What a blockchain developer does
A blockchain developer builds the software that runs on or connects to a distributed ledger. Depending on your product, that could mean writing smart contracts in Solidity or Rust, building services that read and index on-chain data, integrating wallets and custody providers, or running nodes and infrastructure. Because deployed contracts are hard to change and often control real funds, the work demands careful design, thorough testing and an honest view of risk.
A strong hire lets you ship features with confidence and reduces the chance of an exploit, a failed upgrade or expensive transaction fees for your users. A weak one can leave vulnerabilities that only surface after launch. Finch learns which networks, languages and frameworks you use, whether you build on public chains or private enterprise ledgers, and how your team handles audits, then screens candidates against those specifics.
Typical responsibilities
- Design and write smart contracts, upgrade patterns and supporting libraries
- Build back-end services that index, monitor and react to on-chain events
- Integrate wallets, custody providers, oracles and bridges into your applications
- Write unit, fuzz and integration tests, and deploy to test networks before main network releases
- Optimize contract code for gas costs without weakening security
- Prepare code and documentation for external audits and fix the findings
Qualifications and credentials
- A degree or diploma in computer science or software engineering is common, though many employers hire on demonstrated work
- Production experience with Solidity on EVM networks, or with Rust, Go or Move on other chains
- Working knowledge of frameworks such as Foundry or Hardhat and libraries such as ethers.js
- Understanding of common vulnerability classes, including reentrancy, access control flaws and oracle manipulation
- Experience with enterprise platforms such as Hyperledger Fabric is an asset for private-ledger projects
Who hires a blockchain developer
- Crypto trading platforms and custody providers
- DeFi protocols and Web3 start-ups
- Banks, payment companies and fintech firms exploring tokenization
- Blockchain consultancies and development studios
- Gaming and digital collectibles companies
Where we recruit blockchain developer candidates
We fill blockchain developer roles for employers across Toronto and the GTA, including North York, Scarborough, Etobicoke, Vaughan, Markham, Richmond Hill, Mississauga, Brampton, Oakville, Burlington, Oshawa and Pickering, and for employers across Canada. GTA employers can meet us at our North York office by appointment.
What Finch checks before you meet a candidate
- Contracts or repositories the candidate wrote, what they do and whether they are live on a main network
- How they test, review and deploy code, and which tools they rely on
- How they responded to audit findings or incidents on past projects
- Depth in the specific chain, language and framework you use
- Eligibility to work in Canada and availability for your remote, hybrid or office setup
Interview questions to ask
- Walk me through a contract you deployed to a main network. What did the audit find, and what did you change?
- How do you decide whether a contract should be upgradeable, and what risks does an upgrade pattern add?
- Describe how you would test a function that moves user funds before it goes live.