Hack the Stackathon is a one-day stress test for builders
Y Combinator’s Hack the Stackathon is emerging as one of the community-driven events where builders, hackers, and entrepreneurs come together to rapid-prototype ideas and push tech boundaries in a time-bound environment. It is part of a larger culture of hackathons hosted or supported by Y Combinator, where the goal is to encourage creativity, learning, and real project building. Y Combinator
Hackathons are intense collaborative programming events where teams work together to build functioning software or hardware over a short period, often 24 to 48 hours. These events help participants sharpen skills like problem solving, teamwork, and rapid prototyping, and sometimes lead to ongoing projects or even startup formation.
From YC Event Page
Hack the Stackathon is a one-day stress test for builders who want to ship real AI-powered systems, not demos.
This is not a demo day hackathon.
We are not optimizing for polished UIs, slide decks, or pitch theatrics.
We care about what you tried to build, what broke, and what actually shipped.
Building real AI applications is hard, not because of the models, but because of everything around them. Scraping websites. Parsing documents. Communicating with users. Each problem is a rabbit hole of edge cases, infrastructure, and wasted engineering time.
That’s why we built our companies.
Together, we provide the infrastructure layer for modern AI applications:
- Firecrawl: Crawl and extract structured data from any website
- Reducto: Parse, extract from, and fill-out documents using vision-based AI
- Resend: Send and receive emails that actually reach the inbox
We handle the infrastructure.
You build the product.
Ship it in a day.
Join builders from the AI and infrastructure worlds to hack on the next generation of data-powered applications. Systems that can ingest, structure, and act on information from anywhere.
What You'll Do:
- Build a real, working system using modern data and AI infrastructure
- Get hands-on help from the engineers building Firecrawl, Reducto, and Resend
- Demo what you actually built to experienced founders and operators, with a focus on technical decisions, tradeoffs, and what broke
What You'll Build:
Projects that combine AI with the modern developer stack.
We’re most excited about systems that ingest real data, transform it, and take action.
- **Deep research agents
**Crawl the web, parse cited documents, and deliver structured daily briefings via email - **Invoice and document pipelines
**Extract line items from PDFs, enrich vendor data from the web, and trigger downstream workflows - **Competitive intelligence systems
**Monitor websites and press releases, detect changes, and alert teams in real time - **AI-powered legal tooling
**Parse contracts, research case law, and generate summaries you’d actually trust - **Lead enrichment and outreach engines
**Scrape company sites, extract structured data from documents, and power automated communication
Prizes include:
- Guaranteed Y Combinator Interview
- $25,000+ in Cash Prizes
- 1,500,000+ in Credits Prizes
- Exclusive office visits, limited edition swag, and more.
Sponsors
Firecrawl, Reducto , Resend, MongoDB, Open Router, Supabase , Eleven Labs, and Lovable
Schedule
Overview
- 08:00 AM to 09:30 AM Registration + Breakfast
- 09:30 AM to 10:00 AM Kickoff + Ground Rules
- 10:00 AM to 12:30 PM Team Formation + Hacking Begins
- 12:30 PM Lunch Served
- 01:00 PM to 02:45 PM Live Demos + Optional Deep Dives*
- 05:15 PM Dinner Served
- 06:15 PM Hard Submission Deadline
- 06:00 PM to 07:30 PM Judging + Demos
- 07:30 PM to 08:00 PM Winners Announced + Closing
*Hacking is welcome to continue throughout this block
Who Should Apply
This event is for builders who want to spend a full day shipping something real.
You should apply if you:
- Build with LLMs, APIs, or modern backend systems
- Care more about making something work than making it look good
- Are curious about web data, document pipelines, and communication infrastructure
- Want to stress-test an idea you’ve been meaning to build
You don’t need to be an expert in every part of the stack.
You do need to be curious, ambitious, and willing to ship.
Participation is free but selective. Space is limited.
Why Join
- Spend a day building at Y Combinator HQ alongside serious builders in AI and data
- Get direct feedback from engineers who ship and operate real infrastructure
- Stress-test an idea and see how far it gets in a single day
- Compete for prizes and follow-on opportunities that can meaningfully change what you work on next
What Every Builder Gets:
Every participant walks away with:
- **Firecrawl Hobby Plan
**One month of free access to start building with real web data - 200 Lovable Credits
Use the vibe-coding tool to prototype, experiment, and ship fast - **All meals covered
**Breakfast, lunch, dinner, snacks, and drinks so you never have to context-switch - **Thoughtful swag
**Limited-run items from Firecrawl, Reducto, and Resend, plus select sponsors
What Hackathons Like This Look Like
In general, hackathons are known for their fast pace and collaborative energy. Participants usually form teams, brainstorm ideas, divide tasks, and work through the night to build something real. Whether the theme is AI agents, mobile apps, or hardware hacks, the objective stays the same: build and demo something working in a short span.
Being part of an event supported by YC means you get visibility from one of the most influential early stage communities in tech. Y Combinator has helped launch companies like Airbnb, Dropbox, and Stripe by focusing on solving real problems and building products that users want.
In a YC-centric hackathon environment, winners often get more than prizes. They get access to connections, feedback from mentors, and even opportunities to interview for future YC batches. That makes events like Hack the Stackathon appealing not only to students and hobbyists but to early founders and creators who want to get mentorship and exposure.
Why These Events Still Matter
Hackathon culture can sometimes feel intense and chaotic, but it does more than produce quick hacks. Events like Hack the Stackathon encourage a mindset of rapid execution, learning by doing, and experimenting with ideas you might otherwise postpone.
Even if your hack doesn’t win a prize, what you build - or even just the skills you sharpen - can lead to future projects, collaborators, or products that actually ship to users. That’s one of the reasons hackathons remain relevant in tech, and why YC and others keep hosting them.
Final Thoughts
If you are someone who enjoys building in short bursts, hacking together prototypes, and pushing your limits, events like Hack the Stackathon are worth exploring. They give you a focused environment to turn ideas into working demos, meet like-minded creators, and potentially get feedback from experienced builders in the Y Combinator ecosystem.
Keep an eye on the official Y Combinator events page and YC community channels for specific dates, themes, and registration details so you can join the next run and bring your next idea to life in a weekend sprint.
