diff --git a/server/src/app.ts b/server/src/app.ts
index 5cef627..dd68076 100644
--- a/server/src/app.ts
+++ b/server/src/app.ts
@@ -10,6 +10,7 @@ import { authRouter } from './routes/auth.js'
 import { docsRouter } from './routes/docs.js'
 import { betsRouter } from './routes/bets.js'
 import { paymentsRouter } from './routes/payments.js'
+import { tournamentsRouter } from './routes/tournaments.js'
 import { rateLimit } from './middleware/rate-limit.js'
 
 import { existsSync, readFileSync } from 'fs'
@@ -58,6 +59,7 @@ app.route('/api/queue', queueRouter)
 app.route('/api/docs', docsRouter)
 app.route('/api/bets', betsRouter)
 app.route('/api/payments', paymentsRouter)
+app.route('/api/tournaments', tournamentsRouter)
 
 // In production, serve the frontend SPA
 const __dirname = dirname(fileURLToPath(import.meta.url))
diff --git a/server/src/routes/tournaments.ts b/server/src/routes/tournaments.ts
new file mode 100644
index 0000000..f3baf04
--- /dev/null
+++ b/server/src/routes/tournaments.ts
@@ -0,0 +1,98 @@
+import { Hono } from 'hono'
+import { db, schema } from '../db/index.js'
+import { eq } from 'drizzle-orm'
+import {
+  createTournament,
+  joinTournament,
+  startTournament,
+  getTournamentBracket,
+  listTournaments,
+} from '../engine/tournaments.js'
+
+const CREATOR_PUBKEY = 'da5e0c1b646bdb13c2300f805b0ca3e5afe5b052c594ce78bac8978d21c3fa39'
+
+export const tournamentsRouter = new Hono()
+
+// List tournaments (optionally filter by status)
+tournamentsRouter.get('/', async (c) => {
+  const status = c.req.query('status') as 'open' | 'active' | 'finished' | undefined
+  const tournaments = listTournaments(status)
+  return c.json({ tournaments })
+})
+
+// Get tournament bracket
+tournamentsRouter.get('/:id', async (c) => {
+  const id = c.req.param('id')
+  const bracket = getTournamentBracket(id)
+  if (!bracket) return c.json({ error: 'Tournament not found' }, 404)
+  return c.json(bracket)
+})
+
+// Create a tournament (admin only — creator pubkey required)
+tournamentsRouter.post('/', async (c) => {
+  const body = await c.req.json<{
+    pubkey: string
+    name: string
+    format?: 'single_elim' | 'round_robin'
+    size?: 8 | 16 | 32
+    entrySats?: number
+  }>()
+
+  if (body.pubkey !== CREATOR_PUBKEY) {
+    return c.json({ error: 'Only the creator can create tournaments' }, 403)
+  }
+
+  if (!body.name || body.name.length < 1 || body.name.length > 100) {
+    return c.json({ error: 'Tournament name required (1-100 chars)' }, 400)
+  }
+
+  const format = body.format ?? 'single_elim'
+  const size = body.size ?? 8
+  if (![8, 16, 32].includes(size)) {
+    return c.json({ error: 'Size must be 8, 16, or 32' }, 400)
+  }
+
+  const id = createTournament(body.name, format, size, body.entrySats ?? 0)
+  return c.json({ id, name: body.name, format, size }, 201)
+})
+
+// Join a tournament
+tournamentsRouter.post('/:id/join', async (c) => {
+  const tournamentId = c.req.param('id')
+  const body = await c.req.json<{ pubkey: string; paymentId?: string }>()
+
+  if (!body.pubkey) return c.json({ error: 'pubkey required' }, 400)
+
+  // Look up bot by pubkey
+  const bot = db.select().from(schema.bots)
+    .where(eq(schema.bots.publicKey, body.pubkey))
+    .get()
+  if (!bot) return c.json({ error: 'Bot not found for this pubkey' }, 404)
+
+  try {
+    const entryId = joinTournament(tournamentId, bot.id, body.paymentId)
+    return c.json({ entryId, botId: bot.id })
+  } catch (err) {
+    const message = err instanceof Error ? err.message : String(err)
+    return c.json({ error: message }, 400)
+  }
+})
+
+// Start a tournament (admin only)
+tournamentsRouter.post('/:id/start', async (c) => {
+  const tournamentId = c.req.param('id')
+  const body = await c.req.json<{ pubkey: string }>()
+
+  if (body.pubkey !== CREATOR_PUBKEY) {
+    return c.json({ error: 'Only the creator can start tournaments' }, 403)
+  }
+
+  try {
+    startTournament(tournamentId)
+    const bracket = getTournamentBracket(tournamentId)
+    return c.json({ status: 'active', bracket })
+  } catch (err) {
+    const message = err instanceof Error ? err.message : String(err)
+    return c.json({ error: message }, 400)
+  }
+})