
Whirlsen
Developer-Focused Interface
What it does
Whirlsen is a fast, distraction-free developer utility designed to supercharge your everyday API testing and data encoding workflow. Built for developers and QA engineers who value speed over bloat, Whirlsen lets you test REST endpoints on the fly, inspect raw responses, verify HTTP status codes, and seamlessly encode or decode Base64 data. Stop wrestling with heavy desktop clients for quick checks—get the essential tools you need to build, test, and debug right in your pocket.
Does the same job
all alternatives →- IRIntercept.rest – Faster API debugging2018 · ▲89
Sharing an internal tool that accelerated my development work 10-fold, especially with API debugging. Thought fellow developers here might find it useful. As a developer, I often have trouble reproducing errors at the client end. https://intercept.rest lets me debug and monitor API requests and responses. It is similar to the Network tab in Chrome Developer Tools but works for any API: mobile apps, webhooks, frontend etc. After I shared it with a close circle of friends, they found it incredibly useful and even found new use cases, I never imagined. Been a long time lurker here and…





More dev tools this month
the category →



Open-source GTM skills for technical founders
Dev tools · 29d ago · gtmcofounder.com

OpenTrailPaper is open-source bike computer firmware for the LilyGO T5S3 4.7" E-Paper PRO. It supports offline maps, GPX routes, FIT recording and Bluetooth sensors.
Dev tools · 2d ago · opentrailpaper.com

Launched alongside, August 2026
the whole month →- TL
Life & fun · 10d ago · louisabraham.github.io


- SA
Hello HN! I found that picking out plausible but diverse skin tones for my digital art and game development projects was kind of difficult, and I got curious about if there was a way to define a color space that made it easy. I've built a color picker and procedural generation algorithm based on the space as well as a bunch of other fun js features and demos throughout the page that use the equations. If you find it interesting, I have lots of explanations of how I built it and what properties the space has. The methodology might be a bit shaky, but hopefully the result is as helpful for…
Life & fun · Aug 2026 · toneyalexander.github.io


I trained a 125M-parameter transformer to autocomplete piano performances in real time (~108 notes/sec on an iPhone 15). The idea is basically GitHub Copilot or Tabnine, except instead of prompting it with code, you prompt it by playing a few notes on a MIDI piano. The model then continues what you played, entirely on-device. The app is free if anyone wants to try it. Happy to answer questions about the model, training, Core ML, or the many things that didn't work.
AI · 17d ago · simedw.com