Blockchain Integration Engineer / Backend Engineer (Go + PHP)

Company: Sheepy Location: Moscow Salary: from 4000 USD Experience: More than 6 years Key skills: PHP, Golang

Blockchain Integration Engineer / Backend Engineer (Go + PHP)

We are looking for an engineer to integrate and maintain existing L1 / L2 blockchains into our existing crypto payment management platform (production). This role does not involve developing blockchains from scratch.

The platform consists of several microservices:

• the core platform for scanning blocks, processing transactions, and withdrawals is written in PHP (Laravel)
• a microservice written in Go using the trustwallet library - wallet-core has been created for generating addresses, validation, and creating signed offline transactions

The main focus is on connecting, developing, and operating blockchain integrations. In this role, the engineer is responsible for integrating specific blockchain networks – from connection to stable production operation.

The platform is actively in use: several blockchain networks, real B2B merchants, a constant stream of transactions.

What you will do:

• Integrate new L1 / L2 blockchains into the existing payment infrastructure and maintain these integrations in production

• Implement and support the full cycle of blockchain network operations:

  • address generation and validation
  • monitoring of incoming transactions (inbound scanners)
  • confirmation and finality logic
  • handling of N-block reorgs and correct balance recalculation
  • calculation and unification of fees (gas / fee / priority fee)
  • creation and sending of outgoing transactions
  • working with stuck transactions, nonce management

• Connect and maintain company nodes and third-party providers (RPC, WebSocket, JSON-RPC), ensuring their stable operation

• Respond to hard forks / chain upgrades and protocol changes without service interruption

• Unify various blockchain networks under a single management interface

• Diagnose production incidents and participate in ensuring stable integration operation

• Implement monitoring of nodes and network status

• Document integrations and technical solutions

• Participate in designing architectural solutions and abstractions for connecting new blockchains

• Autonomous work: minimal meetings, high responsibility for results

What is important for this role:

• Proficient in Go (Golang) - the primary language for integrations

• Proficient in PHP (support and integration with existing code)

• Understanding of microservice architecture

• Experience with MySQL, Redis

• Practical experience with Blockchain / Crypto

• Experience integrating blockchains as payment rails

• Understanding of the differences:

  • account-based and UTXO models
  • probabilistic and deterministic finality

• Experience with at least one of the following:

  • EVM-compatible networks
  • Non-EVM networks (Bitcoin-like, Solana, Tron, etc.)

• Understanding of gas mechanics, mempool, confirmations, reorg / rollback scenarios

• Experience with raw transactions, signing, private keys

• Practical experience using Trustwallet wallet-core

Will be a plus:

• Experience integrating L2 solutions (Optimistic / ZK rollups)
• Understanding of compliance aspects (KYT, transaction tracing)
• Experience in fintech / payment systems
• Experience developing high-load systems with financial responsibility

Conditions and opportunities:

• Participation in an international fintech project focused on cryptocurrency payments and B2B solutions
• Fully remote work format
• Flexible processes and minimal meetings
• Work in a team of backend and blockchain engineers with high autonomy and responsibility for results
• Mentorship and support at the start, opportunities for professional growth
• Competitive compensation (discussed individually based on interview results)
• Transparent processes, clear task system, and regular feedback
• Tools: Agile, Redmine, Telegram, Discord.