Where onchain founders
start their journey
Harenix hackathons are global, online competitions where founders sprint for six weeks to build products that bring markets onchain. Founders treat them as the first chapter of a company.
Compete
Harenix hosts two world's fairs a year, one in spring and one in fall. The Harenix World's Fair runs from September 29 to November 9, 2026.
Win
The Harenix team and pavilion judges review every exhibit. Winners share $420,000 in USDG and recognition across the Robinhood Chain ecosystem.
Get funded
Selected winners join the Harenix Accelerator in New York and receive $150,000 from the Harenix fund.
Every fair tells its own story
Each fair brings its own campaign, pavilions and builders. This one opens the first chapter.
Harenix World's Fair
Eight pavilions on Robinhood Chain, $420,000 in prizes and $1.5 million in seed funding. Submissions close November 9, 2026.
Enter the World's FairNext up: Spring 2027, announced after this fair's winners.
Registration opens
Sign in, build a profile, form teams.
The fair opens
Kickoff stream on X. Work from this date counts.
Submissions close
The Arena locks every exhibit.
Winners crowned
Accelerator teams announced the same day.
Interested in sponsoring the fair?
Protocols, funds and infrastructure teams host pavilions, judge exhibits and offer credits to builders. Tell us what you want to see built.
Get in touchEarn your place
The best builders come back, level up and claim a place among the best on Robinhood Chain. The hall of winners opens on December 7, 2026. Until then, browse the exhibits teams have already submitted.
See the exhibitsWhat the judges score
After the deadline the team runs several review rounds, sends a shortlist to the judges and invites a smaller group to a 15-minute video interview.
Founder and market fit
Why this team, and why does it care enough about this problem to keep going after December?
Insight
What do you know about tokenized equities, payments or onchain markets that others miss?
Product and execution
How well it works, how it compares with alternatives and how fast you ship fixes after feedback.
Use of Robinhood Chain
Stock Tokens, USDG, oracles and account abstraction used where they matter.
Market size
A large market today, or a small one growing fast enough to become large.
Communication
A pitch video that explains the product in three minutes and makes a stranger want to try it.
Viability and traction
A path to a sustainable business. Users or revenue before the deadline count in your favor.
Ready to build?
Find cofounders in the Builders directory, deploy to Robinhood Chain and exhibit your product at the fair.
Frequently Asked Questions
Do I have to build on Robinhood Chain?
Yes. Every submission needs at least one contract deployed on Robinhood Chain mainnet or testnet, and the Arena verifies it by reading its bytecode. You can use other chains alongside it, for example to bridge liquidity in or settle elsewhere, but judges look at the Robinhood Chain part first.
What is Harenix?
Harenix runs online hackathons for startups building on Robinhood Chain, staged as world's fairs. We host two fairs a year. Each one gives founders six weeks to build, judges who review the exhibits and an accelerator for the best teams.
The format suits people who want to start a company. If you only want to learn Solidity for a weekend, the resources page will serve you better than the competition.
How do I register and submit?
Open the Arena, connect a wallet and sign one message. Fill in your profile, then create a team or join one with an invite code. Every teammate signs in with their own wallet.
Any member can edit the project. Only the team leader can press submit. Each builder belongs to one team, and each team submits one project.
Can I start from existing code?
You can, but judges score only the work you complete between September 29 and November 9. Disclose earlier work in your project description.
If a team hides its development history, Harenix may disqualify the team, ban its members from future fairs and revoke prizes. Open-source libraries and protocols written by other people don't count as prior work. Compose with them freely.
Who is eligible to win?
- New products that haven't raised a priced equity round or a token sale.
- Founders and developers aged 18 or older, anywhere our payout partners can legally send funds.
- For the University Prize, every team member must be enrolled at a university during the build window.
What goes into a submission?
Think of the submission as a pitch to an investor. The Arena asks for:
- Project name, tagline, pavilion and a description of up to 2,000 characters.
- A contract address on Robinhood Chain that the Arena verifies.
- A GitHub repository. Private repos work if you grant read access to builders@harenix.fun.
- A pitch video of three minutes or less. Judges watch it first.
- A live demo link if you have one, and weekly updates if you want the panel to see momentum.
What do judges look for in the repository?
We want to see that your team did substantial work during the build window, that you wrote it yourselves and that you picked the right features to build first.
We don't grade language choice, framework or code style. Ship what works for your product.
Are weekly updates required?
No. Teams that post them give judges context before interviews, so we recommend one each week: a few sentences on what shipped, what broke and what comes next, plus an optional link.
Can I compete solo?
Yes. A team of one works. Most funded startups have two or three founders who split product and distribution, so check the Builders directory for people who want a team.
Do I need to be technical?
No. Many technical builders want a partner who handles growth, design or business development. Founders also ship credible prototypes with AI coding tools. Over time you will want a technical cofounder, because judges score execution.
How and when do winners get paid?
We name winners on December 7, 2026. Each winning team completes a short identity check, then receives USDG on Robinhood Chain at the wallets it lists. Accelerator investments follow a separate SAFE agreement signed before the program starts.
If I win, do I have to join the Accelerator?
No. Prize money is yours either way. Selected teams that want to keep building full time can accept the $150,000 investment and the ten-week program in New York. See the Accelerator page.
What is $HRNX and do I need it?
$HRNX is the Harenix community token and it launches on Robinhood Chain soon. You don't need it to register, compete or win. We will publish the contract address on @harenix and on this site at the same moment. Any address you see before then is fake.
Where can I ask technical questions?
Join the weekly live sessions on X, where the team answers questions at the end. For account problems, email builders@harenix.fun from the address you want us to reply to.
Will every team get feedback?
We can't write individual feedback for every submission. Our team reviews every project that meets the requirements, and the public Exhibits gallery shows community votes in real time.
What is the code of conduct?
- Be respectful. Criticize products, never people.
- Be professional. No harassment, discrimination, sexual content or intimidation in any Harenix space, including X replies and live sessions.
- Be honest. Disclose prior work, don't copy other teams and don't fake traction or votes. We remove votes from wallets that look automated.
- Be open. Builders join from every background and country. Help people who are newer than you.
Harenix may disqualify anyone who breaks these rules. The official rules hold the full text.
No questions match. Email builders@harenix.fun and we will answer.