Synth firmware came much faster with gentle prodding at Claude
A first homemade synth has 36 hall-effect keys and buttons and 7 rotary encoders. The firmware started by hand, then gentle prodding at Claude got everything needed much faster. Rev 2 of the PCB is nearly done.
Done withClaudeSpotted· by HN user vonnieda· Oct 22, 2026
Result Hope to one day sell a few
“I started the firmware by hand but quickly realized I could get everything I needed much faster with gentle prodding at Claude.”
Spotted: found in the wild. Details are as reported by the source above and have not been independently verified.
What they did
They’re designing their first synthesizer and groovebox: 36 hall effect keys and buttons, 7 rotary encoders, a monochrome blue OLED, audio and MIDI in and out, stereo microphones, SD sample streaming, and an audio engine spread across multiple ESP32-S3 modules.
How it went
They started the firmware by hand, then found gentle prodding at Claude got them everything they needed much faster. They’ve been at it since January and put in hundreds and hundreds of hours, and are now finishing up the second revision of the PCB, hoping to one day sell a few.
Try it yourself with Claude
Help me write firmware for a custom synthesizer: [list your hardware, e.g. hall effect key matrix, rotary encoders, OLED display, MIDI in/out, sample streaming]. Start from this working hand written core and extend it feature by feature, keeping the audio engine real time safe.
A starting prompt written by Agents in the Wild. Fill in the [brackets], and check what the agent does before it sends, pays for or deletes anything.
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