feat(setup/project-init): initialize TypeScript ESM project skeleton

- package.json with @alkdev/taskgraph, ESM primary, CJS compat exports
- tsconfig.json targeting Node 18+, strict mode, declaration output
- All production deps: graphology suite, @alkdev/typebox, yaml
- Dev deps: typescript, vitest, @types/node
- src/ skeleton: schema, graph, analysis, frontmatter, error modules
- test/ directory with 5 placeholder test files
- .gitignore and vitest.config.ts

.gitignore

@@ -0,0 +1,23 @@
+# Dependencies
+node_modules/
+
+# Build output
+dist/
+
+# Source maps
+*.js.map
+
+# Environment
+.env
+.env.*
+
+# IDE
+.vscode/
+.idea/
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Coverage
+coverage/

package.json

@@ -0,0 +1,56 @@
+{
+  "name": "@alkdev/taskgraph",
+  "version": "0.0.1",
+  "description": "Task graph library — directed acyclic graph analysis, risk scoring, and YAML frontmatter for task management",
+  "type": "module",
+  "main": "./dist/index.cjs",
+  "module": "./dist/index.js",
+  "types": "./dist/index.d.ts",
+  "exports": {
+    ".": {
+      "import": {
+        "types": "./dist/index.d.ts",
+        "default": "./dist/index.js"
+      },
+      "require": {
+        "types": "./dist/index.d.cts",
+        "default": "./dist/index.cjs"
+      }
+    }
+  },
+  "files": [
+    "dist"
+  ],
+  "scripts": {
+    "build": "tsc",
+    "test": "vitest run",
+    "test:watch": "vitest",
+    "lint": "tsc --noEmit",
+    "prepublishOnly": "npm run build"
+  },
+  "keywords": [
+    "taskgraph",
+    "dag",
+    "critical-path",
+    "risk-analysis",
+    "graphology"
+  ],
+  "license": "MIT",
+  "dependencies": {
+    "graphology": "^0.26.0",
+    "graphology-dag": "^0.4.1",
+    "graphology-metrics": "^2.4.0",
+    "graphology-components": "^1.5.4",
+    "graphology-operators": "^1.6.1",
+    "@alkdev/typebox": "^0.34.49",
+    "yaml": "^2.8.3"
+  },
+  "devDependencies": {
+    "typescript": "^5.7.0",
+    "vitest": "^3.1.0",
+    "@types/node": "^22.0.0"
+  },
+  "engines": {
+    "node": ">=18.0.0"
+  }
+}

src/analysis/bottleneck.ts

@@ -0,0 +1 @@
+// bottlenecks (graphology betweenness)

src/analysis/cost-benefit.ts

@@ -0,0 +1 @@
+// calculateTaskEv, workflowCost, computeEffectiveP

src/analysis/critical-path.ts

@@ -0,0 +1 @@
+// criticalPath, weightedCriticalPath

src/analysis/decompose.ts

@@ -0,0 +1 @@
+// shouldDecomposeTask

src/analysis/defaults.ts

@@ -0,0 +1 @@
+// resolveDefaults, enum numeric methods

src/analysis/index.ts

@@ -0,0 +1,8 @@
+// Analysis submodule — re-exports
+
+export * from './critical-path.js';
+export * from './bottleneck.js';
+export * from './risk.js';
+export * from './cost-benefit.js';
+export * from './decompose.js';
+export * from './defaults.js';

src/analysis/risk.ts

@@ -0,0 +1 @@
+// riskPath, riskDistribution

src/error/index.ts

@@ -0,0 +1,44 @@
+// Error classes — TaskgraphError, TaskNotFoundError, CircularDependencyError,
+// InvalidInputError, DuplicateNodeError, DuplicateEdgeError
+
+export class TaskgraphError extends Error {
+  constructor(message: string) {
+    super(message);
+    this.name = 'TaskgraphError';
+  }
+}
+
+export class TaskNotFoundError extends TaskgraphError {
+  constructor(taskId: string) {
+    super(`Task not found: ${taskId}`);
+    this.name = 'TaskNotFoundError';
+  }
+}
+
+export class CircularDependencyError extends TaskgraphError {
+  constructor(cycle: string[]) {
+    super(`Circular dependency detected: ${cycle.join(' → ')}`);
+    this.name = 'CircularDependencyError';
+  }
+}
+
+export class InvalidInputError extends TaskgraphError {
+  constructor(message: string) {
+    super(message);
+    this.name = 'InvalidInputError';
+  }
+}
+
+export class DuplicateNodeError extends TaskgraphError {
+  constructor(nodeId: string) {
+    super(`Duplicate node: ${nodeId}`);
+    this.name = 'DuplicateNodeError';
+  }
+}
+
+export class DuplicateEdgeError extends TaskgraphError {
+  constructor(source: string, target: string) {
+    super(`Duplicate edge: ${source} → ${target}`);
+    this.name = 'DuplicateEdgeError';
+  }
+}

src/frontmatter/index.ts

@@ -0,0 +1,4 @@
+// Frontmatter submodule — parse and serialize
+
+export { parseFrontmatter, parseTaskFile, parseTaskDirectory } from './parse.js';
+export { serializeFrontmatter } from './serialize.js';

src/frontmatter/parse.ts

@@ -0,0 +1,16 @@
+// YAML/frontmatter parsing + typebox validation
+
+export function parseFrontmatter(_input: string): unknown {
+  // Stub — implementation pending
+  return {};
+}
+
+export function parseTaskFile(_input: string): unknown {
+  // Stub — implementation pending
+  return {};
+}
+
+export function parseTaskDirectory(_dir: string): unknown[] {
+  // Stub — implementation pending
+  return [];
+}

src/frontmatter/serialize.ts

@@ -0,0 +1,6 @@
+// TaskInput → markdown with frontmatter
+
+export function serializeFrontmatter(_input: unknown): string {
+  // Stub — implementation pending
+  return '';
+}

src/graph/construction.ts

@@ -0,0 +1,5 @@
+// TaskGraph class construction — fromTasks, fromRecords, fromJSON, incremental building
+
+export class TaskGraph {
+  // Stub — implementation pending
+}

src/graph/index.ts

@@ -0,0 +1,5 @@
+// Graph submodule — TaskGraph class and operations
+
+export { TaskGraph } from './construction.js';
+export * from './queries.js';
+export * from './mutation.js';

src/graph/mutation.ts

@@ -0,0 +1 @@
+// Graph mutations — removeTask, removeDependency, updateTask, updateEdgeAttributes

src/graph/queries.ts

@@ -0,0 +1 @@
+// Graph queries — hasCycles, findCycles, topologicalOrder, dependencies, dependents

src/index.ts

@@ -0,0 +1,8 @@
+// @alkdev/taskgraph — Public API surface
+// Re-exports from all submodules
+
+export * from './schema/index.js';
+export * from './graph/index.js';
+export * from './analysis/index.js';
+export * from './frontmatter/index.js';
+export * from './error/index.js';

src/schema/enums.ts

@@ -0,0 +1 @@
+// Enum definitions: TaskScope, TaskRisk, TaskImpact, TaskLevel, TaskStatus, TaskPriority

src/schema/graph.ts

@@ -0,0 +1 @@
+// TaskGraphNodeAttributes, TaskGraphEdgeAttributes, SerializedGraph schemas

src/schema/index.ts

@@ -0,0 +1,6 @@
+// Schema submodule — re-exports
+
+export * from './enums.js';
+export * from './task.js';
+export * from './graph.js';
+export * from './results.js';

src/schema/results.ts

@@ -0,0 +1 @@
+// RiskPathResult, DecomposeResult, WorkflowCostResult, RiskDistributionResult schemas

src/schema/task.ts

@@ -0,0 +1 @@
+// TaskInput, DependencyEdge schemas

tasks/implementation/setup/project-init.md

@@ -1,7 +1,7 @@
 ---
 id: setup/project-init
 name: Initialize project with package.json, tsconfig, and build tooling
-status: pending
+status: completed
 depends_on: []
 scope: moderate
 risk: low
@@ -22,21 +22,21 @@ Per [build-distribution.md](../../../docs/architecture/build-distribution.md):
 
 ## Acceptance Criteria
 
-- [ ] `package.json` exists with name `@alkdev/taskgraph`, ESM primary (`"type": "module"`), CJS compat config
-- [ ] All production dependencies listed per [build-distribution.md](../../../docs/architecture/build-distribution.md) dependencies table
-- [ ] Dev dependencies include: `typescript`, `vitest` (or agreed test runner), `@types/node`
-- [ ] `tsconfig.json` configured for Node 18+ target, ESM module resolution, strict mode, declaration output
-- [ ] `.gitignore` covers `node_modules/`, `dist/`, `*.js.map`, `.env`
-- [ ] `src/` directory skeleton created per [build-distribution.md](../../../docs/architecture/build-distribution.md) project structure:
+- [x] `package.json` exists with name `@alkdev/taskgraph`, ESM primary (`"type": "module"`), CJS compat config
+- [x] All production dependencies listed per [build-distribution.md](../../../docs/architecture/build-distribution.md) dependencies table
+- [x] Dev dependencies include: `typescript`, `vitest` (or agreed test runner), `@types/node`
+- [x] `tsconfig.json` configured for Node 18+ target, ESM module resolution, strict mode, declaration output
+- [x] `.gitignore` covers `node_modules/`, `dist/`, `*.js.map`, `.env`
+- [x] `src/` directory skeleton created per [build-distribution.md](../../../docs/architecture/build-distribution.md) project structure:
   - `src/index.ts`
   - `src/schema/index.ts`, `src/schema/enums.ts`, `src/schema/task.ts`, `src/schema/graph.ts`, `src/schema/results.ts`
   - `src/graph/index.ts`, `src/graph/construction.ts`, `src/graph/queries.ts`, `src/graph/mutation.ts`
   - `src/analysis/index.ts`, `src/analysis/critical-path.ts`, `src/analysis/bottleneck.ts`, `src/analysis/risk.ts`, `src/analysis/cost-benefit.ts`, `src/analysis/decompose.ts`, `src/analysis/defaults.ts`
   - `src/frontmatter/index.ts`, `src/frontmatter/parse.ts`, `src/frontmatter/serialize.ts`
   - `src/error/index.ts`
-- [ ] `test/` directory created with placeholder test files per build-distribution spec
-- [ ] `npm install` succeeds without errors
-- [ ] `npx tsc --noEmit` succeeds (empty source files, but config is valid)
+- [x] `test/` directory created with placeholder test files per build-distribution spec
+- [x] `npm install` succeeds without errors
+- [x] `npx tsc --noEmit` succeeds (empty source files, but config is valid)
 
 ## References
 
@@ -44,8 +44,20 @@ Per [build-distribution.md](../../../docs/architecture/build-distribution.md):
 
 ## Notes
 
-> To be filled by implementation agent
+Dependency version adjustments from architecture spec:
+- `@alkdev/typebox`: ^0.2.0 → ^0.34.49 (only version available on npm)
+- `graphology`: ^0.25.4 → ^0.26.0 (latest on npm)
+- `graphology-dag`: ^0.4.2 → ^0.4.1 (latest on npm)
+- `graphology-metrics`: ^0.7.0 → ^2.4.0 (latest on npm)
+- `graphology-components`: ^0.3.1 → ^1.5.4 (latest on npm)
+- `graphology-operators`: ^0.5.2 → ^1.6.1 (latest on npm)
+- `yaml`: ^2.6.1 → ^2.8.3 (latest on npm)
 
 ## Summary
 
-> To be filled on completion
+Initialized the @alkdev/taskgraph TypeScript ESM project from scratch.
+- Created: package.json, tsconfig.json, vitest.config.ts, .gitignore
+- Created: src/ directory skeleton (20 source files across 5 modules: schema, graph, analysis, frontmatter, error)
+- Created: test/ directory (5 placeholder test files: graph, analysis, schema, frontmatter, cost-benefit)
+- Modified: tasks/implementation/setup/project-init.md (status → completed)
+- Tests: 5 passing, npm install ✓, tsc --noEmit ✓

test/analysis.test.ts

@@ -0,0 +1,7 @@
+import { describe, it, expect } from 'vitest';
+
+describe('Analysis', () => {
+  it('placeholder — critical path and risk analysis', () => {
+    expect(true).toBe(true);
+  });
+});

test/cost-benefit.test.ts

@@ -0,0 +1,7 @@
+import { describe, it, expect } from 'vitest';
+
+describe('Cost-Benefit', () => {
+  it('placeholder — EV and workflow cost calculations', () => {
+    expect(true).toBe(true);
+  });
+});

test/frontmatter.test.ts

@@ -0,0 +1,7 @@
+import { describe, it, expect } from 'vitest';
+
+describe('Frontmatter', () => {
+  it('placeholder — parse and serialize', () => {
+    expect(true).toBe(true);
+  });
+});

test/graph.test.ts

@@ -0,0 +1,7 @@
+import { describe, it, expect } from 'vitest';
+
+describe('TaskGraph', () => {
+  it('placeholder — construction and queries', () => {
+    expect(true).toBe(true);
+  });
+});

test/schema.test.ts

@@ -0,0 +1,7 @@
+import { describe, it, expect } from 'vitest';
+
+describe('Schema', () => {
+  it('placeholder — schema validation', () => {
+    expect(true).toBe(true);
+  });
+});

tsconfig.json

@@ -0,0 +1,26 @@
+{
+  "compilerOptions": {
+    "target": "ES2022",
+    "lib": ["ES2022"],
+    "module": "Node16",
+    "moduleResolution": "Node16",
+    "outDir": "./dist",
+    "rootDir": "./src",
+    "declaration": true,
+    "declarationMap": true,
+    "sourceMap": true,
+    "strict": true,
+    "noUncheckedIndexedAccess": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "noFallthroughCasesInSwitch": true,
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "forceConsistentCasingInFileNames": true,
+    "resolveJsonModule": true,
+    "isolatedModules": true,
+    "erasableSyntaxOnly": true
+  },
+  "include": ["src/**/*.ts"],
+  "exclude": ["node_modules", "dist", "test"]
+}

vitest.config.ts

@@ -0,0 +1,7 @@
+import { defineConfig } from 'vitest/config';
+
+export default defineConfig({
+  test: {
+    globals: true,
+  },
+});