diff --git a/.windsurf/rules/specify-rules.md b/.windsurf/rules/specify-rules.md
new file mode 100644
index 0000000..3e858be
--- /dev/null
+++ b/.windsurf/rules/specify-rules.md
@@ -0,0 +1,34 @@
+# diff Development Guidelines
+
+Auto-generated from all feature plans. Last updated: 2026-02-07
+
+## Active Technologies
+
+- N/A (client-side only, no persistence) (001-text-diff)
+
+- TypeScript 5.9.3 (strict mode) + React 19.2.4, `diff` (npm — to be added as runtime dependency) (001-text-diff)
+
+## Project Structure
+
+```text
+backend/
+frontend/
+tests/
+```
+
+## Commands
+
+npm test && npm run lint
+
+## Code Style
+
+TypeScript 5.9.3 (strict mode): Follow standard conventions
+
+## Recent Changes
+
+- 001-text-diff: Added TypeScript 5.9.3 (strict mode) + React 19.2.4, `diff` (npm — to be added as runtime dependency)
+
+- 001-text-diff: Added TypeScript 5.9.3 (strict mode) + React 19.2.4, `diff` (npm — to be added as runtime dependency)
+
+
+
diff --git a/AGENTS.md b/AGENTS.md
index d39c9bb..d6d781e 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -44,9 +44,8 @@ You're an expert engineer for this React app.
### Testing
-- **Watch mode:** `npm test` (run Vitest tests in watch mode with file watching)
- **Coverage:** `npm run test:ci` (run tests with coverage report, requires 100% coverage)
-- **Single test file:** `npm test -- --run path/to/test.test.tsx` (run specific test file)
+- **Single test file:** `npm test -- path/to/test.test.tsx` (run specific test file)
- **Single test with coverage:** `npm run test:ci -- path/to/test.test.tsx`
## Code Style Guidelines
@@ -115,7 +114,7 @@ import type { User } from './types';
- **Mock external dependencies** - mock API calls, browser APIs, etc.
- **Descriptive test names** - should clearly state what is being tested
- **Vitest globals** - use `vi.fn()`, `vi.mock()`, `vi.clearAllMocks()`
-- **Test setup** - global test environment configured in `vitest.config.mts` with `globals: true`
+- **Test setup** - global test environment configured in `vite.config.mts` with `globals: true`
### Code Quality Rules
diff --git a/README.md b/README.md
index 337cb15..701e041 100644
--- a/README.md
+++ b/README.md
@@ -1,11 +1,11 @@
-# diff
+# 📝 Diff
[](https://github.com/remarkablemark/diff/actions/workflows/build.yml)
[](https://github.com/remarkablemark/diff/actions/workflows/test.yml)
-📝 Check the diff between 2 files:
+Compare the [diff](https://wikipedia.org/wiki/Diff#Use) between 2 texts:
-- [diff](https://remarkablemark.org/diff/)
+- [Website](https://remarkablemark.org/diff/)
## Install
diff --git a/index.html b/index.html
index 303e198..9f0a37c 100644
--- a/index.html
+++ b/index.html
@@ -2,13 +2,19 @@
-
+
- diff
+
+ Diff
-
+
diff --git a/package-lock.json b/package-lock.json
index 51aa4c4..438fb34 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -8,6 +8,7 @@
"name": "diff",
"version": "1.0.0-alpha",
"dependencies": {
+ "diff": "8.0.3",
"react": "19.2.4",
"react-dom": "19.2.4"
},
@@ -5265,10 +5266,9 @@
}
},
"node_modules/diff": {
- "version": "4.0.4",
- "resolved": "https://registry.npmjs.org/diff/-/diff-4.0.4.tgz",
- "integrity": "sha512-X07nttJQkwkfKfvTPG/KSnE2OMdcUCao6+eXF3wmnIQRn2aPAHH3VxDbDOdegkd6JbPsXqShpvEOHfAT+nCNwQ==",
- "dev": true,
+ "version": "8.0.3",
+ "resolved": "https://registry.npmjs.org/diff/-/diff-8.0.3.tgz",
+ "integrity": "sha512-qejHi7bcSD4hQAZE0tNAawRK1ZtafHDmMTMkrrIGgSLl7hTnQHmKCeB45xAcbfTqK2zowkM3j3bHt/4b/ARbYQ==",
"license": "BSD-3-Clause",
"engines": {
"node": ">=0.3.1"
@@ -8738,6 +8738,16 @@
}
}
},
+ "node_modules/ts-node/node_modules/diff": {
+ "version": "4.0.4",
+ "resolved": "https://registry.npmjs.org/diff/-/diff-4.0.4.tgz",
+ "integrity": "sha512-X07nttJQkwkfKfvTPG/KSnE2OMdcUCao6+eXF3wmnIQRn2aPAHH3VxDbDOdegkd6JbPsXqShpvEOHfAT+nCNwQ==",
+ "dev": true,
+ "license": "BSD-3-Clause",
+ "engines": {
+ "node": ">=0.3.1"
+ }
+ },
"node_modules/ts-pattern": {
"version": "5.9.0",
"resolved": "https://registry.npmjs.org/ts-pattern/-/ts-pattern-5.9.0.tgz",
diff --git a/package.json b/package.json
index f7d9ff3..b33aec3 100644
--- a/package.json
+++ b/package.json
@@ -11,10 +11,12 @@
"prepare": "husky",
"preview": "vite preview",
"start": "vite --open",
- "test": "vitest",
- "test:ci": "CI=true npm test -- --color --coverage --run"
+ "test": "vitest run",
+ "test:ci": "CI=true npm test -- --color --coverage",
+ "test:watch": "vitest"
},
"dependencies": {
+ "diff": "8.0.3",
"react": "19.2.4",
"react-dom": "19.2.4"
},
diff --git a/public/react.svg b/public/react.svg
deleted file mode 100644
index 8e0e0f1..0000000
--- a/public/react.svg
+++ /dev/null
@@ -1 +0,0 @@
-
diff --git a/public/tailwind.svg b/public/tailwind.svg
deleted file mode 100644
index 6a9ab49..0000000
--- a/public/tailwind.svg
+++ /dev/null
@@ -1 +0,0 @@
-
\ No newline at end of file
diff --git a/public/vite.svg b/public/vite.svg
deleted file mode 100644
index e7b8dfb..0000000
--- a/public/vite.svg
+++ /dev/null
@@ -1 +0,0 @@
-
\ No newline at end of file
diff --git a/specs/001-text-diff/checklists/requirements.md b/specs/001-text-diff/checklists/requirements.md
new file mode 100644
index 0000000..be09a5f
--- /dev/null
+++ b/specs/001-text-diff/checklists/requirements.md
@@ -0,0 +1,44 @@
+# Specification Quality Checklist: Diff
+
+**Purpose**: Validate specification completeness and quality before proceeding to planning
+**Created**: 2026-02-07
+**Feature**: [spec.md](../spec.md)
+
+## Content Quality
+
+- [x] No implementation details (languages, frameworks, APIs)
+- [x] Focused on user value and business needs
+- [x] Written for non-technical stakeholders
+- [x] All mandatory sections completed
+
+## Requirement Completeness
+
+- [x] No [NEEDS CLARIFICATION] markers remain
+- [x] Requirements are testable and unambiguous
+- [x] Success criteria are measurable
+- [x] Success criteria are technology-agnostic (no implementation details)
+- [x] All acceptance scenarios are defined
+- [x] Edge cases are identified
+- [x] Scope is clearly bounded
+- [x] Dependencies and assumptions identified
+
+## Feature Readiness
+
+- [x] All functional requirements have clear acceptance criteria
+- [x] User scenarios cover primary flows
+- [x] Feature meets measurable outcomes defined in Success Criteria
+- [x] No implementation details leak into specification
+
+## Notes
+
+- All items pass validation. Spec is ready for `/speckit.plan`.
+- Clarification session 2026-02-07 resolved 8 questions:
+ 1. Diff library: `diff` (`npm: diff`)
+ 2. Display format: Both unified inline and side-by-side views with toggle
+ 3. Diff granularity: Word-level
+ 4. Text input component: Plain `