: sub-projects and repo boundaries
+
+The linter does **not** assume the repo root is the only project.
+
+- **Rust** — `rust.sh` finds every crate in the repo, including ones under
+  `apps/` or `clients/`. Crates that are workspace members of an already-linted
+  root are skipped (via `cargo metadata --no-deps`) so nothing is linted twice,
+  and findings from every crate are aggregated into **one** capped report.
+- **JS/TS** — a flat config at the repo root makes `eslint .` reach nested
+  packages, so the config goes in even when the JS lives in a subdirectory.
+
+**Nested git repositories are a hard boundary.** A repo checked out inside
+another repo gets its own ores-lint install; the parent must not lint it, or the
+same findings get reported twice under the wrong repo name and the same
+`package.json` gets wired with two conflicting relative paths. `rollout.mjs`
+records those boundaries in `.ores-lint/nested-repos.json`, and both halves of
+the linter read it.
+
+To exclude a repo entirely — vendored upstream forks, for instance — drop an
+empty `.ores-lint-ignore` file at its root.
+
+## Legacy config migration
+
+ESLint 9+ reads flat config **only**. Three older mechanisms are silently
+ignored, which means any repo still relying on them has not been linted at all:
+
+| legacy mechanism | status |
+|---|---|
+| `.eslintrc*` | ignored entirely; rules are dead |
+| `eslintConfig` key in `package.json` | ignored entirely |
+| `.eslintignore` | ignored, with a warning |
+
+`audit.mjs` reports every repo in each category. `.eslintignore` is ported
+automatically into flat-config `ignores` by `base.mjs` (gitignore semantics
+preserved), so its intent keeps applying. The other two need a human decision
+and are migrated per repo — porting the rules that still make sense, and saying
+in a comment which ones were dropped and why.
+
+## Warn-only, by design
+
+`lint.sh` exits 0 no matter what it finds. It is wired into build and publish
+hooks across hundreds of repos, so it is built to be incapable of breaking one
+unless a human opts in.
+
+To make findings blocking for a single repo, create `.ores-lint/local.sh`:
+
+```sh
+ORES_LINT_STRICT=1
+```
+
+`local.sh` is yours — the rollout script never overwrites it. Everything else in
+this directory is managed and will be replaced on the next rollout.
+
+## Knobs
+
+| variable | default | meaning |
+|---|---|---|
+| `ORES_LINT_MAX_EXAMPLES` | `5` | example locations shown per rule |
+| `ORES_LINT_STRICT` | `0` | `1` makes any finding exit non-zero |
+| `ORES_LINT_SKIP_JS` / `ORES_LINT_SKIP_RUST` / `ORES_LINT_SKIP_DART` / `ORES_LINT_SKIP_GLEAM` | `0` | skip one language host |
+| `ORES_LINT_SKIP_REQUIRE_SEND` | `0` | skip the cross-language send() scanner |
+| `ORES_LINT_REQUIRE_SEND_INCLUDE_TESTS` | `0` | `1` also scans `test/` / `*_test.dart` / etc. |
+| `ORES_LINT_RUST_ALL_TARGETS` | `0` | `1` also lints tests/benches/examples |
+| `ORES_LINT_RUST_EXTRA` | — | extra flags appended to the clippy invocation |
+
+## Graceful degradation
+
+Nothing here is allowed to fail loudly for an environmental reason. ESLint not
+installed, too old, clippy not installed, dart/flutter not installed, gleam not
+installed, no TypeScript parser available, crate deps not fetchable — each is
+reported as an actionable skip, not an error.
+Repo-specific ESLint config that already existed is never overwritten.
+The same is true of `analysis_options.yaml`.
+
+CI follows the same model: the workflow runs `npm i -g eslint typescript-eslint`
+and never runs `npm install` for the repo itself, so linting a PR does not
+require the repo's dependency tree to resolve.
+
+## Per-repo customisation
+
+`eslint.config.mjs` at the repo root takes options:
+
+```js
+export default await oresConfig({
+  requireSend: { loggerNames: ['myLogger'], terminalMethods: ['send', 'flush'] },
+  rules: { 'no-console': 'warn' },
+  ignores: ['**/generated/**'],
+});
+```
+
+Once you edit that file the rollout script leaves it alone.
+
+---
+
+## Fleet operations (from the `codes` directory)
+
+```sh
+node .ores-lint-toolkit/audit.mjs                 # report the fleet's lint posture
+node .ores-lint-toolkit/audit.mjs --json out.json # ...as machine-readable data
+node .ores-lint-toolkit/rollout.mjs --dry-run     # preview
+node .ores-lint-toolkit/rollout.mjs               # install / re-install everywhere
+node .ores-lint-toolkit/rollout.mjs --only ores-otel
+node .ores-lint-toolkit/rollout.mjs --shard 0/8   # one slice of a fleet-wide run
+node .ores-lint-toolkit/verify.mjs                # assert every repo is correctly installed
+```
+
+A full rollout over ~900 repos takes a few minutes. `--shard k/n` splits it into
+bounded chunks, which matters when the runner has a per-command time limit.
+
+Re-run the rollout after editing anything in `.ores-lint-toolkit/` — it is
+idempotent and propagates the change to every repo.
@@ -0,0 +1 @@
+1.3.0
@@ -0,0 +1,46 @@
+#!/bin/sh
+# ores-lint shared configuration. Sourced by lint.sh, js.sh and rust.sh.
+# Every value can be overridden from the environment, or per repo in local.sh.
+
+# Maximum number of concrete example locations shown for any one rule.
+: "${ORES_LINT_MAX_EXAMPLES:=5}"
+
+# Warn-only by default: lint.sh exits 0 no matter what it finds.
+# Flip to 1 (per repo, or in CI) once a repo's debt is paid down.
+: "${ORES_LINT_STRICT:=0}"
+
+: "${ORES_LINT_SKIP_RUST:=0}"
+: "${ORES_LINT_SKIP_JS:=0}"
+: "${ORES_LINT_SKIP_DART:=0}"
+: "${ORES_LINT_SKIP_GLEAM:=0}"
+: "${ORES_LINT_SKIP_REQUIRE_SEND:=0}"
+: "${ORES_LINT_REQUIRE_SEND_INCLUDE_TESTS:=0}"
+
+# How deep to search for nested sub-projects (crates and packages). Repos here
+# routinely hold crates under apps/ and clients/ that a root-only lint misses.
+: "${ORES_LINT_DEPTH:=5}"
+
+# Include tests/benches/examples in the Rust pass. Off by default so the
+# pre-publish signal is about shipped code.
+: "${ORES_LINT_RUST_ALL_TARGETS:=0}"
+
+# Minimum ESLint major version. Flat config needs 9+. ESLint is expected to be
+# installed GLOBALLY, once - see required-tools.json. Nothing is ever installed
+# into a repo's node_modules.
+: "${ORES_LINT_ESLINT_MIN_MAJOR:=9}"
+
+# The exact clippy diagnostic text for `clippy::implicit_return`. selftest.sh
+# verifies this still matches, so a future clippy rewording surfaces as a test
+# failure rather than as a silently empty report.
+: "${ORES_LINT_IMPLICIT_RETURN_MSG:=missing \`return\` statement}"
+
+export ORES_LINT_MAX_EXAMPLES ORES_LINT_STRICT ORES_LINT_SKIP_RUST ORES_LINT_SKIP_JS
+export ORES_LINT_SKIP_DART ORES_LINT_SKIP_GLEAM ORES_LINT_SKIP_REQUIRE_SEND
+export ORES_LINT_REQUIRE_SEND_INCLUDE_TESTS
+export ORES_LINT_DEPTH ORES_LINT_RUST_ALL_TARGETS ORES_LINT_ESLINT_MIN_MAJOR
+export ORES_LINT_IMPLICIT_RETURN_MSG
+
+# Repo-local overrides, never overwritten by the rollout script. Sourced last so
+# anything set here wins.
+ORES_LINT_CFG_DIR=$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)
+[ -f "$ORES_LINT_CFG_DIR/local.sh" ] && . "$ORES_LINT_CFG_DIR/local.sh"