Best Developer Bounty Programs in 2026:
Earn Crypto Building Open Source Tools

HackerOne is the world's largest bug bounty platform, connecting ethical hackers with organizations including the U.S. Department of Defense, Google, Microsoft, and Goldman Sachs. The platform has paid out over $300 million in total bounties to security researchers since its founding in 2012. In the most recent annual report (October 2025), HackerOne paid $81 million in rewards over the preceding 12 months, a 13% year-over-year increase. Six researchers have each earned over $1 million on the platform.

Best for: Developers with web application security experience, penetration testing skills, and knowledge of OWASP Top 10 vulnerabilities. Payments are primarily in USD via PayPal, bank transfer, or Bitcoin. The platform is not crypto-native but accepts cryptocurrency for some programs.

Immunefi is the dominant bug bounty platform for DeFi and smart contract security. The platform has paid out over $100 million to ethical hackers since launch, protecting over $190 billion in user funds across 330+ projects including Chainlink, MakerDAO, Wormhole, and SushiSwap. Smart contract bugs account for 77.5% ($78 million) of all payouts. Critical severity bugs account for 87.8% ($88 million) of the total.

The payout ceiling on Immunefi is extraordinary. Individual bounties for critical vulnerabilities in major protocols can reach $10 million. Even lower-severity findings regularly pay $1,000-$50,000. Payments are made in USDC, ETH, or project-specific tokens depending on the protocol's program.

Best for: Developers with deep Solidity/Vyper expertise and smart contract security experience. Understanding of DeFi mechanics (AMMs, lending protocols, bridges) is essential. This is the highest-paying bounty category but requires the most specialized knowledge.

Code4rena operates a unique competitive audit model. Protocols submit their smart contract code to a time-boxed contest (typically 3-7 days), and a community of security researchers called "Wardens" compete to find vulnerabilities. Prize pools are divided among wardens who find valid bugs, with higher severity findings earning proportionally larger shares. Individual contest prize pools range from $10,000 to $200,000+.

Code4rena was acquired by Zellic in 2024 but continues operating independently. The competitive format means earnings are not guaranteed. A top warden finding a solo high-severity bug in a $100K contest might earn $30,000-$50,000, while a warden who duplicates findings already submitted by others earns far less. Payouts are in USDC.

Gitcoin launched in 2017 as a bounty platform for Ethereum open source development and has since evolved into the most important funding mechanism in crypto open source. Through its Grants program, Gitcoin has distributed over $60 million to early-stage builders working on DeFi, public goods, climate, and developer tooling. Gitcoin pioneered quadratic funding, a mechanism where small community donations are amplified by matching pools from larger sponsors, ensuring that projects with broad community support receive proportionally more funding.

The platform operates in two modes. Gitcoin Grants rounds are periodic funding events where projects apply for matching funds and community members donate. The quadratic funding formula amplifies small donations: a project receiving $1 from 1,000 people gets more matching funds than a project receiving $1,000 from one person. Gitcoin Bounties (bounties.gitcoin.co) are task-specific payments where project maintainers post issues with ETH or DAI rewards attached. Payments are made in ETH, DAI, and various ERC-20 tokens.

Best for: Full-stack developers contributing to Ethereum and crypto open source tooling. If you are building developer tools, public goods infrastructure, or ecosystem utilities, Gitcoin Grants rounds are the primary funding mechanism. Individual bounties range from $100 to $50,000+ depending on scope and sponsor.

Optimism's Retroactive Public Goods Funding (RetroPGF) is one of the most innovative funding mechanisms in crypto. Unlike traditional grants where you apply before building, RetroPGF rewards work that has already been done and has already demonstrated impact. The core principle is "impact = profit": if your work is deemed valuable to the Optimism ecosystem, you receive retroactive compensation.

Four completed funding rounds have collectively allocated over $100 million in OP tokens, with an additional $1.3 billion reserved for future rounds. In 2025, Optimism transitioned from annual mega-rounds to continuous Retro Funding, where projects are evaluated and rewarded on an ongoing basis. Current focus areas include developer tooling, on-chain builders, and contributions across the Superchain ecosystem.

Best for: Developers who build impactful public goods for the Optimism and broader Ethereum ecosystem. You do not need approval before building. Ship something useful, demonstrate impact, and apply for retroactive funding. The barrier to entry is lower than it appears: even small but widely-used tools have received significant RetroPGF allocations.

Apify launched the $1M Challenge in November 2025, running through January 31, 2026. The challenge invited developers worldwide to build automation tools (called "Actors") for the Apify Store. 704 developers participated, publishing 3,329 Actors, of which 1,086 qualified for prizes. The tools built include web scrapers, MCP servers, automation workflows, and AI agent tools, all now live on the Apify Store.

The prize structure rewarded both quality and user adoption. Grand prizes awarded $30,000 (first), $20,000 (second), and $10,000 (third) by jury selection. Weekly spotlight prizes of $2,000 were given for exceptional code quality, innovative concepts, or outstanding UX. Actor usage rewards paid $2 per monthly active user, from a minimum of $100 (50 users) to a maximum of $2,000 (1,000 users) per Actor, up to $10,000 across five Actors.

Bountycaster is a crypto-native bounty platform built on Farcaster, the decentralized social protocol. Co-founded by Linda Xie (early Coinbase PM, former Scalar Capital co-founder) and Daniel Pyrathon (ex-Phantom, ex-0x), Bountycaster bridges the crypto social scene and the gig economy. Users post bounties by tagging @bountybot on any Farcaster client (like Warpcast), and the AI-powered bot automatically lists the bounty.

Bountycaster takes no fees from either bounty posters or completers; transactions are peer-to-peer. Supported payment tokens include USDC, ETH, DEGEN, OP, and various creator tokens on Base. Bounties range from small design tasks ($20-$100) to substantial development work ($1,000-$5,000). Because bounties are tied to Farcaster identities, your reputation compounds over time through aggregated cross-platform data.

All bounties are tracked as GitHub Issues in the marketplace service template repository. Each issue includes the service specification, expected inputs/outputs, acceptance criteria, and bounty amount.

# Browse open bounties
open https://github.com/bolivian-peru/marketplace-service-template/issues

# Filter for open bounties with labels
# Look for issues labeled "bounty" and "open"

Comment on the GitHub Issue to claim the bounty. Include a brief description of your approach and estimated timeline. The Proxies.sx team will assign the issue to you and update the status.

# Example claim comment on GitHub Issue:
"Claiming this bounty. I plan to build the service using Python
with Playwright for browser automation, routing through Proxies.sx
mobile proxies. Estimated completion: 5 days."

Fork the marketplace-service-template repository and implement your service following the template structure. Your service should accept inputs via the defined API schema and return structured output. Route all web requests through Proxies.sx mobile proxy infrastructure.

# Fork and clone the template
git clone https://github.com/YOUR-USERNAME/marketplace-service-template.git
cd marketplace-service-template

# Install dependencies
npm install

# Configure proxy connection
export PROXY_HOST="your-port.proxies.sx"
export PROXY_PORT="your-port-number"
export PROXY_USER="your-username"
export PROXY_PASS="your-password"

# Implement your service in src/
# Follow the template structure for API endpoints

# Test locally
npm run dev
npm run test

Open a Pull Request against the main repository with your implementation. Link it to the GitHub Issue. The Proxies.sx team reviews the submission against the acceptance criteria: does it work, does it handle errors gracefully, does it use mobile proxies correctly, and does the output match the specification.

# Push your implementation
git add .
git commit -m "Implement [service-name] bounty service"
git push origin main

# Open a PR on GitHub linking to the bounty issue
# Include: demo output, test results, proxy usage logs

Once the PR is approved and merged, the bounty amount in $SX token is transferred to your wallet. Your service is deployed to the Proxies.sx marketplace, where it can generate ongoing revenue from users who pay per-request via the x402 protocol. The bounty is your initial payment; ongoing marketplace revenue is the long-term upside.