ETHGlobal Buenos Aires: 36-Hour Hackathon with Record Prize Pool

General
1

ETHGlobal’s final hackathon of 2025 runs November 21-23 at La Rural alongside Devconnect. This is going to be massive.

Key Details:

  • $500,000 USD in prizes - Record pool for ETHGlobal
  • 36-hour build time
  • Teams up to 5 people
  • Submission deadline: Sunday, November 23rd at 09:00 AM UTC-3

Requirements:

  • Stake a small amount of ETH to participate (returned on project submission)
  • All projects must be created entirely during the hackathon
  • Public libraries and boilerplate OK, but no pre-existing project-specific code

What You Get:

  • Experienced mentors from top protocols
  • Cutting-edge tooling and SDKs
  • Workshops throughout the event
  • Direct access to sponsor teams

Notable Speakers at Devconnect (potential judges):
Vitalik Buterin, Tomasz Stanczak, Stani Kulechov, Jesse Pollak, Danny Ryan, Linda Xie

Who’s forming teams? What are you planning to build?

2

I’ve mentored at 5 ETHGlobal events. Here’s what separates winners from the rest:

1. Scope ruthlessly
36 hours disappears fast. Build ONE thing well, not three things poorly. Judges want to see a working demo, not a pitch deck for what you’d build with more time.

2. Pick sponsor bounties strategically
Don’t just chase the biggest prizes. Look for bounties with fewer submissions. A $5K bounty with 10 submissions beats a $50K bounty with 500.

3. Start with the demo
Build your demo flow first, then fill in the functionality. Nothing worse than great code that crashes during judging.

4. Use templates
Scaffold-ETH, Create-Web3-Dapp, RainbowKit starters - don’t waste hours on boilerplate.

5. Sleep (a little)
I’ve seen teams flame out at hour 30 because they pulled all-nighters. Rotate rest shifts.

6. Practice your pitch
You get 3-5 minutes with judges. Practice until it’s tight.

For teams using BlockEden: set up your RPC endpoints BEFORE the hackathon starts. Don’t waste build time on infrastructure setup.

3

BlockEden will be supporting hackathon builders! Here’s what we’re offering:

Free tier upgrades during the event:

  • Higher rate limits for hackathon participants
  • Access to archive nodes for historical queries
  • Multi-chain support (Ethereum, Polygon, Arbitrum, Base, Optimism)

Why RPC matters for your hackathon project:

  1. Reliability - Public RPCs rate-limit aggressively. Nothing kills a demo like “429 Too Many Requests”

  2. Speed - Low latency matters for real-time UX. Our Buenos Aires presence helps.

  3. Archive access - If you’re building analytics, indexing, or historical queries, you need archive nodes

  4. WebSocket support - For real-time subscriptions and event listening

Setup guide:

  1. Create BlockEden account before the hackathon
  2. Generate API keys for chains you’ll use
  3. Set up environment variables in your project template
  4. Test connections before Nov 21

We’ll have team members on-site for support. Look for BlockEden shirts!

DM us for hackathon promo codes.

4

Won a bounty at ETHGlobal Istanbul last year. Adding to @mentor_valeria’s advice:

What actually won:
We built a simple tool that solved a real pain point for developers. Nothing fancy - just useful. Judges see hundreds of “AI + blockchain + NFT” projects. Useful and working beats ambitious and broken.

Team composition that worked:

  • 2 solidity devs
  • 1 frontend dev
  • 1 designer (yes, design matters)
  • 1 floater (helped everywhere, handled submissions)

Sponsor bounty strategy:
We talked to sponsor reps FIRST. Asked what they actually wanted to see. Many bounties have unofficial criteria - they’re looking for specific integrations or use cases. Get that intel.

Common mistakes I saw:

  • Teams building in silos, not integrating until hour 30
  • No version control (yes, really)
  • Deploying to mainnet with bugs (use testnets!)
  • Forgetting to record a video backup (WiFi always fails during demos)

My plan for Buenos Aires:
Building something with account abstraction (EIP-7702). Post-Pectra capabilities aren’t fully explored yet - opportunity for novel UX.

Looking for a frontend dev if anyone’s interested!

5

This is shaping up to be the best ETHGlobal yet. $500K prizes + Devconnect context = serious talent showing up.

@mentor_valeria Excellent point on sponsor bounties. I’d add: attend sponsor workshops on Nov 20-21 (before hackathon starts). You’ll understand their tech better AND make face-time with judges.

@infra_team Thanks for the BlockEden support! Archive node access is clutch for analytics projects. Will DM for promo codes.

@winner_mateo Account abstraction is smart. With EIP-7702 live since May, there’s still greenfield for hackathon projects. Ideas I’m seeing:

  • Gasless onboarding flows
  • Session keys for gaming
  • Social recovery implementations
  • Batch transaction UX

Hot themes I expect to see:

  1. AI agents with wallets - Autonomous agents that can transact
  2. zkTLS integrations - Building on what’s discussed Nov 19
  3. Cross-L2 UX - Abstracting away chain complexity
  4. Argentina-specific solutions - Stablecoin UX for local context

The Argentina angle is underrated. Build something locals would actually use and you’ll stand out.

See everyone Nov 21! :argentina: