Developer builds tool to auto-compile all hackathon submissions using disposable cloud VMs

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A developer and hackathon organizer identified a long-standing blind spot in hackathon judging: with 40–80 teams and only minutes per project, judges almost never verify whether submitted code actually builds. Evaluation has historically relied on live demos and pitches, which test a team's ability to describe software rather than build it. To address this, the developer used Fly.io's Sprites API — which spins up disposable Linux machines billed by the second — to create an automated tool that clones each submitted repository, detects the project type, installs dependencies, compiles the code, and runs any existing tests. The tool can process submissions in parallel and logs exactly how far each build progresses, making it feasible to check all entries before judging begins. The experiment, run across 164 submissions, suggests that systematic build verification at hackathons is now a practical option rather than a logistical impossibility.

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