A visual circuit editor and audio effects simulator that runs entirely in your browser. Draw a schematic, drop in a guitar sample, and hear what it sounds like through the simulated circuit — no install, no server, no SPICE setup.
Solder compiles your schematic to a SPICE netlist and runs it through ngspice compiled to WebAssembly. It is intentionally small-scoped: analog audio circuits like guitar pedals, EQs, and clipping stages.
pnpm install
pnpm devOpen http://localhost:5173. A modern browser with WebAssembly and SharedArrayBuffer is required — the dev server sets the Cross-Origin Isolation headers ngspice needs to work.
When the editor loads, click Examples in the toolbar to load a starter circuit, then Simulate to hear it.
- Schematic editor — drop components, drag connections, multi-tab circuits, undo/redo, JSON import/export. KiCad-style power pins and global net labels keep wiring tidy.
- Place-symbol command bar — press
ato search the full component catalog (resistors, capacitors, op-amps, diodes, BJTs, JFETs, MOSFETs, potentiometers, etc.) with KiCad-style recent-items at the top. - Simulate audio — use one of the bundled samples, upload your own WAV, or fall back to a SIN test tone. Select a region of the input waveform to simulate only a portion. Hear input and output, or scrub the overlay to see how the circuit shapes the signal.
- Bundled examples — filters, gain stages, clipping circuits, plus three complete pedals (ProCo RAT, MXR Distortion+, Fuzz Face). Each ships with inline notes explaining what every section does. See
docs/examples.md.
| Shortcut | Action |
|---|---|
a |
Open the place-symbol command bar |
r / Shift+R |
Rotate selection 90° clockwise / counter-clockwise |
⌘/Ctrl+Z |
Undo |
⌘/Ctrl+Shift+Z |
Redo |
? or / |
Open the in-app keyboard reference |
Full list: docs/keyboard-shortcuts.md. Press ? in the editor for the same reference as a modal.
User-facing:
docs/examples.md— tour of the bundled circuits and pedals, and what each one teaches.docs/keyboard-shortcuts.md— full shortcut list.
Contributor-facing:
AGENTS.md— entry point for anyone (or any agent) working on the codebase. Routes to everything below.docs/architecture.md— Zustand store layout, slices, hooks, data flow.docs/component-library.md— howsrc/lib/models/is organized; the three places you have to register a new component.docs/simulation.md— netlist compiler and the ngspice/eecircuit-engine quirks that will silently break things if you ignore them.docs/audio.md—AudioPipeline, browser autoplay policy, IndexedDB sample persistence.docs/ui-patterns.md— palette catalog, global hotkey gating, modal opt-in, example circuit conventions.docs/code-style.md— early returns, block comments, file organization, typography.
pnpm dev # Start dev server with HMR
pnpm build # TypeScript compile + production build
pnpm preview # Preview production build locally
pnpm lint # Lint with Biome
pnpm test # Run all tests (vitest)
pnpm test:ui # Run tests with interactive Vitest UIReact 19, TypeScript, Vite, XYFlow for the canvas, Zustand for state, Tailwind CSS, Biome for lint + format, and ngspice via eecircuit-engine running in a Web Worker. See docs/architecture.md for how everything fits together.