Comparison

How asobi compares to other game backend platforms.

asobi is one Erlang/OTP node containing the game backend, the Lua runtime and the operator console. There are two front doors into it: run the image (ghcr.io/widgrensit/asobi) and write Lua, or depend on the Hex package and write Erlang. Same node, same features, different surface.

The asobi column is checked against this repository. The other columns are summarised from each vendor's own public documentation (Nakama, Colyseus, PlayFab) and were last read on 2026-08-06. Check them against the vendor before you make a decision on one.

Feature matrix

Feature	asobi	Nakama	Colyseus	PlayFab
Runtime	BEAM (Erlang/OTP)	Go	Node.js	Cloud
Authentication	Built-in	Built-in	Plugin	Built-in
Anonymous / guest auth	Built-in, upgradeable, opt-in	Built-in	Manual	Built-in
Player management	Built-in	Built-in	Manual	Built-in
Real-time multiplayer	WebSocket	WebSocket	WebSocket	WebSocket
Server-authoritative game loop	Built-in, tick-based	Lua / Go / TS runtime	Room-based	CloudScript
Matchmaking	Modes plus pluggable strategies	Query-based	Manual	Built-in
Leaderboards	ETS reads, PostgreSQL persistence	Built-in	Manual	Built-in
Virtual economy	Wallets, store, inventory	IAP validation	Manual	Built-in
Friends / groups	Built-in	Built-in	Manual	Built-in
Chat	Built-in, channels plus DMs	Built-in	Manual	Manual
Tournaments	Built-in	Built-in	Manual	Manual
Cloud saves	Built-in	Storage API	Manual	Built-in
Notifications	Built-in	Built-in	Manual	Built-in
Background jobs	Shigoto, built-in	Manual	Manual	Scheduled tasks
Custom server-side logic	Lua callbacks plus extension RPC	Runtime modules and RPCs	Room handlers	CloudScript
Operator console	Built-in, read-only	Nakama Console, mutating	Monitor	Game Manager
Database	PostgreSQL, Kura ORM	PostgreSQL or CockroachDB	MongoDB / custom	Managed
Self-hosted	Yes	Yes	Yes	No

Two rows are worth reading twice.

The console is a React SPA served from priv/console by the same node that serves the game. Core's ops routes are reads apart from erasing and exporting one player; the third mutating route is /api/v1/ops/ext/:extension/:action, whose behaviour comes from an installed extension. So there is no ban, kick, grant, refund or match-end button. Nakama Console and PlayFab Game Manager both mutate; if you are moving from one of those, that is a real gap. See Operator console.

Custom server-side logic that is not per-match goes over the WebSocket as rpc.call with {protocol: 1, method, params}, answered by rpc.ok or rpc.error and correlated by cid. All seven client SDKs speak it. That is the replacement for a Nakama RPC, a PlayFab CloudScript function and a Hathora custom message. See Extensions.

Runtime characteristics

Concern	asobi (BEAM)	Nakama (Go)	Colyseus (Node.js)
Garbage collection	Per-process, isolated per match	Stop-the-world	Stop-the-world
Fault tolerance	OTP supervision, crashed matches restart	Panic recovery, manual	Process crash, manual
Live game-logic reload	Lua re-evaluated in place on the next tick	Restart required	Restart required
Pub/sub	`pg`, cluster-native	Built-in plus optional Redis	Built-in, single node
In-memory state	ETS and process heaps	In-process maps	In-process objects
Clustering	Distributed Erlang, built in	etcd / Consul	Redis, presence only
Scheduling	Pre-emptive, fair across all processes	Cooperative goroutines	Single-threaded event loop

Live reload is a Lua mechanism, not an OTP release upgrade: the runtime stats the script file each tick, and a changed mtime re-executes the script body against the running Luerl state, re-declaring globals and functions while in-flight game state survives. It needs the game directory to be a live mount. asobi ships no appup or relup, so upgrading the node itself is a restart.

Connection density on a single node is 3,000-7,000 concurrent WebSocket connections measured on 8 cores, at 4.4ms p50 round-trip with 3,500 connections. Each connection costs ~13-20KB, so at that concurrency the ceiling is CPU spent on message processing, not memory. Figures and method are in Benchmarks.

When to choose asobi

You want a single deployable with auth, matchmaking, economy, social and real-time multiplayer.
You need fault-tolerant game sessions that survive crashes without losing state.
You want hot-reloadable Lua so bug fixes ship without kicking players.
You are building for many simultaneous matches or worlds.
You prefer self-hosted Apache-2.0 over a closed managed cloud, with a real exit runbook (see Exit guarantee).
You want a PostgreSQL-backed system with a proper ORM.

When to choose something else

You are building a twitch FPS, fighting game or racer, where what kills you is the retransmission tail on a lossy path rather than the median RTT. Run the simulation over your own UDP netcode and use asobi for everything around it, or take a physics-first product for the simulation layer. Worth checking the alternatives on this point specifically rather than assuming: a production UDP game-state transport is rarer in this category than the marketing suggests, and several of the obvious comparisons are WebSocket-over-TCP underneath.
You need deep LiveOps tooling (A/B testing, segmentation, push campaigns) today.
You need a fully managed cloud at hyperscaler breadth. asobi's managed version is asobi.dev/cloud, which is the same open-source core rather than a different product - invite-only today, and narrower than self-hosting in ways Cloud lists.
You are building a single-player game that only needs analytics and IAP. Analytics plus a store validator is cheaper than any backend here.

Clustering

Multiple nodes share Postgres and pg-scoped presence, chat and process lookups. Four things stay node-local and change how you deploy: the matchmaker queue, the rate-limit buckets, the console session store and the player-to-world table - so the console needs a sticky route, players queuing against different nodes never match each other, and a player who reconnects to a different node loses their world with no error. That last one is the only item here a player notices and an operator does not, which is why it belongs in the summary rather than only in the full list. Clustering has the rest.

Client SDKs

Seven first-class SDKs: Godot, Defold, LÖVE, Unity, Unreal, JavaScript/TypeScript and Dart/Flutter. flame_asobi is a Flame bridge on top of the Dart SDK rather than an eighth protocol implementation. The table with guides and demos is in the README.