How to Hire a Blockchain Developer (From Someone Who Is One)

Most blockchain job posts ask for the wrong things.

I've been hired to do this work, and I've sat on the other side reviewing portfolios and interviewing people. The same mistakes come up every time. So here is what I'd tell a founder or hiring manager before they start looking.

Your Job Post Is Probably Wrong

I see the same post over and over. "Looking for Solidity developer with 5+ years experience. Must know DeFi, NFTs, Layer 2, cross-chain bridges, zero-knowledge proofs, and MEV strategies."

That's not a job description. That's a wishlist for a person who doesn't exist. And if they do exist, they cost $300/hour and they're booked for the next year.

Here is the part most companies miss. You probably don't need a protocol-level Solidity engineer. (Solidity is the language smart contracts are written in.) You need someone who can connect blockchain to your app. Those are two different jobs.

Integration Developer vs. Protocol Developer

This split matters more than anything else in your hiring.

Protocol developers build the blockchain plumbing itself. They write smart contracts from scratch, design token economics, and audit security at the bytecode level. They think about gas, formal verification, and consensus.

Integration developers connect that plumbing to apps. They build the frontend that talks to smart contracts. They set up wallet connections, handle transactions, read on-chain data, and build the part users actually touch.

Most companies need the second kind. You already have a product. You want to add blockchain features. You need someone who knows both Web2 and Web3 tooling.

When I built the frontend for Ajna Labs' DeFi lending protocol, the smart contracts already existed. My job was the React and TypeScript app that let users move on-chain liquidity. That's integration work. Building the SDK that cut integration time for other developers, that's integration work too.

Post a job for a deep Solidity expert when you really need someone to wire your React app to a wallet, and one of two things happens. You scare off the right people. Or you hire someone overqualified who's bored in a month.

What to Actually Look For

Skip the buzzword bingo. Here is what matters.

1. Frontend Framework Expertise (React/TypeScript)

This may surprise you. The most important skill for most of these roles is plain frontend engineering. The blockchain parts are libraries and APIs. The hard part is building a reliable, fast app around them.

If someone can't build a solid React app, they can't build a solid Web3 app. Simple as that.

2. Web3 Library Fluency

They should know ethers.js or viem, wagmi or web3-react, and how to talk to smart contracts through ABIs. (An ABI is the list that tells your code what functions a contract has.) Ask them the difference between a call and a transaction. Ask how they handle chain switching. Ask what happens when a transaction fails halfway through.

If they go blank, they haven't shipped anything real.

3. Wallet and Transaction Flow Understanding

A "connect wallet" button is easy. The job is handling the 47 things that go wrong after someone connects. Wrong network, not enough gas, rejected transactions, pending states, chain reorgs, RPC failures.

Ask how they handle error states in wallet flows. The answer tells you how much production work they've done.

4. Smart Contract Literacy (Not Necessarily Authorship)

For integration roles, your developer needs to read Solidity, not write it from scratch. They should look at a contract's ABI, know what each function does, and call it correctly from the frontend.

Writing complex contracts is its own skill. If you need that, hire for it on purpose. Don't expect a frontend-focused developer to also audit contracts.

5. Problem-Solving Over Tool Knowledge

Blockchain tooling moves fast. The person who memorized the web3.js API in 2021 is probably on wagmi and viem now. What matters is whether they can find the right approach when the docs are thin and the Stack Overflow answers are two years old.

Ask about a time something broke in production. How did they debug an on-chain issue? How did they handle a contract that wasn't behaving?

Red Flags in Interviews

Watch for these.

"I've built 20 NFT projects." If the whole portfolio is NFT minting sites from the 2021 to 2022 hype, the depth may not be there. A lot of those were copy-paste jobs with little engineering.

They can't explain gas. If a blockchain developer can't tell you what gas is, how it's estimated, and why transactions fail over it, they haven't built anything that handles real money.

No production experience. Testnet is not mainnet. Testnet has no real money, no real users making mistakes, no MEV bots front-running you. Ask specifically about mainnet deployments and production debugging.

They oversell decentralization. Good developers know most apps are partly centralized, and that's fine. If someone insists everything must be on-chain and trustless, they'll over-engineer your project and blow your timeline.

Vague portfolio descriptions. "Contributed to a DeFi protocol" could mean they built the whole frontend or fixed a CSS bug. Ask for specifics. What did they build? What did they decide? What would they do differently?

Questions to Ask When Evaluating a Portfolio

Don't just look at screenshots. Ask these.

"Walk me through the architecture of this project." You want to hear the stack choices, the on-chain vs. off-chain split, and why they made those calls.
"What was the hardest bug you hit?" Real projects produce memorable bugs. If they can't name one, they probably didn't build much.
"How did you handle wallet disconnections and network switches?" A boring detail, but it separates hobby projects from production apps.
"What would you change if you rebuilt it today?" Honesty about past decisions is a strong signal. If everything was perfect, they're not being straight with you.
"How many users or how much TVL did this handle?" Scale matters. Building for 100 users is not the same as building for 5 million. I've done both. Shiba Inu served over 5M users with 3K peak concurrent.

What to Expect on Rates

Let's talk money, because this is where founders get sticker shock.

Experienced blockchain developers are expensive. No way around it. The talent pool is small, bugs can lose real money, and the tooling takes specialized knowledge.

Here's a rough market read for 2026:

Junior blockchain developer (0-2 years): $40-70/hour
Mid-level integration developer (2-5 years): $70-120/hour
Senior integration developer (5+ years): $100-180/hour
Protocol/Solidity specialist: $150-300+/hour
Auditors: $200-500+/hour

I charge €75/hour for senior integration work. That sits at the practical end of the senior range. High enough that the work is solid, low enough that you're not paying for overhead.

If someone quotes you $30/hour, that's not a deal. That's someone who will cost you ten times that in debugging, security holes, and rewrites.

If a solo developer (not a firm) quotes $400/hour, ask what justifies it. Sometimes it's fair. Often it isn't.

The Hiring Checklist

Before you sign anyone, check these boxes.

You've decided whether you need an integration developer or a protocol developer
Your job description lists specific deliverables, not buzzword requirements
You've seen their code, not just portfolio descriptions
They can explain your project's blockchain architecture back to you in plain language
They have mainnet experience, not just testnet projects
Their rate fits the market for their experience level
They've asked YOU smart questions about your project constraints

That last one matters. A good developer will push back on bad ideas in the interview. If they agree with everything and promise they can build anything, they're selling you, not partnering with you.

So, before you write that job post: do you need someone to build the blockchain, or someone to connect it to your product?

Looking for a Blockchain Developer?

I focus on practical integration. Connecting blockchain to real products, without over-engineering or burning the budget.

If you're hiring and want to talk through what you actually need (and what you don't), let's have a conversation. Thirty minutes, no cost, no sales pitch. Just an honest look at your project.