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Blockchain Engineer
Kaiko
Software Engineering
Paris, France
Posted on Jun 12, 2025
Founded in 2014, Kaiko is a global fintech company with offices in New York City, London, Paris, and Singapore. As a rapidly growing leader in the crypto market data and index industry, we serve financial institutions and enterprises engaged in digital assets.
What We Do
Kaiko provides financial data products and solutions, across four main business units:
Market Data: Level 1 and Level 2 data for both CeFi (Centralized Finance) and DeFi (Decentralized Finance) ecosystems, covering spot markets, derivatives, and lending protocols.
Analytics: Proprietary quantitative models and data solutions designed for pricing digital assets and assessing market risk.
Monitoring Solutions: Advanced market and blockchain monitoring tools for surveillance, compliance, and market exploration.
Indices: A diverse suite of mono-asset benchmarks and cross-asset indices, along with custom index creation and calculation agent services.
Kaiko’s products are available worldwide on all networks and infrastructures: public APIs, private & on-premises networks; private & hybrid cloud set-ups; blockchain native (Kaiko on-chain delivery).
Additionally, Kaiko’s Research publications are read by thousands of industry professionals and cited in the world’s leading media organizations. We provide original insights and in-depth analysis on crypto markets using Kaiko’s data and products.
Who We Are
We’re a team of +80 (and growing) passionate individuals with a deep interest in building data solutions and supporting the growth of the digital finance economy. We’re proud of Kaiko’s talented team and are committed to our international representation and diversity. Our people and their values are the foundation of our continued success.
As a Senior Blockchain Engineer, you’ll play a critical role in shaping the architecture and implementation of our core blockchain systems. You’ll work at the intersection of smart contract development, protocol design, and system security, helping bring new decentralized products and infrastructure to life. Whether designing efficient on-chain logic, scaling our platform across L2s, or integrating with external protocols, you’ll own projects end-to-end and collaborate closely with product, design, and fellow engineers. This is a high-impact role for someone who thrives in a fast-paced environment and is excited to help build the future of blockchain/web3.
Missions & Responsibilities
- Design and implement data extraction pipelines from multiple blockchains (EVM-compatible and non-EVM).
- Ability to design, implement, and deploy smart contracts on Ethereum or other relevant blockchains.
- Deep understanding of Blockchain technology (Solidity, Vyper), Oracles, and Decentralized Finance (Curve, Balancer, AMMs, Yearn, Aave, Synthetix ... etc): ideally, you have used and integrated these protocols before
- You can abstract the complexity of low-level smart contract interactions through scripting and REST APIs
- Participate in the engineering on-call rotation to ensure platform stability, monitor for production issues, and respond to critical incidents.
- Write thorough documentation and conduct peer code reviews.
- Work closely with product team to develop technical solutions from concept to production.
- Stay current with the latest developments in blockchain protocols, tooling, and standards (e.g., EIPs, ERCs, L2 scaling, etc.).
About you
- 5+ years of professional software engineering experience, with at least 3 years focused on blockchain development.
- Comfortable working with one or more smart contract languages (Solidity, DAML, Move, etc.).
- Deep understanding of blockchain fundamentals: consensus mechanisms, EVM, transaction lifecycle, gas optimization, etc.
- Experience with web3 libraries and tools (e.g., Hardhat, Foundry, ethers.js, web3.js).
- Strong experience in backend development with Go and good understanding of microservices architecture.
- Experience deploying and managing applications in kubernetes
- Comfortable working in a fast-paced startup environment with an ownership mentality.
Preferred Qualifications
- Contributions to open-source blockchain projects.
- Experience working with zero-knowledge proofs, bridges, or rollups.
- Familiarity with wallet development, custodial/non-custodial key management.
- Previous experience integrating blockchain with traditional finance systems (TradFi).
Location: Global
Type of contract: Full-time
What we offer
● Competitive paid holidays
● The hardware of your choice
● Great health insurance
● Contribution to your monthly gym subscription
● Remote-friendly
● Multiple team events (team retreat, casual drinks, etc.)
● An entrepreneurial environment with a lot of autonomy and responsibilities
● Others
Talent Acquisition Process
● Call with the People team (20 min)
● Interview with the Hiring Manager (45 min)
● Technical test / Business Case (1h )
● Cross team interviews with 2-3 team members (30 min)
● Interview with CPTO (45m to 1h)
● Offer, reference check
Diversity & Inclusion
At Kaiko, we believe in the diversity of thought because we appreciate that this makes us stronger. Therefore, we encourage applications from everyone who can offer their unique experience to our collective achievements.