I built a toy music controller for my 5yo with a coding agent
The HN community may find the context of the prompts, organized by each turn in each session, the most useful. See the website/docs/prompts.md and session-X.md files. I also started exploring some workflows for the LLM to execute, organized in the website/docs/tasks/ folder. I found it pretty handy to have the LLM document our work as we went and simply embedded the static site into the executable, along with all the music and logic. The whole project took me about a day for the backend. The C++ controller itself took only a few turns. I enjoyed focusing on my son's…
I built a toy music controller for my 5yo with a coding agent launched on July 8, 2025 with 37 votes, #625 of 9,223 launches that month and more than 90% of that year's launches.
In plain words
A developer built a toy music controller for a five-year-old using a coding agent to handle the implementation. The project includes a C++ controller, embedded static documentation, and music playback logic, completed in about a day. The maker used an LLM agent to generate code in C++, JavaScript, and Go while focusing on the user experience, and documented the prompts and development workflow for others exploring AI-assisted development.
written from the facts on this page · September 2026
From the sources
In the maker’s words, at launch
The HN community may find the context of the prompts, organized by each turn in each session, the most useful. See the website/docs/prompts.md and session-X.md files. I also started exploring some workflows for the LLM to execute, organized in the website/docs/tasks/ folder. I found it pretty…
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