diff --git a/src/api/group.ts b/src/api/group.ts
new file mode 100644
index 0000000..7f9d442
--- /dev/null
+++ b/src/api/group.ts
@@ -0,0 +1,41 @@
+import { Router } from 'express';
+import { getGroupByID } from '../data';
+import { GroupModel, PoolModel } from '../models';
+
+export const router = Router();
+
+router.get('/:groupID/pools', async (req, res) => {
+	let groupID = req.params.groupID;
+	let pools = await PoolModel.find({ group_id: groupID }).exec();
+
+	res.json({ status: 'success', data: pools });
+});
+
+router.get('/:groupID', async (req, res) => {
+	let groupID = req.params.groupID;
+	let group = await getGroupByID(groupID);
+
+	if (group) {
+		res.json({ status: 'success', data: group });
+	} else {
+		res.json({ status: 'error', error: 'not_found' });
+	}
+});
+
+router.post('/', async (req, res) => {
+	const userID = req.session.accountID;
+	const name = req.body.name;
+
+	const group = new GroupModel();
+	group.set('name', name);
+	group.set('creator_id', userID);
+	group
+		.save()
+		.then((group) => {
+			res.json({ status: 'success', id: group._id });
+		})
+		.catch((err) => {
+			console.error('Error when creating a group:', err);
+			res.json({ status: 'error' });
+		});
+});
diff --git a/src/api/index.ts b/src/api/index.ts
index 0172191..8ad7c16 100644
--- a/src/api/index.ts
+++ b/src/api/index.ts
@@ -1,93 +1,15 @@
 import { Router } from 'express';
 import { createSessionFromCodeAndProvider } from '../auth';
-import { getGroupByID, getPoolByID, getPoolsWithUser } from '../data';
-import { GroupModel, PoolModel } from '../models';
 
 import * as user from './user';
 import * as pool from './pool';
+import * as group from './group';
 
 export const router = Router();
 
 router.use('/user', user.router);
 router.use('/pool', pool.router);
-
-router.get('/group', async (req, res) => {
-	if (typeof req.query.groupID != 'string') {
-		return res.json({ status: 'error' });
-	}
-
-	let groupID = req.query.groupID;
-	let group = await getGroupByID(groupID);
-
-	if (group) {
-		res.json({ status: 'success', data: group });
-	} else {
-		res.json({ status: 'error', error: 'not_found' });
-	}
-});
-
-router.get('/group_pools', async (req, res) => {
-	if (typeof req.query.groupID != 'string') {
-		res.json({ status: 'error', error: 'need_group_id' });
-		return;
-	}
-
-	let groupID = req.query.groupID;
-	let pools = await PoolModel.find({ group_id: groupID }).exec();
-
-	res.json({ status: 'success', data: pools });
-});
-
-router.post('/join_pool', async (req, res) => {
-	if (!req.session.accountID) {
-		return res.json({ status: 'error', error: 'need_login' });
-	} else {
-		let poolID = req.body.id;
-		let userID = req.session.accountID;
-
-		await PoolModel.findByIdAndUpdate(poolID, {
-			$addToSet: { participant_ids: userID },
-		}).exec();
-
-		res.json({ status: 'success' });
-	}
-});
-
-router.post('/group', (req, res) => {
-	if (req.session.accountID == null) {
-		res.status(401);
-		return res.json({ status: 'error', error: 'need_login' });
-	}
-
-	const userID = req.session.accountID;
-	const name = req.body.name;
-
-	const group = new GroupModel();
-	group.set('name', name);
-	group.set('creator_id', userID);
-	group
-		.save()
-		.then((group) => {
-			res.json({ status: 'success', id: group._id });
-		})
-		.catch((err) => {
-			console.error('Error when creating a group:', err);
-			res.json({ status: 'error' });
-		});
-});
-
-router.get('/my_pools', async (req, res) => {
-	if (req.session.accountID == null) {
-		res.status(401);
-		return res.json({ status: 'error', error: 'need_login' });
-	}
-	let pools = await getPoolsWithUser(req.session.accountID);
-	if (pools) {
-		res.json({ status: 'success', data: pools });
-	} else {
-		res.json({ status: 'error', error: 'not_found' });
-	}
-});
+router.use('/group', group.router);
 
 router.post('/create_session', (req, res) => {
 	const { code, provider } = req.body;
diff --git a/src/api/pool.ts b/src/api/pool.ts
index 893bb4f..6614a3f 100644
--- a/src/api/pool.ts
+++ b/src/api/pool.ts
@@ -5,11 +5,22 @@ import requireApiAuth from '../requireApiAuth';
 
 export const router = Router();
 
+router.post('/:poolID/join', async (req, res) => {
+	const userID = req.session.accountID;
+	const poolID = req.params.poolID;
+
+	await PoolModel.findByIdAndUpdate(poolID, {
+		$addToSet: { participant_ids: userID },
+	}).exec();
+
+	res.json({ status: 'success' });
+});
+
 router.get('/:poolID', async (req, res) => {
 	const pool = await PoolModel.findById(new ObjectID(req.params.poolID)).exec();
 
 	if (pool) {
-		res.json({ status: 'success', data: pool });
+		res.json({ status: 'success', data: pool.toJSON() });
 	} else {
 		res.json({ status: 'error', error: 'not_found' });
 	}