diff --git a/src/lib/routing.ts b/src/lib/routing.ts
new file mode 100644
index 0000000..1437152
--- /dev/null
+++ b/src/lib/routing.ts
@@ -0,0 +1,14 @@
+import type { Role } from './db.js';
+
+/**
+ * The path the `/` route should redirect to for a given role, or `null` to
+ * render the existing editorial home content in place.
+ *
+ *  - pilot → null   (keep existing /index.astro content — right audience for it)
+ *  - cab   → /pulse (the member portal is the council's landing)
+ *  - fenja → /pulse (admins see the member view by default; /admin is one click away)
+ */
+export function homeRouteForRole(role: Role): string | null {
+  if (role === 'pilot') return null;
+  return '/pulse';
+}
diff --git a/tests/home-route.test.ts b/tests/home-route.test.ts
new file mode 100644
index 0000000..f3281cf
--- /dev/null
+++ b/tests/home-route.test.ts
@@ -0,0 +1,16 @@
+import { describe, it, expect } from 'vitest';
+import { homeRouteForRole } from '../src/lib/routing.js';
+
+describe('homeRouteForRole — what / does per user role', () => {
+  it('cab → redirect to /pulse', () => {
+    expect(homeRouteForRole('cab')).toBe('/pulse');
+  });
+
+  it('fenja → redirect to /pulse (admins see the member view by default)', () => {
+    expect(homeRouteForRole('fenja')).toBe('/pulse');
+  });
+
+  it('pilot → null (render existing editorial home in place)', () => {
+    expect(homeRouteForRole('pilot')).toBeNull();
+  });
+});
diff --git a/tests/pulse-status.test.ts b/tests/pulse-status.test.ts
new file mode 100644
index 0000000..8499e0b
--- /dev/null
+++ b/tests/pulse-status.test.ts
@@ -0,0 +1,34 @@
+import { describe, it, expect } from 'vitest';
+import { derivePulseStatus } from '../src/lib/db.js';
+
+const ago = (mins: number) => new Date(Date.now() - mins * 60_000).toISOString();
+const ahead = (mins: number) => new Date(Date.now() + mins * 60_000).toISOString();
+
+describe('derivePulseStatus', () => {
+  it('a draft stays a draft regardless of dates', () => {
+    expect(derivePulseStatus('draft', ago(60))).toBe('draft');
+    expect(derivePulseStatus('draft', ahead(60))).toBe('draft');
+  });
+
+  it('a closed pulse stays closed', () => {
+    expect(derivePulseStatus('closed', ahead(60))).toBe('closed');
+    expect(derivePulseStatus('closed', ago(60))).toBe('closed');
+  });
+
+  it('an open pulse stays open while now < closes_at', () => {
+    expect(derivePulseStatus('open', ahead(1))).toBe('open');
+    expect(derivePulseStatus('open', ahead(60 * 24))).toBe('open');
+  });
+
+  it('an open pulse becomes closed once now ≥ closes_at', () => {
+    expect(derivePulseStatus('open', ago(1))).toBe('closed');
+    expect(derivePulseStatus('open', ago(60 * 24))).toBe('closed');
+  });
+
+  it('respects an injected anchor time (deterministic)', () => {
+    const closes = '2026-05-11T12:00:00Z';
+    expect(derivePulseStatus('open', closes, new Date('2026-05-11T11:59:59Z'))).toBe('open');
+    expect(derivePulseStatus('open', closes, new Date('2026-05-11T12:00:00Z'))).toBe('closed');
+    expect(derivePulseStatus('open', closes, new Date('2026-05-11T12:00:01Z'))).toBe('closed');
+  });
+});
diff --git a/tests/setup.ts b/tests/setup.ts
new file mode 100644
index 0000000..421556d
--- /dev/null
+++ b/tests/setup.ts
@@ -0,0 +1,21 @@
+// Test setup: opens an in-memory SQLite database, applies all migrations.
+// Each vitest worker fork gets its own globalThis, so each test file gets a
+// fresh DB. db.ts reads BIFROST_DB_PATH at import time, so this must run first.
+
+process.env.BIFROST_DB_PATH = ':memory:';
+
+import { readFileSync, readdirSync } from 'fs';
+import { join } from 'path';
+import type Database from 'better-sqlite3';
+
+// Importing db.ts triggers the singleton against ':memory:'.
+await import('../src/lib/db.js');
+
+const db = (globalThis as typeof globalThis & { __bifrost_db?: Database.Database }).__bifrost_db;
+if (!db) throw new Error('db singleton did not initialise against :memory:');
+
+const migrationsDir = join(process.cwd(), 'migrations');
+const files = readdirSync(migrationsDir).filter(f => f.endsWith('.sql')).sort();
+for (const file of files) {
+  db.exec(readFileSync(join(migrationsDir, file), 'utf8'));
+}
diff --git a/tests/votes.test.ts b/tests/votes.test.ts
new file mode 100644
index 0000000..3af0377
--- /dev/null
+++ b/tests/votes.test.ts
@@ -0,0 +1,87 @@
+import { describe, it, expect, beforeEach } from 'vitest';
+import type Database from 'better-sqlite3';
+import { createPulse, castVote, getUserVote, countPulseParticipants } from '../src/lib/db.js';
+
+const db = (globalThis as typeof globalThis & { __bifrost_db?: Database.Database }).__bifrost_db!;
+
+function seedUser(name: string, role: 'pilot' | 'cab' | 'fenja' = 'cab'): number {
+  const r = db.prepare(
+    'INSERT INTO users (email, password_hash, name, organisation, role, slug) VALUES (?,?,?,?,?,?)'
+  ).run(`${name}@example.test`, 'x', name, 'TestOrg', role, name.toLowerCase());
+  return Number(r.lastInsertRowid);
+}
+
+function seedPulse(createdBy: number): number {
+  return createPulse({
+    question: 'Should we ship X?',
+    context: null,
+    options: ['Yes', 'No'],
+    opens_at: new Date(Date.now() - 60_000).toISOString(),
+    closes_at: new Date(Date.now() + 60 * 60_000).toISOString(),
+    status: 'open',
+    created_by: createdBy,
+  });
+}
+
+beforeEach(() => {
+  db.exec(`
+    DELETE FROM votes;
+    DELETE FROM pulses;
+    DELETE FROM activity;
+    DELETE FROM users;
+  `);
+});
+
+describe('vote uniqueness (UNIQUE(pulse_id, user_id))', () => {
+  it('rejects a second vote by the same user on the same pulse (first wins)', () => {
+    const admin = seedUser('admin', 'fenja');
+    const voter = seedUser('voter', 'cab');
+    const pulseId = seedPulse(admin);
+
+    castVote(pulseId, voter, 0);
+    // INSERT OR IGNORE → silent no-op for the duplicate.
+    castVote(pulseId, voter, 1);
+
+    expect(getUserVote(pulseId, voter)).toBe(0);
+    expect(countPulseParticipants(pulseId)).toBe(1);
+  });
+
+  it('raises a SqliteError when bypassing OR IGNORE with a raw INSERT', () => {
+    const admin = seedUser('admin', 'fenja');
+    const voter = seedUser('voter', 'cab');
+    const pulseId = seedPulse(admin);
+    castVote(pulseId, voter, 0);
+
+    expect(() =>
+      db.prepare('INSERT INTO votes (pulse_id, user_id, option_index) VALUES (?,?,?)')
+        .run(pulseId, voter, 1)
+    ).toThrow(/UNIQUE constraint failed/);
+  });
+
+  it('allows two different users to vote on the same pulse', () => {
+    const admin = seedUser('admin', 'fenja');
+    const a = seedUser('alice', 'cab');
+    const b = seedUser('bob',   'cab');
+    const pulseId = seedPulse(admin);
+
+    castVote(pulseId, a, 0);
+    castVote(pulseId, b, 1);
+
+    expect(countPulseParticipants(pulseId)).toBe(2);
+    expect(getUserVote(pulseId, a)).toBe(0);
+    expect(getUserVote(pulseId, b)).toBe(1);
+  });
+
+  it('allows the same user to vote on two different pulses', () => {
+    const admin = seedUser('admin', 'fenja');
+    const voter = seedUser('voter', 'cab');
+    const p1 = seedPulse(admin);
+    const p2 = seedPulse(admin);
+
+    castVote(p1, voter, 0);
+    castVote(p2, voter, 1);
+
+    expect(getUserVote(p1, voter)).toBe(0);
+    expect(getUserVote(p2, voter)).toBe(1);
+  });
+});
diff --git a/vitest.config.ts b/vitest.config.ts
new file mode 100644
index 0000000..fe0120b
--- /dev/null
+++ b/vitest.config.ts
@@ -0,0 +1,11 @@
+import { defineConfig } from 'vitest/config';
+
+export default defineConfig({
+  test: {
+    include: ['tests/**/*.test.ts'],
+    setupFiles: ['./tests/setup.ts'],
+    // Each test file gets its own worker → its own globalThis → its own in-memory DB.
+    pool: 'forks',
+    poolOptions: { forks: { singleFork: false } },
+  },
+});