Prism

Prism is a visualization library for .pulse files. It compiles declarative JSON specs into charts — server-side SVG/PNG/PDF via Go, and live in-browser via web components — using Vega-Lite-inspired vocabulary with snake_case naming and Pulse expression syntax.

Install

go install github.com/frankbardon/prism/cmd/prism@latest

60-second tour

prism init                          # writes .prism/ with schemas + examples
prism plot .prism/examples/bar_basic.json > bar.svg
prism plot --theme=dark bar.json > bar-dark.svg
prism serve --addr :8080            # Twirp + /prism/scene endpoint
prism mcp                            # MCP server over stdio

Try it now

• Interactive Playground — edit a spec and see it render live, entirely in your browser via WASM. ~25 curated examples covering marks, composition, transforms, and themes.

Where to go next

• Getting started — install, first chart, editor setup.
• Playground — live spec editor (WASM, no install).
• Gallery — 59 fixture specs with rendered SVGs.
• Concepts — Spec, marks, encoding, composition, selections, themes, multi-source.
• Reference — spec field reference + error code catalog.
• Cookbook — recipes for common patterns.
• Migration from Vega-Lite.