A deployment owns its route table. A route is one template shape and one method
together with the workers that declared it; registration takes the union of the
table and the arriving worker's manifest, deregistration retracts the worker and
drops the routes nothing is left declaring. Manifest stops being a compiled
router and becomes the ordered list a worker declared, so a fleet holds one
table rather than one per replica, and a request resolves in a single walk.
A mixed fleet is the point. Matching each worker's own table in turn already
served heterogeneous methods, but the route the front reported was the first
candidate's while the worker it dispatched to was any of them, and partial and
denied were accumulated across workers whose manifests disagreed. Both become
properties of one table, so the status a request gets and the template the
worker is told are decided together.
Merge order is the lowest position a route holds in any declaring manifest, tied
by shape then method. A fleet declaring one manifest reproduces that manifest's
order, and the result reads off the current set of manifests, so nodes holding
the same fleet agree. This does not preserve any one worker's internal order: a
worker can be handed a request the merged table resolved to a public route while
its own table routes that path to a private one. Merging the declaration chains
in order would hold the property and is not done here;
TestRouteTableMergeOrderInversion carries the case.
Routes are keyed by shape, so /x/{a} and /x/{b} are one route and a renamed path
param does not halve the fleet serving it. Each worker keeps the spelling it
declared, and the preamble carries that, since it is re-serialized per attempt.
The tree holds routes by pointer and is rebuilt only when the route set or its
order moves, so a worker joining or leaving an existing route swaps nothing. A
supersede runs the removal and the addition as one transaction: an unchanged
manifest would otherwise empty every route, drop it, and build a new one under
the same key, leaving the published tree naming routes nothing can reach and no
change to the key set to show for it. A reconnect can also land on a different
agent name or deployment, so the retiring epoch is retracted from its own table.
Ambiguity is now a property of the merged tree, and one worker's template shape
can carry the whole deployment's matcher over its step budget, which leaves no
route decided and so no public flag to clear an ungranted request.
Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
LiveKit: Realtime infrastructure for voice, video, and AI agents
LiveKit is an open source platform for building voice, video, and physical AI agents. This repository is the LiveKit server: a scalable, distributed WebRTC SFU that moves realtime audio, video, and data between people, devices, and AI models. The SDKs, agents frameworks, and companion services are linked in the table at the bottom of this page.
LiveKit's server is written in Go, using the awesome Pion WebRTC implementation.
Important
If you're building Voice AI, LiveKit Agents is the SDK for code-first realtime voice agents. STT, LLM, TTS, turn detection, expressive speech, keyterm accuracy, tool usage, and telephony all come bundled in the framework. It's available in both Python and Node.js.
# agent.py from livekit import agents from livekit.agents import Agent, AgentServer, AgentSession, STTContextOptions, TurnHandlingOptions, inference server = AgentServer() @server.rtc_session(agent_name="my-agent") async def my_agent(ctx: agents.JobContext): session = AgentSession( stt=inference.STT(model="deepgram/nova-3", language="multi"), llm=inference.LLM(model="google/gemma-4-31b-it"), tts=inference.TTS(model="inworld/inworld-tts-2", voice="Ashley"), turn_handling=TurnHandlingOptions(turn_detection=inference.TurnDetector()), stt_context_options=STTContextOptions(keyterms=["LiveKit", "Acme Corp"]), expressive=True, ) await session.start(room=ctx.room, agent=Agent(instructions="You are a helpful voice AI assistant.")) await session.generate_reply(instructions="Greet the user and offer your assistance.") if __name__ == "__main__": agents.cli.run_app(server)Models come from LiveKit Inference with no per-provider API keys, and LiveKit Cloud handles deployment and observability. Visit the docs for more info at docs.livekit.io/agents.
Used in production by
LiveKit carries billions of calls a year for companies including Salesforce, Nvidia, Oracle, SAP, Deutsche Telekom, Spotify, Tinder, Coursera, Headspace, Skydio, Retell, Decagon, Cresta, and HeyGen. Read how Assort Health, Playback, and Polymath Robotics use it, or see more customers.
Features
- Scalable, distributed WebRTC SFU (Selective Forwarding Unit)
- People, devices, and AI agents join the same room as participants, with agent dispatch to route agents in automatically or on demand
- Modern, full-featured SDKs for web, mobile, desktop, embedded, and server
- Built for production, supports JWT authentication
- Robust networking and connectivity, UDP/TCP/TURN
- Easy to deploy: single binary, Docker or Kubernetes
- Advanced features including:
- speaker detection
- simulcast
- selective subscription
- moderation APIs
- end-to-end encryption
- SVC codecs (VP9, AV1)
- data tracks for low-latency telemetry and teleoperation
- telephony over SIP
- webhooks
- distributed and multi-region
Documentation & Guides
Working with a coding agent? Give it the LiveKit Docs MCP server, or start with the coding agents guide.
Live Demos
- Talk to a voice agent built with LiveKit Agents
- LiveKit Meet (source)
- Spatial Audio (source)
- Livestreaming from OBS Studio (source)
Install
Tip
We recommend installing LiveKit CLI along with the server. It lets you access server APIs, create tokens, generate test traffic, and scaffold and deploy agents.
The following will install LiveKit's media server:
MacOS
brew install livekit
Linux
curl -sSL https://get.livekit.io | bash
Windows
Download the latest release here
Getting Started
Starting LiveKit
Start LiveKit in development mode by running livekit-server --dev. It'll use a placeholder API key/secret pair.
API Key: devkey
API Secret: secret
To customize your setup for production, refer to our deployment docs
Creating access token
A user connecting to a LiveKit room requires an access token. Access tokens (JWT) encode the user's identity and the room permissions they've been granted. You can generate a token with our CLI:
lk token create \
--api-key devkey --api-secret secret \
--join --room my-first-room --identity user1 \
--valid-for 24h
Test with example app
Head over to our example app and enter a generated token to connect to your LiveKit server.
Once connected, your video and audio are now being published to your new LiveKit instance!
Simulating a test publisher
lk room join \
--url ws://localhost:7880 \
--api-key devkey --api-secret secret \
--identity bot-user1 \
--publish-demo \
my-first-room
This command publishes a looped demo video to a room. Due to how the video clip was encoded (keyframes every 3s), there's a slight delay before the browser has sufficient data to begin rendering frames. This is an artifact of the simulation.
Adding an agent
Agents join rooms as participants, the same way a browser or a phone does. Follow the Voice AI quickstart to build one. An agent connects to a self-hosted server the same way it connects to LiveKit Cloud; when running without Cloud, use model plugins in place of LiveKit Inference.
Deployment
Use LiveKit Cloud
LiveKit Cloud is the fastest and most reliable way to run LiveKit. It runs in 19+ regions with 99.99% uptime and adds agent hosting, model inference, telephony, and observability on top of the server. The Build plan is free, with no credit card required.
Sign up for LiveKit Cloud.
Self-host
Read our deployment docs for more information. Official Docker images and Helm charts are available.
Building from source
Pre-requisites:
- Go 1.26+ is installed
- GOPATH/bin is in your PATH
Then run
git clone https://github.com/livekit/livekit
cd livekit
./bootstrap.sh
mage
Contributing
We welcome your contributions toward improving LiveKit! Please join us on Slack or in the Developer Community to discuss your ideas and/or PRs.
License
LiveKit server is licensed under Apache License v2.0.
| LiveKit Ecosystem | |
|---|---|
| Agents SDKs | Python · Node.js |
| LiveKit SDKs | Browser · Swift · Android · Flutter · React Native · Rust · Node.js · Python · Unity · Unity (WebGL) · ESP32 · C++ |
| Starter Apps | Python Agent · TypeScript Agent · React App · SwiftUI App · Android App · Flutter App · React Native App · Web Embed |
| UI Components | React · Android Compose · SwiftUI · Flutter |
| Server APIs | Node.js · Golang · Ruby · Java/Kotlin · Python · Rust · PHP (community) · .NET (community) |
| Resources | Docs · Docs MCP Server · CLI · LiveKit Cloud |
| LiveKit Server OSS | LiveKit server · Egress · Ingress · SIP |
| Community | Developer Community · Slack · X · YouTube |