Building Matchstick Events: Real-Time Market Event Streaming

Indie traders need real-time SEC filings, earnings, and news, but most platforms are expensive, closed, or hard to self-host. I wanted a streaming system that anyone could run locally with a simple dashboard and a reliable replay model.

The Problem

Existing solutions are:

  • Expensive and vendor locked
  • Hard to integrate without heavy frameworks
  • Missing replay for late-joining clients
  • Limited filtering for symbols and keywords

The Solution

Matchstick Events is an open-source market events API that streams SEC filings and financial news via Server-Sent Events (SSE), with snapshot and replay support.

Key Features

  • Real-time SSE streaming with auto reconnect
  • Symbol and keyword filtering
  • Snapshot + diff replay for late-joining clients
  • Self-hostable with a no-build dashboard

Technical Highlights

Sources (EDGAR, RSS)
  -> Adapters
  -> EventBus
  -> Snapshot + Diff
  -> SSE Stream
  -> Datastar UI
  • Native Node.js http for full SSE control
  • EventEmitter3 for the event bus
  • LRU cache for bounded memory
  • Datastar UI with no build step
  • Snapshot + diff model inspired by Matchstick TTE

Impact

  • Late-joining clients can replay full event history
  • Events arrive within ~200ms of ingestion
  • Dashboard runs without React or build tooling

What Makes It Different

Most market event APIs are built for enterprise terminals. Matchstick Events is built for indie traders who need self-hosted, transparent tooling with fast streaming and replay.

Tech Stack

  • Node.js (native http)
  • EventEmitter3
  • Datastar UI
  • Docker-ready deployment

Current Status

v0.1.0 Operational:

  • SEC EDGAR adapter
  • Financial news RSS adapter
  • Snapshot + replay system
  • Tauri desktop wrapper

What I Learned

SSE is ideal for streaming workloads when you keep the server simple and the client resilient. Snapshot + diff replay makes the system usable for late-joining clients without requiring stateful websockets.

Links

Real-time market events without the vendor lock-in.