diff --git a/.env.example b/.env.example
index cf455ff..cfc57a2 100644
--- a/.env.example
+++ b/.env.example
@@ -17,9 +17,12 @@ NODE_ENV=development
 # Public gitsheets data repo
 # ---------------------------------------------------------------------------
 
-# Absolute path (or relative from repo root) to the codeforphilly-data working tree.
-# Clone https://github.com/CodeForPhilly/codeforphilly-data-snapshot as a sibling:
-#   git clone https://github.com/CodeForPhilly/codeforphilly-data-snapshot ../codeforphilly-data
+# Path to the codeforphilly-data working tree. Relative paths are resolved
+# from the API workspace dir (`apps/api/`) — prefer absolute paths in dev.
+# Bootstrap a fresh dev data repo with the sheet configs the API needs:
+#   npm run -w apps/api script:setup-dev-data
+# (Uses this CFP_DATA_REPO_PATH; creates the directory + git repo + .gitsheets/<sheet>.toml.)
+# In production, point at a clone of https://github.com/CodeForPhilly/codeforphilly-data.
 CFP_DATA_REPO_PATH=../codeforphilly-data
 
 # Git remote URL to push public data commits to. Optional in dev; required in prod.
diff --git a/.gitignore b/.gitignore
index 63587d1..7ae6cb1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -18,6 +18,14 @@ build/
 # it ships in the code repo so contributors can load a fake-data baseline.
 private-storage/
 
+# Dev data repo created by `npm run -w apps/api script:setup-dev-data`.
+# Resolved relative to apps/api/ per .env.example's CFP_DATA_REPO_PATH default.
+apps/codeforphilly-data/
+codeforphilly-data/
+
+# Agent worktrees (claude-code background agents create these here).
+.claude/worktrees/
+
 # Editor / OS
 .DS_Store
 .vscode/*
diff --git a/apps/api/package.json b/apps/api/package.json
index 58ea467..2797f88 100644
--- a/apps/api/package.json
+++ b/apps/api/package.json
@@ -5,12 +5,13 @@
   "type": "module",
   "main": "dist/index.js",
   "scripts": {
-    "dev": "tsx watch src/index.ts",
+    "dev": "tsx watch --env-file=../../.env src/index.ts",
     "build": "tsc -p tsconfig.json",
     "start": "node dist/index.js",
     "type-check": "tsc -p tsconfig.json --noEmit",
     "test": "vitest run",
-    "script:scrub-data": "tsx scripts/scrub-data.ts"
+    "script:scrub-data": "tsx scripts/scrub-data.ts",
+    "script:setup-dev-data": "tsx scripts/setup-dev-data.ts"
   },
   "dependencies": {
     "@aws-sdk/client-s3": "^3.1048.0",
diff --git a/apps/api/scripts/setup-dev-data.ts b/apps/api/scripts/setup-dev-data.ts
new file mode 100644
index 0000000..6b4020d
--- /dev/null
+++ b/apps/api/scripts/setup-dev-data.ts
@@ -0,0 +1,105 @@
+// Seed a local development data repo with the minimal sheet configs the API
+// needs to boot. Run once after `cp .env.example .env`:
+//
+//   npm run -w apps/api script:setup-dev-data [-- <path>]
+//
+// `<path>` defaults to the value of `CFP_DATA_REPO_PATH` in the env, or
+// `../codeforphilly-data` if unset.
+//
+// What this does:
+//   1. Creates the directory if missing
+//   2. `git init -b main` if not already a repo
+//   3. Writes one `.gitsheets/<sheet>.toml` per declared sheet (minimal
+//      `[gitsheet]` block — root + a placeholder path template)
+//   4. Commits as `initial: dev data repo configs`
+//
+// The path templates here are dev-stub defaults, not authoritative. The real
+// templates are authored alongside the production data repo. For an empty
+// dev repo with no records, the path template doesn't matter at boot — only
+// the existence of `.gitsheets/<sheet>.toml` does.
+
+import { execFile } from 'node:child_process';
+import { existsSync } from 'node:fs';
+import { mkdir, writeFile } from 'node:fs/promises';
+import { resolve, join } from 'node:path';
+import { promisify } from 'node:util';
+
+const exec = promisify(execFile);
+
+const SHEET_CONFIGS: ReadonlyArray<{ name: string; root: string; path: string }> = [
+  { name: 'people', root: 'people', path: '${{ slug }}' },
+  { name: 'projects', root: 'projects', path: '${{ slug }}' },
+  { name: 'project-memberships', root: 'project-memberships', path: '${{ projectSlug }}/${{ personSlug }}' },
+  { name: 'project-updates', root: 'project-updates', path: '${{ projectSlug }}/${{ number }}' },
+  { name: 'project-buzz', root: 'project-buzz', path: '${{ projectSlug }}/${{ slug }}' },
+  { name: 'help-wanted-roles', root: 'help-wanted-roles', path: '${{ projectSlug }}/${{ slug }}' },
+  { name: 'help-wanted-interest', root: 'help-wanted-interest', path: '${{ roleId }}/${{ personId }}' },
+  { name: 'tags', root: 'tags', path: '${{ namespace }}/${{ slug }}' },
+  { name: 'tag-assignments', root: 'tag-assignments', path: '${{ taggableType }}/${{ taggableId }}/${{ tagId }}' },
+  { name: 'slug-history', root: 'slug-history', path: '${{ entityType }}/${{ slug }}' },
+  { name: 'revocations', root: 'revocations', path: '${{ jti }}' },
+];
+
+function configToml(root: string, path: string): string {
+  return `[gitsheet]\nroot = '${root}'\npath = '${path}'\n`;
+}
+
+async function main(): Promise<void> {
+  const argPath = process.argv[2];
+  const envPath = process.env['CFP_DATA_REPO_PATH'];
+  const targetPath = resolve(argPath ?? envPath ?? '../codeforphilly-data');
+
+  console.log(`[setup-dev-data] target: ${targetPath}`);
+
+  if (!existsSync(targetPath)) {
+    await mkdir(targetPath, { recursive: true });
+    console.log(`[setup-dev-data] created directory`);
+  }
+
+  const git = async (...args: string[]): Promise<string> => {
+    const { stdout } = await exec('git', args, { cwd: targetPath });
+    return stdout;
+  };
+
+  if (!existsSync(join(targetPath, '.git'))) {
+    await git('init', '-b', 'main');
+    await git('config', 'user.email', 'dev@local');
+    await git('config', 'user.name', 'Dev');
+    await git('commit', '--allow-empty', '-m', 'initial');
+    console.log(`[setup-dev-data] initialized git repo`);
+  }
+
+  const gitsheetsDir = join(targetPath, '.gitsheets');
+  await mkdir(gitsheetsDir, { recursive: true });
+
+  let wroteAny = false;
+  for (const { name, root, path } of SHEET_CONFIGS) {
+    const configPath = join(gitsheetsDir, `${name}.toml`);
+    if (existsSync(configPath)) {
+      console.log(`[setup-dev-data] skip ${name}.toml (already exists)`);
+      continue;
+    }
+    await writeFile(configPath, configToml(root, path), 'utf8');
+    wroteAny = true;
+    console.log(`[setup-dev-data] wrote ${name}.toml`);
+  }
+
+  if (!wroteAny) {
+    console.log(`[setup-dev-data] all sheet configs already present — nothing to commit`);
+    return;
+  }
+
+  await git('add', '.gitsheets');
+  const { stdout: porcelain } = await exec('git', ['status', '--porcelain'], { cwd: targetPath });
+  if (porcelain.trim() === '') {
+    console.log(`[setup-dev-data] nothing to commit (configs were unchanged)`);
+    return;
+  }
+  await git('commit', '-m', 'initial: dev data repo configs');
+  console.log(`[setup-dev-data] committed sheet configs`);
+}
+
+main().catch((err: unknown) => {
+  console.error(`[setup-dev-data] failed:`, err);
+  process.exit(1);
+});