Testing
Testing real-time event-driven code is one of the more intellectually demanding corners of frontend and Node.js testing. The code is inherently asynchronous, order-dependent, and timing-sensitive. Standard expect(value).toBe(x) assertions are insufficient when the value hasn't arrived yet. This guide covers the
Supabase
Supabase Realtime sits on top of Phoenix Channels over WebSocket. Testing it means dealing with asynchronous event delivery, connection lifecycle (SUBSCRIBED, CHANNEL_ERROR, CLOSED), and timing-sensitive state — exactly the conditions that produce flaky tests. This guide covers unit testing with a mocked Realtime client, integration testing postgres_changes events
Testing
Liveblocks powers real-time collaboration features in products like Figma-style editors, multiplayer forms, live cursors, and shared document systems. Its combination of presence (who's online, where are their cursors), storage (conflict-free shared state), and comments makes it a compelling choice—but also a challenging one to
Testing
Socket.io applications require testing at three layers: the HTTP upgrade handshake, the event protocol layer (emit/on, ACKs, rooms), and real concurrency behavior under load. This guide covers in-process test setup, Jest event testing, middleware mocking, and scalable load patterns. Socket.io is the de-facto standard for
Testing
WebRTC applications are notoriously hard to test because they involve browser APIs, network negotiation, and real-time media. This guide covers mocking RTCPeerConnection in Jest, intercepting WebRTC in Playwright, measuring media quality with getStats(), and simulating adverse network conditions. WebRTC powers video calls, screen sharing, and peer-to-peer data