Three days is enough time to build a real product when the loop is small, the managed services are deliberate, and every feature proves the central idea.
Find the smallest complete loop
For Yappper, the loop was simple: create a prompt, collect a spoken response, store the audio, transcribe it, and make the result useful to the survey owner.
That scope kept the experience coherent. Extra surface area would have produced more screens but less proof.
Buy time with managed services
Gemini handled speech-to-text transcription, Supabase stored audio and text, Clerk handled authentication, and Polar handled payments. Each service replaced work that was necessary but not differentiating.
The integration boundaries still mattered. A hackathon deadline is a reason to keep those boundaries clear because there is little time to debug hidden coupling.
Polish is part of the prototype
Yappper was selected as one of ten winners in the Raenest × DevCareer hackathon. The result reinforced a principle I use in client work too: finish the full user journey before widening the feature list.
