diff --git a/src/controllers/groups.js b/src/controllers/groups.js
index 041ba878df..7b5f9a6839 100644
--- a/src/controllers/groups.js
+++ b/src/controllers/groups.js
@@ -189,3 +189,5 @@ groupsController.uploadCover = function (req, res, next) {
 		res.json([{ url: image.url }]);
 	});
 };
+
+require('../promisify')(groupsController);
diff --git a/src/socket.io/groups.js b/src/socket.io/groups.js
index 505c79b04f..d90b536bd5 100644
--- a/src/socket.io/groups.js
+++ b/src/socket.io/groups.js
@@ -1,7 +1,5 @@
 'use strict';
 
-var async = require('async');
-
 var groups = require('../groups');
 var meta = require('../meta');
 var user = require('../user');
@@ -12,356 +10,293 @@ var privileges = require('../privileges');
 
 var SocketGroups = module.exports;
 
-SocketGroups.before = function (socket, method, data, next) {
+SocketGroups.before = async (socket, method, data) => {
 	if (!data) {
-		return next(new Error('[[error:invalid-data]]'));
+		throw new Error('[[error:invalid-data]]');
 	}
-	next();
 };
 
-SocketGroups.join = function (socket, data, callback) {
+SocketGroups.join = async (socket, data) => {
 	if (socket.uid <= 0) {
-		return callback(new Error('[[error:invalid-uid]]'));
+		throw new Error('[[error:invalid-uid]]');
 	}
 
 	if (data.groupName === 'administrators' || groups.isPrivilegeGroup(data.groupName)) {
-		return callback(new Error('[[error:not-allowed]]'));
+		throw new Error('[[error:not-allowed]]');
+	}
+
+	const exists = await groups.exists(data.groupName);
+	if (!exists) {
+		throw new Error('[[error:no-group]]');
 	}
 
-	async.waterfall([
-		function (next) {
-			groups.exists(data.groupName, next);
-		},
-		function (exists, next) {
-			if (!exists) {
-				return next(new Error('[[error:no-group]]'));
-			}
-
-			if (!meta.config.allowPrivateGroups) {
-				groups.join(data.groupName, socket.uid, callback);
-				return;
-			}
-
-			async.parallel({
-				isAdmin: async.apply(user.isAdministrator, socket.uid),
-				groupData: async.apply(groups.getGroupData, data.groupName),
-			}, next);
-		},
-		function (results, next) {
-			if (results.groupData.private && results.groupData.disableJoinRequests) {
-				return next(new Error('[[error:join-requests-disabled]]'));
-			}
-
-			if (!results.groupData.private || results.isAdmin) {
-				groups.join(data.groupName, socket.uid, next);
-			} else {
-				groups.requestMembership(data.groupName, socket.uid, next);
-			}
-		},
-	], callback);
+	if (!meta.config.allowPrivateGroups) {
+		await groups.join(data.groupName, socket.uid);
+		return;
+	}
+
+	const results = await utils.promiseParallel({
+		isAdmin: await user.isAdministrator(socket.uid),
+		groupData: await groups.getGroupData(data.groupName),
+	});
+
+	if (results.groupData.private && results.groupData.disableJoinRequests) {
+		throw new Error('[[error:join-requests-disabled]]');
+	}
+
+	if (!results.groupData.private || results.isAdmin) {
+		await groups.join(data.groupName, socket.uid);
+	} else {
+		await groups.requestMembership(data.groupName, socket.uid);
+	}
 };
 
-SocketGroups.leave = function (socket, data, callback) {
+SocketGroups.leave = async (socket, data) => {
 	if (socket.uid <= 0) {
-		return callback(new Error('[[error:invalid-uid]]'));
+		throw new Error('[[error:invalid-uid]]');
 	}
 
 	if (data.groupName === 'administrators') {
-		return callback(new Error('[[error:cant-remove-self-as-admin]]'));
+		throw new Error('[[error:cant-remove-self-as-admin]]');
 	}
 
-	groups.leave(data.groupName, socket.uid, callback);
+	await groups.leave(data.groupName, socket.uid);
 };
 
-SocketGroups.addMember = isOwner(function (socket, data, callback) {
+SocketGroups.addMember = async (socket, data) => {
+	await isOwner(socket, data);
 	if (data.groupName === 'administrators' || groups.isPrivilegeGroup(data.groupName)) {
-		return callback(new Error('[[error:not-allowed]]'));
+		throw new Error('[[error:not-allowed]]');
+	}
+	await groups.join(data.groupName, data.uid);
+};
+
+async function isOwner(socket, data) {
+	const results = await utils.promiseParallel({
+		isAdmin: await user.isAdministrator(socket.uid),
+		isGlobalModerator: await user.isGlobalModerator(socket.uid),
+		isOwner: await groups.ownership.isOwner(socket.uid, data.groupName),
+		group: await groups.getGroupData(data.groupName),
+	});
+
+	var isOwner = results.isOwner || results.isAdmin || (results.isGlobalModerator && !results.group.system);
+	if (!isOwner) {
+		throw new Error('[[error:no-privileges]]');
 	}
-	groups.join(data.groupName, data.uid, callback);
-});
-
-function isOwner(next) {
-	return function (socket, data, callback) {
-		async.parallel({
-			isAdmin: async.apply(user.isAdministrator, socket.uid),
-			isGlobalModerator: async.apply(user.isGlobalModerator, socket.uid),
-			isOwner: async.apply(groups.ownership.isOwner, socket.uid, data.groupName),
-			group: async.apply(groups.getGroupData, data.groupName),
-		}, function (err, results) {
-			if (err) {
-				return callback(err);
-			}
-			var isOwner = results.isOwner || results.isAdmin || (results.isGlobalModerator && !results.group.system);
-			if (!isOwner) {
-				return callback(new Error('[[error:no-privileges]]'));
-			}
-			next(socket, data, callback);
-		});
-	};
 }
 
-function isInvited(next) {
-	return function (socket, data, callback) {
-		groups.isInvited(socket.uid, data.groupName, function (err, invited) {
-			if (err || !invited) {
-				return callback(err || new Error('[[error:not-invited]]'));
-			}
-			next(socket, data, callback);
-		});
-	};
+async function isInvited(socket, data) {
+	const invited = await groups.isInvited(socket.uid, data.groupName);
+	if (!invited) {
+		throw new Error('[[error:not-invited]]');
+	}
 }
 
-SocketGroups.grant = isOwner(function (socket, data, callback) {
-	groups.ownership.grant(data.toUid, data.groupName, callback);
-});
-
-SocketGroups.rescind = isOwner(function (socket, data, callback) {
-	groups.ownership.rescind(data.toUid, data.groupName, callback);
-});
-
-SocketGroups.accept = isOwner(function (socket, data, callback) {
-	async.waterfall([
-		function (next) {
-			groups.acceptMembership(data.groupName, data.toUid, next);
-		},
-		function (next) {
-			events.log({
-				type: 'accept-membership',
-				uid: socket.uid,
-				ip: socket.ip,
-				groupName: data.groupName,
-				targetUid: data.toUid,
-			});
-			setImmediate(next);
-		},
-	], callback);
-});
-
-SocketGroups.reject = isOwner(function (socket, data, callback) {
-	async.waterfall([
-		function (next) {
-			groups.rejectMembership(data.groupName, data.toUid, next);
-		},
-		function (next) {
-			events.log({
-				type: 'reject-membership',
-				uid: socket.uid,
-				ip: socket.ip,
-				groupName: data.groupName,
-				targetUid: data.toUid,
-			});
-			setImmediate(next);
-		},
-	], callback);
-});
-
-SocketGroups.acceptAll = isOwner(function (socket, data, callback) {
-	acceptRejectAll(SocketGroups.accept, socket, data, callback);
-});
-
-SocketGroups.rejectAll = isOwner(function (socket, data, callback) {
-	acceptRejectAll(SocketGroups.reject, socket, data, callback);
-});
-
-function acceptRejectAll(method, socket, data, callback) {
-	async.waterfall([
-		function (next) {
-			groups.getPending(data.groupName, next);
-		},
-		function (uids, next) {
-			async.each(uids, function (uid, next) {
-				method(socket, { groupName: data.groupName, toUid: uid }, next);
-			}, next);
-		},
-	], callback);
+SocketGroups.grant = async (socket, data) => {
+	await isOwner(socket, data);
+	await groups.ownership.grant(data.toUid, data.groupName);
+};
+
+SocketGroups.rescind = async (socket, data) => {
+	await isOwner(socket, data);
+	await groups.ownership.rescind(data.toUid, data.groupName);
+};
+
+SocketGroups.accept = async (socket, data) => {
+	await isOwner(socket, data);
+	await groups.acceptMembership(data.groupName, data.toUid);
+	events.log({
+		type: 'accept-membership',
+		uid: socket.uid,
+		ip: socket.ip,
+		groupName: data.groupName,
+		targetUid: data.toUid,
+	});
+};
+
+SocketGroups.reject = async (socket, data) => {
+	await isOwner(socket, data);
+	await groups.rejectMembership(data.groupName, data.toUid);
+	events.log({
+		type: 'reject-membership',
+		uid: socket.uid,
+		ip: socket.ip,
+		groupName: data.groupName,
+		targetUid: data.toUid,
+	});
+};
+
+SocketGroups.acceptAll = async (socket, data) => {
+	await isOwner(socket, data);
+	await acceptRejectAll(SocketGroups.accept, socket, data);
+};
+
+SocketGroups.rejectAll = async (socket, data) => {
+	await isOwner(socket, data);
+	await acceptRejectAll(SocketGroups.reject, socket, data);
+};
+
+async function acceptRejectAll(method, socket, data) {
+	const uids = groups.getPending(data.groupName);
+	await new Promise(uids.forEach(async (uid) => {
+		await method(socket, { groupName: data.groupName, toUid: uid });
+	}));
 }
 
-SocketGroups.issueInvite = isOwner(function (socket, data, callback) {
-	groups.invite(data.groupName, data.toUid, callback);
-});
+SocketGroups.issueInvite = async (socket, data) => {
+	await isOwner(socket, data);
+	await groups.invite(data.groupName, data.toUid);
+};
 
-SocketGroups.issueMassInvite = isOwner(function (socket, data, callback) {
+SocketGroups.issueMassInvite = async (socket, data) => {
+	await isOwner(socket, data);
 	if (!data || !data.usernames || !data.groupName) {
-		return callback(new Error('[[error:invalid-data]]'));
+		throw new Error('[[error:invalid-data]]');
 	}
 	var usernames = String(data.usernames).split(',');
 	usernames = usernames.map(function (username) {
 		return username && username.trim();
 	});
 
-	async.waterfall([
-		function (next) {
-			user.getUidsByUsernames(usernames, next);
-		},
-		function (uids, next) {
-			uids = uids.filter(function (uid) {
-				return !!uid && parseInt(uid, 10);
-			});
+	let uids = await user.getUidsByUsernames(usernames);
+	uids = uids.filter(function (uid) {
+		return !!uid && parseInt(uid, 10);
+	});
 
-			async.eachSeries(uids, function (uid, next) {
-				groups.invite(data.groupName, uid, next);
-			}, next);
-		},
-	], callback);
-});
+	// eslint-disable-next-line guard-for-in
+	for (const i in uids) {
+		// eslint-disable-next-line no-await-in-loop
+		await groups.invite(data.groupName, uids[i]);
+	}
+};
 
-SocketGroups.rescindInvite = isOwner(function (socket, data, callback) {
-	groups.rejectMembership(data.groupName, data.toUid, callback);
-});
+SocketGroups.rescindInvite = async (socket, data) => {
+	await isOwner(socket, data);
+	await groups.rejectMembership(data.groupName, data.toUid);
+};
 
-SocketGroups.acceptInvite = isInvited(function (socket, data, callback) {
-	groups.acceptMembership(data.groupName, socket.uid, callback);
-});
+SocketGroups.acceptInvite = async (socket, data) => {
+	await isInvited(socket, data);
+	await groups.acceptMembership(data.groupName, socket.uid);
+};
 
-SocketGroups.rejectInvite = isInvited(function (socket, data, callback) {
-	groups.rejectMembership(data.groupName, socket.uid, callback);
-});
+SocketGroups.rejectInvite = async (socket, data) => {
+	await isInvited(socket, data);
+	await groups.rejectMembership(data.groupName, socket.uid);
+};
 
-SocketGroups.update = isOwner(function (socket, data, callback) {
-	groups.update(data.groupName, data.values, callback);
-});
+SocketGroups.update = async (socket, data) => {
+	await isOwner(socket, data);
+	await groups.update(data.groupName, data.values);
+};
 
 
-SocketGroups.kick = isOwner(function (socket, data, callback) {
+SocketGroups.kick = async (socket, data) => {
+	await isOwner(socket, data);
 	if (socket.uid === parseInt(data.uid, 10)) {
-		return callback(new Error('[[error:cant-kick-self]]'));
+		throw new Error('[[error:cant-kick-self]]');
 	}
 
-	async.waterfall([
-		function (next) {
-			groups.ownership.isOwner(data.uid, data.groupName, next);
-		},
-		function (isOwner, next) {
-			groups.kick(data.uid, data.groupName, isOwner, next);
-		},
-	], callback);
-});
-
-SocketGroups.create = function (socket, data, callback) {
+	const isOwnerBit = await groups.ownership.isOwner(data.uid, data.groupName);
+	await groups.kick(data.uid, data.groupName, isOwnerBit);
+};
+
+SocketGroups.create = async (socket, data) => {
 	if (!socket.uid) {
-		return callback(new Error('[[error:no-privileges]]'));
+		throw new Error('[[error:no-privileges]]');
 	} else if (groups.isPrivilegeGroup(data.name)) {
-		return callback(new Error('[[error:invalid-group-name]]'));
+		throw new Error('[[error:invalid-group-name]]');
 	}
 
-	async.waterfall([
-		function (next) {
-			privileges.global.can('group:create', socket.uid, next);
-		},
-		function (canCreate, next) {
-			if (!canCreate) {
-				return next(new Error('[[error:no-privileges]]'));
-			}
-			data.ownerUid = socket.uid;
-			groups.create(data, next);
-		},
-	], callback);
+	const canCreate = await privileges.global.can('group:create', socket.uid);
+	if (!canCreate) {
+		throw new Error('[[error:no-privileges]]');
+	}
+	data.ownerUid = socket.uid;
+	await groups.create(data);
 };
 
-SocketGroups.delete = isOwner(function (socket, data, callback) {
-	if (data.groupName === 'administrators' ||
-		data.groupName === 'registered-users' ||
-		data.groupName === 'guests' ||
-		data.groupName === 'Global Moderators') {
-		return callback(new Error('[[error:not-allowed]]'));
+SocketGroups.delete = async (socket, data) => {
+	await isOwner(socket, data);
+	if (
+		data.groupName === 'administrators' || data.groupName === 'registered-users' ||
+		data.groupName === 'guests' || data.groupName === 'Global Moderators'
+	) {
+		throw new Error('[[error:not-allowed]]');
 	}
 
-	groups.destroy(data.groupName, callback);
-});
+	await groups.destroy(data.groupName);
+};
 
-SocketGroups.search = function (socket, data, callback) {
+SocketGroups.search = async (socket, data) => {
 	data.options = data.options || {};
 
 	if (!data.query) {
 		var groupsPerPage = 15;
-		groupsController.getGroupsFromSet(socket.uid, data.options.sort, 0, groupsPerPage - 1, function (err, data) {
-			callback(err, !err ? data.groups : null);
-		});
-		return;
+		const groups = await groupsController.getGroupsFromSet(socket.uid, data.options.sort, 0, groupsPerPage - 1);
+		return groups.groups;
 	}
 
-	groups.search(data.query, data.options, callback);
+	await groups.search(data.query, data.options);
 };
 
-SocketGroups.loadMore = function (socket, data, callback) {
+SocketGroups.loadMore = async (socket, data) => {
 	if (!data.sort || !utils.isNumber(data.after) || parseInt(data.after, 10) < 0) {
-		return callback(new Error('[[error:invalid-data]]'));
+		throw new Error('[[error:invalid-data]]');
 	}
 
 	var groupsPerPage = 9;
 	var start = parseInt(data.after, 10);
 	var stop = start + groupsPerPage - 1;
-	groupsController.getGroupsFromSet(socket.uid, data.sort, start, stop, callback);
+	await groupsController.getGroupsFromSet(socket.uid, data.sort, start, stop);
 };
 
-SocketGroups.searchMembers = function (socket, data, callback) {
+SocketGroups.searchMembers = async (socket, data) => {
 	data.uid = socket.uid;
-	groups.searchMembers(data, callback);
+	await groups.searchMembers(data);
 };
 
-SocketGroups.loadMoreMembers = function (socket, data, callback) {
+SocketGroups.loadMoreMembers = async (socket, data) => {
 	if (!data.groupName || !utils.isNumber(data.after) || parseInt(data.after, 10) < 0) {
-		return callback(new Error('[[error:invalid-data]]'));
+		throw new Error('[[error:invalid-data]]');
 	}
 	data.after = parseInt(data.after, 10);
-	async.waterfall([
-		function (next) {
-			user.getUsersFromSet('group:' + data.groupName + ':members', socket.uid, data.after, data.after + 9, next);
-		},
-		function (users, next) {
-			next(null, {
-				users: users,
-				nextStart: data.after + 10,
-			});
-		},
-	], callback);
+	const users = user.getUsersFromSet('group:' + data.groupName + ':members', socket.uid, data.after, data.after + 9);
+	return {
+		users: users,
+		nextStart: data.after + 10,
+	};
 };
 
 SocketGroups.cover = {};
 
-SocketGroups.cover.update = function (socket, data, callback) {
+SocketGroups.cover.update = async (socket, data) => {
 	if (!socket.uid) {
-		return callback(new Error('[[error:no-privileges]]'));
+		throw new Error('[[error:no-privileges]]');
 	}
 
-	async.waterfall([
-		function (next) {
-			canModifyGroup(socket.uid, data.groupName, next);
-		},
-		function (next) {
-			groups.updateCover(socket.uid, data, next);
-		},
-	], callback);
+	await canModifyGroup(socket.uid, data.groupName);
+	await groups.updateCover(socket.uid, data);
 };
 
-SocketGroups.cover.remove = function (socket, data, callback) {
+SocketGroups.cover.remove = async (socket, data) => {
 	if (!socket.uid) {
-		return callback(new Error('[[error:no-privileges]]'));
+		throw new Error('[[error:no-privileges]]');
 	}
 
-	async.waterfall([
-		function (next) {
-			canModifyGroup(socket.uid, data.groupName, next);
-		},
-		function (next) {
-			groups.removeCover(data, next);
-		},
-	], callback);
+	await canModifyGroup(socket.uid, data.groupName);
+	await groups.removeCover(socket.uid, data);
 };
 
-function canModifyGroup(uid, groupName, callback) {
-	async.waterfall([
-		function (next) {
-			async.parallel({
-				isOwner: async.apply(groups.ownership.isOwner, uid, groupName),
-				isAdminOrGlobalMod: async.apply(user.isAdminOrGlobalMod, uid),
-			}, next);
-		},
-		function (results, next) {
-			if (!results.isOwner && !results.isAdminOrGlobalMod) {
-				return next(new Error('[[error:no-privileges]]'));
-			}
-			next();
-		},
-	], callback);
+async function canModifyGroup(uid, groupName) {
+	const results = await utils.promiseParallel({
+		isOwner: groups.ownership.isOwner(uid, groupName),
+		isAdminOrGlobalMod: user.isAdminOrGlobalMod(uid),
+	});
+
+	if (!results.isOwner && !results.isAdminOrGlobalMod) {
+		throw new Error('[[error:no-privileges]]');
+	}
 }
+
+require('../promisify')(SocketGroups);