ToolSamurai
An engineering-tools platform: 25 hardware & firmware calculators, a paid API, and an embeddable widget system.
The product
ToolSamurai is a platform, not a page of calculators: every tool is a schema-first contract — a Zod-validated manifest, a pure logic function and a test file — compiled by a registry into the website, a JSON API and embeddable widgets. Adding a tool never touches app code.
The domain depth is real engineering: a from-scratch firmware format converter (BIN ↔ Intel HEX ↔ S-record), an interactive Arduino pinout explorer, RF link budgets from the Friis equation, PCB trace width per IPC-2221, ESP32 deep-sleep battery modelling. Manifests cite the governing standard as a hard invariant.
Under the hood
THE ENGINEERING
- 01
Registry compiler validates every manifest and emits the site, JSON-Schema docs and API surface from one source of truth
- 02
Embed platform: dependency-free 186-line loader script, per-embed theming and analytics, auto-resizing iframes
- 03
587-line pure-TS Intel HEX / S-record / BIN converter with checksums and extended addressing — zero dependencies
- 04
A Postman-class API sandbox component that runs entirely client-side so the server never sees your headers
- 05
13 schema.org JSON-LD types, generated OG cards, edge canonicalisation — SEO engineered like a product
- 06
API-key system with hashed sk_ keys, rate limiting and a response envelope standard
In the product
Next case study
Diamond Machine HMI →