Senior Blockchain Backend Engineer – Remote EU

Appsierra Group; Brussel; Sur place; EUR 120 000 - 180 000; Plein temps

Résumé du poste

Appsierra Group is seeking an experienced blockchain engineer to lead backend integration with smart contracts, wallets and dApps across the EU region. The role requires deep hands-on expertise in Ethereum, Hyperledger Besu, Solidity and secure DevSecOps practices, with a track record of building scalable, compliant solutions.

You will design, develop and oversee tests, audits and deployments, mentor teams of developers, and collaborate with product owners and scrum masters.

Qualifications

• Bachelor's degree in IT, Engineering, Mathematics, Business Administration or Innovation.
• 15+ years of software development experience.
• 15+ years of software engineering principles and SDLC.
• Backend development with Java/JavaScript/TypeScript/Node.js (10+ years).
• 10+ years building blockchain smart contracts on EVM networks.
• 10+ years blockchain security and audit prep.
• 5+ years Ethereum smart contract development.
• 5+ years Solidity, EVM, proxy patterns, gas optimisation, RBAC.
• 5+ years Hyperledger Besu network engineering.
• 5+ years Besu validator networks.
• 5+ years blockchain identity and tokenisation.
• 7+ years blockchain standards incl ERCs, EIP-712, EIP-1559, DIDs.
• 5+ years blockchain security, DevSecOps tooling.
• 5+ years Foundry, Hardhat, OpenZeppelin, Slither, Mythril, fuzz testing.
• 5+ years ethers.js, VIEM, Gnosis Safe, hardware wallets, EIP-712 signing.
• 5+ years GitLab CI/CD.
• 5+ years Puppet.
• APIs integration with smart contracts, wallets and dApps.
• Secure backend development: auth, authorization, input validation, logging.
• Unit/integration testing in CI/CD.
• Write clean, functional backend code and docs.
• Troubleshooting, performance and scalability.
• Experience managing teams of developers.
• English: min B2, strong communication.
• Certified Scrum Master.
• Certified Product Owner.

Connaissances

Blockchain development

Ethereum

Hyperledger Besu

Solidity

EVM

Smart contracts testing

Back-end development

SDLC

DevSecOps

API design

GitLab CI/CD

Security auditing

Team leadership

Scrum Master

Product Owner

English

Foundry

Hardhat

OpenZeppelin

Slither

Mythril

ETHERS.js

VIEM

Gnosis Safe

Formation

Bachelor's degree in IT/Engineering

Outils

Foundry

Hardhat

OpenZeppelin

Slither

Mythril

SWC Registry

OWASP

ethers.js

VIEM

Gnosis Safe

Description du poste

Appsierra Group is seeking an experienced blockchain engineer to lead backend integration with smart contracts, wallets and dApps across the EU region. The role requires deep hands-on expertise in Ethereum, Hyperledger Besu, Solidity and secure DevSecOps practices, with a track record of building scalable, compliant solutions.

You will design, develop and oversee tests, audits and deployments, mentor teams of developers, and collaborate with product owners and scrum masters.