chore: migrate toolchain to oxc + TypeScript 7 + vite 8

.agent/self-learning/INDEX.md

@@ -11,4 +11,5 @@ If a `Use when ...` condition matches the current task, read the full lesson fil
 - [update-docs-with-new-cases](lessons/2026-05-19-update-docs-with-new-cases.md) — Use when adding a new use case, capability, or behavior change to tanstack/ai — public docs that cover the surface need updating in the same PR
 - [authoring-kiira-doc-snippets](lessons/2026-06-23-authoring-kiira-doc-snippets.md) — Use when writing or fixing TS/TSX code samples in docs/\*\* so they type-check under kiira AND read as idiomatic, type-safe examples (no declare const / ambient magic / group-rename / input:any / as casts)
 - [kiira-ci-setup](lessons/2026-06-23-kiira-ci-setup.md) — Use when running, configuring, or debugging kiira in tanstack/ai — config, CI wiring, source resolution (ai-angular exclusion), reading errors with --verbose
+
 <!-- LESSONS:END -->

.oxfmtrc.json

@@ -0,0 +1,22 @@
+{
+  "$schema": "./node_modules/oxfmt/configuration_schema.json",
+  "semi": false,
+  "singleQuote": true,
+  "trailingComma": "all",
+  "printWidth": 80,
+  "sortPackageJson": false,
+  "svelte": {},
+  "ignorePatterns": [
+    "**/.nx/",
+    "**/.nx/cache",
+    "**/.svelte-kit",
+    "**/build",
+    "**/coverage",
+    "**/dist",
+    "**/docs",
+    "packages/ai-fal/src/image/generated/",
+    "pnpm-lock.yaml",
+    ".angular",
+    ".github"
+  ]
+}

.oxlintrc.json

@@ -0,0 +1,251 @@
+{
+  "$schema": "./node_modules/oxlint/configuration_schema.json",
+  "plugins": [],
+  "jsPlugins": [
+    "eslint-plugin-unused-imports",
+    { "name": "eslint-js", "specifier": "oxlint-plugin-eslint" }
+  ],
+  "categories": {
+    "correctness": "off"
+  },
+  "env": {
+    "builtin": true
+  },
+  "ignorePatterns": [
+    "**/.nx/**",
+    "**/.svelte-kit/**",
+    "**/build/**",
+    "**/coverage/**",
+    "**/dist/**",
+    "**/snap/**",
+    "**/vite.config.*.timestamp-*.*"
+  ],
+  "rules": {
+    "unused-imports/no-unused-imports": "warn"
+  },
+  "overrides": [
+    {
+      "files": ["**/*.{js,ts,tsx}"],
+      "rules": {
+        "for-direction": "error",
+        "no-async-promise-executor": "error",
+        "no-case-declarations": "error",
+        "no-class-assign": "error",
+        "no-compare-neg-zero": "error",
+        "no-cond-assign": "error",
+        "no-constant-binary-expression": "error",
+        "no-constant-condition": "error",
+        "no-control-regex": "error",
+        "no-debugger": "error",
+        "no-delete-var": "error",
+        "no-dupe-else-if": "error",
+        "no-duplicate-case": "error",
+        "no-empty-character-class": "error",
+        "no-empty-pattern": "error",
+        "no-empty-static-block": "error",
+        "no-ex-assign": "error",
+        "no-extra-boolean-cast": "error",
+        "no-fallthrough": "error",
+        "no-global-assign": "error",
+        "no-invalid-regexp": "error",
+        "no-irregular-whitespace": "error",
+        "no-loss-of-precision": "error",
+        "no-misleading-character-class": "error",
+        "no-nonoctal-decimal-escape": "error",
+        "no-regex-spaces": "error",
+        "no-self-assign": "error",
+        "no-shadow": "warn",
+        "no-shadow-restricted-names": "error",
+        "no-sparse-arrays": "error",
+        "no-unsafe-finally": "error",
+        "no-unsafe-optional-chaining": "error",
+        "no-unused-labels": "error",
+        "no-unused-private-class-members": "error",
+        "no-useless-backreference": "error",
+        "no-useless-catch": "error",
+        "no-useless-escape": "error",
+        "no-var": "error",
+        "no-with": "error",
+        "prefer-const": "error",
+        "require-yield": "error",
+        "use-isnan": "error",
+        "valid-typeof": "error",
+        "import/consistent-type-specifier-style": ["error", "prefer-top-level"],
+        "import/first": "error",
+        "import/newline-after-import": "error",
+        "import/no-commonjs": "error",
+        "import/no-duplicates": "error",
+        "@stylistic/spaced-comment": "error",
+        "typescript/array-type": [
+          "error",
+          {
+            "default": "generic",
+            "readonly": "generic"
+          }
+        ],
+        "typescript/ban-ts-comment": [
+          "error",
+          {
+            "ts-expect-error": false,
+            "ts-ignore": "allow-with-description"
+          }
+        ],
+        "typescript/consistent-type-imports": [
+          "error",
+          {
+            "prefer": "type-imports"
+          }
+        ],
+        "typescript/method-signature-style": ["error", "property"],
+        "typescript/no-duplicate-enum-values": "error",
+        "typescript/no-extra-non-null-assertion": "error",
+        "typescript/no-inferrable-types": [
+          "error",
+          {
+            "ignoreParameters": true
+          }
+        ],
+        "typescript/no-misused-new": "error",
+        "typescript/no-namespace": "error",
+        "typescript/no-non-null-asserted-optional-chain": "error",
+        "typescript/no-unsafe-function-type": "error",
+        "typescript/no-wrapper-object-types": "error",
+        "typescript/prefer-as-const": "error",
+        "typescript/prefer-for-of": "warn",
+        "typescript/triple-slash-reference": "error"
+      },
+      "jsPlugins": ["@stylistic/eslint-plugin"],
+      "env": {
+        "es2020": true,
+        "browser": true
+      },
+      "plugins": ["typescript", "import"]
+    },
+    {
+      "files": ["**/*.vue"],
+      "rules": {
+        "for-direction": "error",
+        "no-async-promise-executor": "error",
+        "no-case-declarations": "error",
+        "no-class-assign": "error",
+        "no-compare-neg-zero": "error",
+        "no-cond-assign": "error",
+        "no-constant-binary-expression": "error",
+        "no-constant-condition": "error",
+        "no-control-regex": "error",
+        "no-debugger": "error",
+        "no-delete-var": "error",
+        "no-dupe-else-if": "error",
+        "no-duplicate-case": "error",
+        "no-empty-character-class": "error",
+        "no-empty-pattern": "error",
+        "no-empty-static-block": "error",
+        "no-ex-assign": "error",
+        "no-extra-boolean-cast": "error",
+        "no-fallthrough": "error",
+        "no-global-assign": "error",
+        "no-invalid-regexp": "error",
+        "no-irregular-whitespace": "error",
+        "no-loss-of-precision": "error",
+        "no-misleading-character-class": "error",
+        "no-nonoctal-decimal-escape": "error",
+        "no-regex-spaces": "error",
+        "no-self-assign": "error",
+        "no-shadow": "warn",
+        "no-shadow-restricted-names": "error",
+        "no-sparse-arrays": "error",
+        "no-unsafe-finally": "error",
+        "no-unsafe-optional-chaining": "error",
+        "no-unused-labels": "error",
+        "no-unused-private-class-members": "error",
+        "no-useless-backreference": "error",
+        "no-useless-catch": "error",
+        "no-useless-escape": "error",
+        "no-var": "error",
+        "no-with": "error",
+        "prefer-const": "error",
+        "require-yield": "error",
+        "use-isnan": "error",
+        "valid-typeof": "error",
+        "import/consistent-type-specifier-style": ["error", "prefer-top-level"],
+        "import/first": "error",
+        "import/newline-after-import": "error",
+        "import/no-commonjs": "error",
+        "import/no-duplicates": "error",
+        "@stylistic/spaced-comment": "error",
+        "typescript/array-type": [
+          "error",
+          {
+            "default": "generic",
+            "readonly": "generic"
+          }
+        ],
+        "typescript/ban-ts-comment": [
+          "error",
+          {
+            "ts-expect-error": false,
+            "ts-ignore": "allow-with-description"
+          }
+        ],
+        "typescript/consistent-type-imports": [
+          "error",
+          {
+            "prefer": "type-imports"
+          }
+        ],
+        "typescript/method-signature-style": ["error", "property"],
+        "typescript/no-duplicate-enum-values": "error",
+        "typescript/no-extra-non-null-assertion": "error",
+        "typescript/no-inferrable-types": [
+          "error",
+          {
+            "ignoreParameters": true
+          }
+        ],
+        "typescript/no-misused-new": "error",
+        "typescript/no-namespace": "error",
+        "typescript/no-non-null-asserted-optional-chain": "error",
+        "typescript/no-unsafe-function-type": "error",
+        "typescript/no-wrapper-object-types": "error",
+        "typescript/prefer-as-const": "error",
+        "typescript/prefer-for-of": "warn",
+        "typescript/triple-slash-reference": "error"
+      },
+      "jsPlugins": ["@stylistic/eslint-plugin"],
+      "plugins": ["typescript", "import"],
+      "env": {
+        "browser": true
+      }
+    },
+    {
+      "files": ["packages/*/src/**/*.{ts,tsx}"],
+      "rules": {
+        "typescript/no-non-null-assertion": "error",
+        "typescript/no-explicit-any": "warn",
+        "typescript/no-floating-promises": "error",
+        "typescript/no-misused-promises": "error",
+        "typescript/await-thenable": "error",
+        "typescript/switch-exhaustiveness-check": "error",
+        "typescript/consistent-type-exports": "error",
+        "typescript/prefer-readonly": "error",
+        "typescript/ban-ts-comment": [
+          "error",
+          {
+            "ts-expect-error": "allow-with-description",
+            "ts-ignore": false,
+            "ts-nocheck": true,
+            "ts-check": false
+          }
+        ],
+        "eslint-js/no-restricted-syntax": [
+          "error",
+          {
+            "selector": "TSAsExpression > TSAsExpression[typeAnnotation.type='TSUnknownKeyword']",
+            "message": "Avoid `as unknown as <Type>` — it bypasses TS's structural overlap check. Prefer plain `as <Type>`, fix the root cause, or opt out with `// oxlint-disable-next-line eslint-js/no-restricted-syntax -- <reason>`."
+          }
+        ]
+      },
+      "plugins": ["typescript"]
+    }
+  ]
+}

.vscode/extensions.json

@@ -1,7 +1,7 @@
 {
   "recommendations": [
     "dbaeumer.vscode-eslint",
-    "esbenp.prettier-vscode",
+    "oxc.oxc-vscode",
     "vitest.explorer",
     "nrwl.angular-console",
     "svelte.svelte-vscode",

CLAUDE.md

@@ -10,10 +10,16 @@ TanStack AI is a type-safe, provider-agnostic AI SDK for building AI-powered app
 
 - **Package Manager**: pnpm@10.17.0 (required)
 - **Build System**: Nx for task orchestration and caching
-- **TypeScript**: 5.9.3
+- **TypeScript**: 7.0.2 (native Go compiler). Framework build/typecheck tools
+  that still need the pre-7 JS Compiler API (svelte-package, svelte-check,
+  vue-tsc, kiira, knip) run against the `@typescript/typescript6` (6.0.2) shim
+  via `pnpm-workspace.yaml` packageExtensions; the framework packages
+  themselves stay pinned to 5.9.3. See that file's comments.
 - **Testing**: Vitest for unit tests
-- **Linting**: ESLint with custom TanStack config
-- **Formatting**: Prettier
+- **Linting**: oxlint (incl. type-aware rules via `oxlint-tsgolint`); a few
+  ESLint-compat rules run through oxlint's JS-plugin layer
+  (`oxlint-plugin-eslint`, `eslint-plugin-unused-imports`, `@stylistic`)
+- **Formatting**: oxfmt
 
 Run `pnpm install` before starting any task and again after every merge with
 `main`.
@@ -32,7 +38,7 @@ pnpm test:pr
 # Run specific test suites
 pnpm test:lib              # Run unit tests for affected packages
 pnpm test:lib:dev          # Watch mode for unit tests
-pnpm test:eslint           # Lint affected packages
+pnpm test:oxlint           # Lint affected packages (oxlint, incl. type-aware)
 pnpm test:types            # Type check affected packages
 pnpm test:build            # Verify build artifacts with publint
 pnpm test:coverage         # Generate coverage reports
@@ -53,7 +59,7 @@ cd packages/ai
 pnpm test:lib              # Run tests for this package
 pnpm test:lib:dev          # Watch mode
 pnpm test:types            # Type check
-pnpm test:eslint           # Lint
+pnpm test:oxlint           # Lint (oxlint)
 ```
 
 ### Building
@@ -73,7 +79,7 @@ pnpm dev  # alias for watch
 ### Code Quality
 
 ```bash
-pnpm format                # Format all files with Prettier
+pnpm format                # Format all files with oxfmt
 ```
 
 ### Changesets (Release Management)
@@ -214,7 +220,7 @@ Each framework integration uses the headless `ai-client` under the hood.
 4. Run tests: `pnpm test:lib` (or package-specific tests)
 5. Run E2E tests: `pnpm --filter @tanstack/ai-e2e test:e2e`
 6. Run type checks: `pnpm test:types`
-7. Run linter: `pnpm test:eslint`
+7. Run linter: `pnpm test:oxlint`
 8. Format code: `pnpm format`
 9. Verify build: `pnpm test:build` or `pnpm build`
 
@@ -230,14 +236,14 @@ The single canonical command is:
 pnpm test:pr
 ```
 
-This runs the exact target set the `PR` workflow runs in CI: `nx affected --targets=test:sherif,test:knip,test:docs,test:kiira,test:eslint,test:lib,test:types,test:build,build`. There is **no** `--exclude=examples/**,testing/**` carve-out — the example apps and `testing/` packages are included, so Nx runs whatever of these targets they define (in practice `build` and `test:types`). Including them means `test:types` is checked at the call sites where the library is actually consumed, catching call-site type regressions that only manifest there (see issue #820). To type-check just the example apps + `testing/` packages locally, run `nx run-many --targets=test:types --projects=examples/**,testing/**`.
+This runs the exact target set the `PR` workflow runs in CI: `nx affected --targets=test:sherif,test:knip,test:docs,test:kiira,test:oxlint,test:lib,test:types,test:build,build`. There is **no** `--exclude=examples/**,testing/**` carve-out — the example apps and `testing/` packages are included, so Nx runs whatever of these targets they define (in practice `build` and `test:types`). Including them means `test:types` is checked at the call sites where the library is actually consumed, catching call-site type regressions that only manifest there (see issue #820). To type-check just the example apps + `testing/` packages locally, run `nx run-many --targets=test:types --projects=examples/**,testing/**`.
 
 If you can't run `test:pr` (e.g. it's too slow on your machine), at minimum run each of these and confirm they're green before pushing:
 
 - `pnpm test:sherif` — workspace consistency
 - `pnpm test:knip` — unused dependencies
 - `pnpm test:docs` — doc link verification
-- `pnpm test:eslint` — lint
+- `pnpm test:oxlint` — lint (oxlint, incl. type-aware)
 - `pnpm test:types` — typecheck (packages)
 - `nx run-many --targets=test:types --projects=examples/**,testing/**` — typecheck the example apps + `testing/` packages
 - `pnpm test:lib` — unit tests

codemods/package.json

@@ -17,6 +17,6 @@
     "jscodeshift": "^17.1.1",
     "prettier": "^3.7.4",
     "typescript": "5.9.3",
-    "vitest": "^4.0.14"
+    "vitest": "^4.1.10"
   }
 }