From beccbbcf11795dc533c160144543e8ab1214ed2a Mon Sep 17 00:00:00 2001
From: Jakob Heuser <jakob@codedrift.com>
Date: Sun, 20 Sep 2026 14:27:46 -0700
Subject: [PATCH] feat(detect): recognize oxlint alongside eslint, biome and
 stylelint

---
 .changeset/detect-oxlint.md                   |  5 ++
 .../2026-09-20-detect-oxlint/proposal.md      | 32 +++++++++
 .../specs/cli-detect/spec.md                  | 66 +++++++++++++++++++
 .../archive/2026-09-20-detect-oxlint/tasks.md | 15 +++++
 openspec/specs/cli-detect/spec.md             | 11 +++-
 packages/cli/src/detect/scan.ts               | 14 ++++
 packages/cli/test/detect.test.ts              | 29 ++++++++
 7 files changed, 171 insertions(+), 1 deletion(-)
 create mode 100644 .changeset/detect-oxlint.md
 create mode 100644 openspec/changes/archive/2026-09-20-detect-oxlint/proposal.md
 create mode 100644 openspec/changes/archive/2026-09-20-detect-oxlint/specs/cli-detect/spec.md
 create mode 100644 openspec/changes/archive/2026-09-20-detect-oxlint/tasks.md

diff --git a/.changeset/detect-oxlint.md b/.changeset/detect-oxlint.md
new file mode 100644
index 00000000..ae91bc52
--- /dev/null
+++ b/.changeset/detect-oxlint.md
@@ -0,0 +1,5 @@
+---
+"@taskless/cli": patch
+---
+
+`taskless detect` recognizes oxlint alongside eslint, biome and stylelint, from `.oxlintrc.json`, `.oxlintrc.jsonc`, `oxlint.config.ts`, `oxlint.config.mts`, or an `oxlint` entry in `package.json`.
diff --git a/openspec/changes/archive/2026-09-20-detect-oxlint/proposal.md b/openspec/changes/archive/2026-09-20-detect-oxlint/proposal.md
new file mode 100644
index 00000000..dd8a919e
--- /dev/null
+++ b/openspec/changes/archive/2026-09-20-detect-oxlint/proposal.md
@@ -0,0 +1,32 @@
+## Why
+
+`taskless detect` recognizes eslint, biome and stylelint for JavaScript and TypeScript, but not oxlint. A repo that has moved to oxlint reports no JS linter, so `detect` output and everything downstream that reads it (`init`, the `route` recipe) treats the project as unlinted. oxlint is where a growing share of JS repos are heading for the static tier, and its plugin architecture cannot do cross-file rules, which makes an oxlint repo exactly the kind of project where Taskless runtime rules add something the linter cannot. Detect needs to see it.
+
+## What Changes
+
+- A new `oxlint` entry in `LINTER_SIGNALS` (`packages/cli/src/detect/scan.ts`), shaped like `biome`: languages JavaScript + TypeScript, config files `.oxlintrc.json`, `.oxlintrc.jsonc`, `oxlint.config.ts`, `oxlint.config.mts`, dependency `oxlint` matched against `package.json` only.
+- The config list is the set oxlint auto-discovers per https://oxc.rs/docs/guide/usage/linter/config.html ("Oxlint automatically looks for a `.oxlintrc.json`, `.oxlintrc.jsonc`, `oxlint.config.ts`, or `oxlint.config.mts` in the current working directory"). `oxlint.config.{js,mjs,cjs}` are accepted only through an explicit `-c` flag and are deliberately excluded.
+- The `cli-detect` spec's example list for "Linter configs are detected from disk" names `.oxlintrc.json`, and a scenario covers oxlint from either signal.
+- Tests: `.oxlintrc.json` alone detects oxlint; `oxlint` only in `devDependencies` detects oxlint; an eslint-only repo does not report oxlint.
+
+Nothing here is **BREAKING**. Pre-1.0, an added linter signal is a `patch`.
+
+## Capabilities
+
+### New Capabilities
+
+None.
+
+### Modified Capabilities
+
+- `cli-detect`: the "Detect scans deterministic repo signals only" requirement's example config list gains `.oxlintrc.json`, and a new scenario states that oxlint is detected from its config file or its `package.json` dependency.
+
+## Impact
+
+- `packages/cli/src/detect/scan.ts`: one new `LinterSignal` entry.
+- `packages/cli/test/detect.test.ts`: three new cases.
+- `packages/cli/src/agent/detect.md`: untouched; it does not enumerate the JS linters.
+
+## Delivery shape
+
+**Single PR.** The change is one signal entry, its tests, the spec delta and the archive; it fits one reviewable diff and is safe in production on its own.
diff --git a/openspec/changes/archive/2026-09-20-detect-oxlint/specs/cli-detect/spec.md b/openspec/changes/archive/2026-09-20-detect-oxlint/specs/cli-detect/spec.md
new file mode 100644
index 00000000..6c698262
--- /dev/null
+++ b/openspec/changes/archive/2026-09-20-detect-oxlint/specs/cli-detect/spec.md
@@ -0,0 +1,66 @@
+## MODIFIED Requirements
+
+### Requirement: Detect scans deterministic repo signals only
+
+The `detect` command SHALL emit only deterministic signals derived from files on
+disk: configured linters, detected languages, and the styles of the repo's own
+existing rules. It SHALL NOT perform any LLM inference and SHALL NOT match the
+request against any catalog of known packaged linter rules.
+
+Detection follows a languages → linters flow: languages are inferred first, and
+a linter's dependency evidence is then read from the manifest of that linter's
+own language (a node dependency from `package.json`, a Python dependency from
+`pyproject.toml`/`requirements.txt`) rather than conflating ecosystems. A
+recognized linter config file on disk is honored regardless of the languages
+inferred.
+
+#### Scenario: Linter configs are detected from disk
+
+- **WHEN** the working directory contains a recognized linter config (for
+  example `.eslintrc*`, `eslint.config.js`, `ruff.toml`, a `[tool.ruff]` block in
+  `pyproject.toml`, `.rubocop.yml`, `biome.json`, `.oxlintrc.json`, or
+  `stylelint` config)
+- **THEN** `detect --json` SHALL report each configured linter it found
+
+#### Scenario: Languages are reported
+
+- **WHEN** `detect --json` runs in a repository
+- **THEN** the output SHALL include the languages inferred from manifest and
+  marker files present on disk and from the linters detected
+
+#### Scenario: A linter dependency is sourced from its own language's manifest
+
+- **WHEN** a dependency-evidenced linter (for example `ruff`) is named only in a
+  manifest belonging to a different language (for example `package.json`)
+- **THEN** `detect --json` SHALL NOT report that linter from the mismatched
+  manifest
+
+#### Scenario: oxlint is detected from its config or its dependency
+
+- **WHEN** the working directory contains one of the config files oxlint
+  discovers on its own (`.oxlintrc.json`, `.oxlintrc.jsonc`, `oxlint.config.ts`,
+  `oxlint.config.mts`), or names `oxlint` as a dependency in `package.json`
+- **THEN** `detect --json` SHALL report `oxlint` as a JavaScript/TypeScript linter
+- **AND** a repository configured only for eslint SHALL NOT report `oxlint`
+
+#### Scenario: Configs in monorepo sub-packages are detected
+
+- **WHEN** a linter config or language manifest lives in a sub-package rather
+  than the repository root (for example `packages/api/.eslintrc.json`)
+- **THEN** `detect --json` SHALL detect it and SHALL carry the path it was found
+  at in the linter's evidence
+- **AND** the scan SHALL prune a curated set of ignored directories (for example
+  `node_modules`, `.git`, build output) and SHALL bound traversal depth
+
+#### Scenario: The repo's own rule styles are surfaced
+
+- **WHEN** the working directory contains existing rule definitions (for example
+  custom linter rules or `.taskless/rules/`)
+- **THEN** `detect --json` SHALL surface a description of those existing rule
+  styles for downstream authoring
+
+#### Scenario: No packaged-rule catalog matching
+
+- **WHEN** `detect --json` runs
+- **THEN** the output SHALL NOT claim a request maps to a specific named packaged
+  rule (such matching is left to the authoring recipe, not the command)
diff --git a/openspec/changes/archive/2026-09-20-detect-oxlint/tasks.md b/openspec/changes/archive/2026-09-20-detect-oxlint/tasks.md
new file mode 100644
index 00000000..2f7d4e88
--- /dev/null
+++ b/openspec/changes/archive/2026-09-20-detect-oxlint/tasks.md
@@ -0,0 +1,15 @@
+## 1. Implementation
+
+- [x] 1.1 Verify against https://oxc.rs/docs/guide/usage/linter/config.html which config filenames oxlint discovers on its own; exclude any `oxlint.config.*` variant that is only reachable through `-c`.
+- [x] 1.2 Add the `oxlint` entry to `LINTER_SIGNALS` in `packages/cli/src/detect/scan.ts`, shaped like `biome`, with a comment naming the excluded filenames and why.
+- [x] 1.3 Add tests in `packages/cli/test/detect.test.ts`: `.oxlintrc.json` alone detects oxlint; `oxlint` in `devDependencies` alone detects oxlint; an eslint-only repo does not report oxlint.
+- [x] 1.4 Add `.changeset/detect-oxlint.md` (`patch`).
+
+## 2. Spec
+
+- [x] 2.1 Write the `cli-detect` delta restating the full "Detect scans deterministic repo signals only" requirement with every existing scenario, the updated example list, and the new oxlint scenario.
+- [x] 2.2 `pnpm openspec validate --strict`, then the dry-run archive check from CLAUDE.md (scenario count before vs after), then archive for real.
+
+## 3. Verification
+
+- [x] 3.1 `pnpm build`, `pnpm typecheck`, `pnpm lint`, `pnpm --filter @taskless/cli test` all pass.
diff --git a/openspec/specs/cli-detect/spec.md b/openspec/specs/cli-detect/spec.md
index 973be667..48a07c44 100644
--- a/openspec/specs/cli-detect/spec.md
+++ b/openspec/specs/cli-detect/spec.md
@@ -36,7 +36,8 @@ inferred.
 
 - **WHEN** the working directory contains a recognized linter config (for
   example `.eslintrc*`, `eslint.config.js`, `ruff.toml`, a `[tool.ruff]` block in
-  `pyproject.toml`, `.rubocop.yml`, `biome.json`, or `stylelint` config)
+  `pyproject.toml`, `.rubocop.yml`, `biome.json`, `.oxlintrc.json`, or
+  `stylelint` config)
 - **THEN** `detect --json` SHALL report each configured linter it found
 
 #### Scenario: Languages are reported
@@ -52,6 +53,14 @@ inferred.
 - **THEN** `detect --json` SHALL NOT report that linter from the mismatched
   manifest
 
+#### Scenario: oxlint is detected from its config or its dependency
+
+- **WHEN** the working directory contains one of the config files oxlint
+  discovers on its own (`.oxlintrc.json`, `.oxlintrc.jsonc`, `oxlint.config.ts`,
+  `oxlint.config.mts`), or names `oxlint` as a dependency in `package.json`
+- **THEN** `detect --json` SHALL report `oxlint` as a JavaScript/TypeScript linter
+- **AND** a repository configured only for eslint SHALL NOT report `oxlint`
+
 #### Scenario: Configs in monorepo sub-packages are detected
 
 - **WHEN** a linter config or language manifest lives in a sub-package rather
diff --git a/packages/cli/src/detect/scan.ts b/packages/cli/src/detect/scan.ts
index 1de74565..5c0d1a26 100644
--- a/packages/cli/src/detect/scan.ts
+++ b/packages/cli/src/detect/scan.ts
@@ -120,6 +120,20 @@ const LINTER_SIGNALS: readonly LinterSignal[] = [
     configFiles: ["biome.json", "biome.jsonc"],
     deps: ["@biomejs/biome"],
   },
+  {
+    name: "oxlint",
+    languages: ["JavaScript", "TypeScript"],
+    // The four names oxlint discovers on its own (oxc.rs, "Configuration").
+    // `oxlint.config.{js,mjs,cjs}` are accepted only via `-c`, never found by
+    // the walk, so listing them would be dead weight in the sweep.
+    configFiles: [
+      ".oxlintrc.json",
+      ".oxlintrc.jsonc",
+      "oxlint.config.ts",
+      "oxlint.config.mts",
+    ],
+    deps: ["oxlint"],
+  },
   {
     name: "stylelint",
     languages: ["JavaScript", "TypeScript"],
diff --git a/packages/cli/test/detect.test.ts b/packages/cli/test/detect.test.ts
index 7942e103..0ec72755 100644
--- a/packages/cli/test/detect.test.ts
+++ b/packages/cli/test/detect.test.ts
@@ -127,6 +127,35 @@ describe("taskless detect", () => {
     expect(linterNames(result)).toContain("biome");
   });
 
+  it("detects oxlint from .oxlintrc.json", async () => {
+    await writeFile(join(cwd, ".oxlintrc.json"), "{}", "utf8");
+    const result = await detect(cwd);
+    expect(linterNames(result)).toContain("oxlint");
+    expect(linterNames(result)).not.toContain("eslint");
+  });
+
+  it("detects oxlint from a package.json devDependency", async () => {
+    await writeFile(
+      join(cwd, "package.json"),
+      JSON.stringify({ devDependencies: { oxlint: "^1.0.0" } }),
+      "utf8"
+    );
+    const result = await detect(cwd);
+    expect(linterNames(result)).toContain("oxlint");
+  });
+
+  it("does not report oxlint for an eslint-only repo", async () => {
+    await writeFile(join(cwd, ".eslintrc.json"), "{}", "utf8");
+    await writeFile(
+      join(cwd, "package.json"),
+      JSON.stringify({ devDependencies: { eslint: "^9.0.0" } }),
+      "utf8"
+    );
+    const result = await detect(cwd);
+    expect(linterNames(result)).toContain("eslint");
+    expect(linterNames(result)).not.toContain("oxlint");
+  });
+
   it("detects stylelint from a package.json devDependency", async () => {
     await writeFile(
       join(cwd, "package.json"),