HackerRank's 24-hour online hackathon series where you build and ship an AI agent, then defend it to an AI judge. Free, solo and open worldwide. Next edition: 24 Oct 2026.
24 Oct 2026 · Closed · $2,400 cash + Codex credits for the top 3 Codex builders
12 Sept 2026 · Closed · $1,200 cash (1st), $300 each (2nd-5th), Codex credits for the top 3 Codex builders
1 Aug 2026 · Closed · Claude Max 5x: 1 year for 1st (about $1,200), 3 months each for 2nd-5th (about $300)
19 Jun 2026 · Closed · Claude Max 5x: 1 year for 1st (about $1,200), 3 months each for 2nd-5th (about $300)
1 May 2026 · Closed · $1,000+ in AI tools (1st), $150+ in Granola credits (2nd-5th)