Hire senior blockchain developers for smart contracts and Web3
Senior blockchain engineers who write and test smart contracts, build indexers and wallet flows, and integrate chains with your systems, on US hours.
By the Ryz Labs team · Updated October 2026
Hiring blockchain developers through Ryz gets you senior engineers who write smart contracts as if every line could cost money, because it can. They are in the top 1% of the engineers we interview, they join your team and repos, and they work on US business hours.
What our blockchain developers work on
Blockchain work combines on-chain code that is hard to change with off-chain systems that must stay in sync with it. Our engineers work with Solidity and Vyper on Ethereum and EVM chains, Rust on Solana, Foundry and Hardhat, OpenZeppelin libraries, ethers.js and viem, The Graph, and node providers such as Alchemy or Infura. Typical projects:
- Smart contracts for tokens, payments, escrow, staking and tokenized assets, built on audited libraries.
- Layer 2 deployments on networks such as Arbitrum, Optimism and Base, and bridging between chains.
- Backends that index on-chain events, reconcile balances and feed internal systems and dashboards.
- Wallet and custody integrations, including account abstraction, multisig flows and transaction signing services.
- Stablecoin payment flows and settlement systems for fintech and financial services teams.
- Audit preparation and remediation: test coverage, fuzzing, invariant tests and fixes for audit findings.
Skills we vet for
- Solidity and the EVM. Storage layout, gas costs, calldata versus memory, events, and how the EVM executes calls.
- Smart contract security. Reentrancy, access control, oracle manipulation, front-running, integer and rounding issues, and signature replay.
- Testing. Foundry unit, fuzz and invariant tests, mainnet forking, and static analysis with Slither.
- Upgradeability. Proxy patterns such as UUPS and transparent proxies, storage collisions, and when not to make a contract upgradeable.
- Solana and Rust. The account model, Anchor, program-derived addresses and compute limits, for teams building on Solana.
- Off-chain infrastructure. Event indexing, handling chain reorganizations, nonce management and reliable transaction submission.
- Key management. Hardware security modules, multisig and MPC custody, and keeping private keys out of application code.
- Standards. ERC-20, ERC-721, ERC-1155, ERC-4626 vaults and ERC-4337 account abstraction.
How we vet blockchain developers
Recruiters look for blockchain engineers with deployed contracts and production off-chain systems, and they review public code where it exists. ARC, our in-house system, ranks the pipeline. Candidates complete a structured NTRVSTA AI interview on contract security, the EVM or Solana runtime, and system design. Recruiters review each candidate before and after the interview and send you a curated shortlist. AI scores are advisory. Humans decide who moves forward.
Sample interview topics
- Walk through a reentrancy attack on a withdraw function, then explain why checks-effects-interactions alone may not cover cross-function or read-only reentrancy.
- A lending contract reads a token price from a single DEX pool. How could an attacker exploit that in one transaction, and what would you use instead?
- You need to add a field to an upgradeable contract's storage. What can go wrong with the layout, and how do you test the upgrade?
- Your indexer shows a deposit that later disappears from the chain. How do you design the backend to handle reorganizations and finality?
- Write invariants for a vault contract. Which properties should always hold, and how would you test them with Foundry?
Ways to hire blockchain developers
| Option | Best for | Trade-offs |
|---|
| Freelance marketplace | A test token or a proof of concept | Smart contract mistakes are permanent and public. Verifying security skills is up to you. |
| Staffing or recruiting agency | General engineering hiring | Few agencies can test contract security. Web3 titles vary widely in meaning. |
| In-house recruiting | Long-term protocol or platform owners | Experienced blockchain engineers are scarce and often prefer protocol work. |
| Ryz Labs staff augmentation | Adding senior blockchain engineers to an existing product or platform team | You own architecture and security review. Best when your audit and release process is set. |
| Ryz Labs dedicated team | A defined on-chain product with its backend and integrations, built by one team | A tech lead plus contract and backend engineers, scoped together with a plan. |
Ryz is not the right fit if you want hourly freelance help booked without a conversation, or if you need engineers in European or Asian time zones. We also do not replace an independent security audit; our engineers prepare code for one and fix what it finds.
Why hire blockchain developers from Latin America
Latin America has an active blockchain community, with developer meetups, hackathons and protocol teams in cities like Buenos Aires, São Paulo and Mexico City. Interest in stablecoins and digital payments in the region has given many engineers practical experience with real users and real money, not only test networks.
Contract deployments, audits and incident response all need fast coordination. Working on US business hours, our blockchain developers can review audit findings with your security lead, agree on fixes and redeploy to a testnet the same day. They work in English and follow your review and release process.
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FAQ
Which chains do your blockchain developers work with?
Most work on Ethereum and EVM-compatible chains and Layer 2 networks. Some specialize in Solana with Rust. Tell us your chain and we match on it.
Can they help enterprise teams that are new to blockchain?
Yes. Our engineers often work with financial services and payments teams adding stablecoin or tokenization features to existing systems, and they explain the trade-offs in plain terms.
How much does it cost to hire blockchain developers?
$7,000 to $15,000 per engineer per month, scoped per team. You get a plan, a price and the names of the people who would do the work before you sign.
What hours do they work, and how do they fit into our team?
Our engineers work on your team, reporting to your own leads. They work on US business hours. Talk to us to scope the team you need.
Questions we didn't answer? Email info@ryzlabs.com.