OpenProsperity Visualizer

A local-first, open-source dashboard for the IMC Prosperity algorithmic trading competition. Drop in your backtest .log files and get a fast, information-dense view of what your algorithm actually did — and crucially, load N variants at once to compare them side-by-side.

Your strategy never leaves your laptop. No uploads, no accounts, no telemetry.

Pure HTML, CSS, and vanilla JavaScript — no framework, no build step.

Why another visualizer?

jmerle's imc-prosperity-3-visualizer set the bar for what a static-SPA Prosperity tool should look like, and much of OpenProsperity is downstream of that prior art. We emphasize:

• Multi-strategy comparison as the default mental model. Loading 2–10 log files at once is a first-class flow. Diff mode plots variant − baseline on the PnL chart. Normalized-x mode lets you compare a 1k-tick preview against a 10k-tick full day on the same axis.
• Local-first, proven. Open the devtools network tab and confirm nothing leaves the browser. The only outbound request is for the static HTML / JS / CSS bundle.
• Zero dependencies at runtime. No React, no Tailwind, no npm packages in the shipped site — just browser APIs. Clone and serve any HTTP server.

Quick start

git clone https://github.com/lachy-dauth/prosperity-visualizer
cd prosperity-visualizer

# Serve the directory with any static HTTP server. Examples:
python3 -m http.server 8080
# or
npx serve .

Open http://localhost:8080 and drop any .log file from IMC's submission dashboard (or from prosperity3bt) into the left rail.

A plain file:// open will not work because the app uses a Web Worker and fetch() for the demo log. You need an HTTP server.

Deploy to GitHub Pages

This repo ships with a ready-to-go Pages workflow at .github/workflows/deploy.yml. It publishes the repo root as-is (no build).

1. Settings → Pages → Build and deployment → Source: GitHub Actions.
2. Push to main (or run the workflow manually from the Actions tab).

Features

• Drop 1–N log files; each gets a color and appears in all comparison charts.
• Playback controls with variable speed (1×/5×/10×/20×/50×), scrubber, keyboard shortcuts (Space / ←→ / Shift+←→).
• KPI cards, PnL performance chart, per-product price & liquidity chart, position chart with limit bands, live order book, pressure gauge, own-fills table, and sandbox/algorithm/trader-data log tabs — all synchronized.
• Decodes jmerle-style base64 lambdaLog dumps automatically; falls back gracefully when your algo just uses print().
• Export: PnL chart → PNG, comparison summary → CSV.
• Optional "Save to browser" toggle persists parsed strategies to IndexedDB across reloads. Off by default.

Data handling (read this)

1. Your file is read client-side with the File API and parsed in a Web Worker.
2. Parsed data lives only in JavaScript memory for the tab. Refresh the tab and it's gone, unless you opted in to IndexedDB persistence.
3. No network requests are made with the contents of your log.
4. No analytics, no cookies, no Google-anything.

Project layout

index.html            # Entry HTML
styles.css            # All styles (custom variables, dark/light)
app.js                # Top-level wiring
favicon.svg
demo.log              # Bundled sample log for first-time visitors
js/
  store.js            # Tiny pub/sub store + prefs
  parser.js           # CSV + strategy builder (multi-day safe)
  worker.js           # Parser Web Worker entry
  parserClient.js     # Main-thread worker client
  persistence.js      # Native IndexedDB
  chart.js            # Vanilla Canvas line chart
  downsample.js       # LTTB downsampling
  colors.js           # Strategy palette
  format.js           # Number formatters
  positionLimits.js   # Known IMC limits per season
  exporters.js        # CSV + PNG download
  demoLog.js          # Bundled demo fetch
  uid.js              # Id generator
  panels/
    rail.js  topBar.js  kpi.js
    pnlChart.js  priceChart.js  positionChart.js
    summary.js  orderBook.js  pressure.js
    ownFills.js  logs.js  about.js

Adding a new Prosperity season

Product names and position limits change every year. Edit js/positionLimits.js and add the new symbols. Nothing else should need touching unless IMC changes the log schema.

Credits

• Inspired by jmerle/imc-prosperity-3-visualizer.
• IMC Prosperity is © IMC Trading; this project is an independent fan tool.

License

MIT — see LICENSE.