Database
Your data layer. Pick once and don't look back.
The database decision shapes everything else — your queries, your auth, your realtime features, your deployment. Most hackathon teams overthink this. You don't need a distributed database. You need something that's live, has a free tier, and lets you write SQL or call an ORM without fighting it.
Don't pick a database that requires you to manage infrastructure during the hackathon. Don't use multiple databases. Don't add an ORM if you're already comfortable with raw SQL in your provider's client.
Supabase if you want Postgres + auth + realtime + storage all in one. Neon if you just want serverless Postgres. PlanetScale if you're on MySQL. Add Prisma or Drizzle ORM only if you're doing complex relational logic that benefits from type safety.