diff --git a/src/lib/db.ts b/src/lib/db.ts
new file mode 100644
index 0000000..537d0aa
--- /dev/null
+++ b/src/lib/db.ts
@@ -0,0 +1,47 @@
+import Database from 'better-sqlite3';
+import { mkdirSync } from 'node:fs';
+import { dirname } from 'node:path';
+
+const SCHEMA = `
+CREATE TABLE IF NOT EXISTS posts (
+  id INTEGER PRIMARY KEY AUTOINCREMENT,
+  title TEXT NOT NULL,
+  slug TEXT NOT NULL UNIQUE,
+  category TEXT NOT NULL,
+  excerpt TEXT NOT NULL DEFAULT '',
+  body_html TEXT NOT NULL DEFAULT '',
+  cover TEXT,
+  draft INTEGER NOT NULL DEFAULT 1,
+  published_at TEXT,
+  created_at TEXT NOT NULL DEFAULT (datetime('now')),
+  updated_at TEXT NOT NULL DEFAULT (datetime('now'))
+);
+CREATE TABLE IF NOT EXISTS users (
+  id INTEGER PRIMARY KEY AUTOINCREMENT,
+  username TEXT NOT NULL UNIQUE,
+  password_hash TEXT NOT NULL
+);
+CREATE TABLE IF NOT EXISTS sessions (
+  token TEXT PRIMARY KEY,
+  user_id INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+  expires_at TEXT NOT NULL
+);
+CREATE INDEX IF NOT EXISTS idx_posts_pub ON posts (draft, published_at DESC);
+`;
+
+export function createDb(path?: string): Database.Database {
+  const p = path ?? process.env.DB_PATH ?? 'data/insanitylab.db';
+  if (p !== ':memory:') mkdirSync(dirname(p), { recursive: true });
+  const db = new Database(p);
+  db.pragma('journal_mode = WAL');
+  db.pragma('foreign_keys = ON');
+  db.exec(SCHEMA);
+  return db;
+}
+
+let singleton: Database.Database | null = null;
+
+export function getDb(): Database.Database {
+  if (!singleton) singleton = createDb();
+  return singleton;
+}
diff --git a/src/lib/posts.ts b/src/lib/posts.ts
new file mode 100644
index 0000000..dad9159
--- /dev/null
+++ b/src/lib/posts.ts
@@ -0,0 +1,74 @@
+import type Database from 'better-sqlite3';
+
+export interface Post {
+  id: number; title: string; slug: string; category: string; excerpt: string;
+  body_html: string; cover: string | null; draft: number;
+  published_at: string | null; created_at: string; updated_at: string;
+}
+
+export interface PostInput {
+  title: string; slug: string; category: string; excerpt: string;
+  body_html: string; cover?: string | null; draft: boolean;
+}
+
+export function createPost(db: Database.Database, input: PostInput): number {
+  const res = db.prepare(
+    `INSERT INTO posts (title, slug, category, excerpt, body_html, cover, draft, published_at)
+     VALUES (@title, @slug, @category, @excerpt, @body_html, @cover, @draft,
+             CASE WHEN @draft = 0 THEN datetime('now') ELSE NULL END)`
+  ).run({ ...input, cover: input.cover ?? null, draft: input.draft ? 1 : 0 });
+  return Number(res.lastInsertRowid);
+}
+
+export function updatePost(db: Database.Database, id: number, input: PostInput): void {
+  db.prepare(
+    `UPDATE posts SET title = @title, slug = @slug, category = @category,
+       excerpt = @excerpt, body_html = @body_html, cover = @cover, draft = @draft,
+       published_at = CASE WHEN @draft = 0 AND published_at IS NULL THEN datetime('now') ELSE published_at END,
+       updated_at = datetime('now')
+     WHERE id = @id`
+  ).run({ ...input, id, cover: input.cover ?? null, draft: input.draft ? 1 : 0 });
+}
+
+export function deletePost(db: Database.Database, id: number): void {
+  db.prepare('DELETE FROM posts WHERE id = ?').run(id);
+}
+
+export function getPostById(db: Database.Database, id: number): Post | undefined {
+  return db.prepare('SELECT * FROM posts WHERE id = ?').get(id) as Post | undefined;
+}
+
+export function getPublishedBySlug(db: Database.Database, slug: string): Post | undefined {
+  return db.prepare('SELECT * FROM posts WHERE slug = ? AND draft = 0').get(slug) as Post | undefined;
+}
+
+export function listPublished(
+  db: Database.Database,
+  opts: { category?: string; page?: number; perPage?: number } = {},
+): { items: Post[]; total: number } {
+  const { category, page = 1, perPage = 9 } = opts;
+  const where = category ? 'WHERE draft = 0 AND category = @category' : 'WHERE draft = 0';
+  const total = (db.prepare(`SELECT COUNT(*) AS n FROM posts ${where}`)
+    .get({ category }) as { n: number }).n;
+  const items = db.prepare(
+    `SELECT * FROM posts ${where} ORDER BY published_at DESC LIMIT @limit OFFSET @offset`
+  ).all({ category, limit: perPage, offset: (page - 1) * perPage }) as Post[];
+  return { items, total };
+}
+
+export function listAllPosts(db: Database.Database): Post[] {
+  return db.prepare('SELECT * FROM posts ORDER BY updated_at DESC').all() as Post[];
+}
+
+export function listRecent(db: Database.Database, limit = 4): Post[] {
+  return db.prepare(
+    'SELECT * FROM posts WHERE draft = 0 ORDER BY published_at DESC LIMIT ?'
+  ).all(limit) as Post[];
+}
+
+export function listArchiveMonths(db: Database.Database): { month: string; count: number }[] {
+  return db.prepare(
+    `SELECT strftime('%Y-%m', published_at) AS month, COUNT(*) AS count
+     FROM posts WHERE draft = 0 GROUP BY month ORDER BY month DESC`
+  ).all() as { month: string; count: number }[];
+}
diff --git a/tests/posts.test.ts b/tests/posts.test.ts
new file mode 100644
index 0000000..ad373fa
--- /dev/null
+++ b/tests/posts.test.ts
@@ -0,0 +1,74 @@
+import { describe, it, expect, beforeEach } from 'vitest';
+import type Database from 'better-sqlite3';
+import { createDb } from '../src/lib/db';
+import {
+  createPost, updatePost, deletePost, getPostById, getPublishedBySlug,
+  listPublished, listAllPosts, listRecent, listArchiveMonths, type PostInput,
+} from '../src/lib/posts';
+
+let db: Database.Database;
+beforeEach(() => { db = createDb(':memory:'); });
+
+const base: PostInput = {
+  title: 'Titolo', slug: 'titolo', category: 'Contenuti educativi',
+  excerpt: 'estratto', body_html: '<p>corpo</p>', cover: null, draft: false,
+};
+
+describe('posts repository', () => {
+  it('crea e rilegge un post pubblicato', () => {
+    const id = createPost(db, base);
+    const post = getPostById(db, id)!;
+    expect(post.title).toBe('Titolo');
+    expect(post.draft).toBe(0);
+    expect(post.published_at).not.toBeNull();
+  });
+
+  it('bozza non ha published_at e non appare nelle liste pubbliche', () => {
+    const id = createPost(db, { ...base, slug: 'bozza', draft: true });
+    expect(getPostById(db, id)!.published_at).toBeNull();
+    expect(getPublishedBySlug(db, 'bozza')).toBeUndefined();
+    expect(listPublished(db).total).toBe(0);
+    expect(listAllPosts(db)).toHaveLength(1);
+  });
+
+  it('slug duplicato lancia', () => {
+    createPost(db, base);
+    expect(() => createPost(db, base)).toThrow();
+  });
+
+  it('update imposta published_at alla prima pubblicazione e lo conserva', () => {
+    const id = createPost(db, { ...base, draft: true });
+    updatePost(db, id, { ...base, draft: false });
+    const first = getPostById(db, id)!.published_at;
+    expect(first).not.toBeNull();
+    updatePost(db, id, { ...base, title: 'Nuovo', draft: false });
+    expect(getPostById(db, id)!.published_at).toBe(first);
+    expect(getPostById(db, id)!.title).toBe('Nuovo');
+  });
+
+  it('listPublished filtra per categoria e pagina', () => {
+    for (let i = 0; i < 12; i++) {
+      createPost(db, { ...base, slug: `post-${i}`, category: i % 2 ? 'Contenuti educativi' : 'Eventi & Presidi' });
+    }
+    const all = listPublished(db, { page: 1, perPage: 9 });
+    expect(all.total).toBe(12);
+    expect(all.items).toHaveLength(9);
+    const edu = listPublished(db, { category: 'Contenuti educativi' });
+    expect(edu.total).toBe(6);
+  });
+
+  it('delete rimuove', () => {
+    const id = createPost(db, base);
+    deletePost(db, id);
+    expect(getPostById(db, id)).toBeUndefined();
+  });
+
+  it('listRecent e archivio mesi', () => {
+    createPost(db, base);
+    expect(listRecent(db, 4)).toHaveLength(1);
+    const months = listArchiveMonths(db);
+    expect(months).toHaveLength(1);
+    expect(months[0].count).toBe(1);
+    expect(months[0].month).toMatch(/^\d{4}-\d{2}$/);
+  });
+});