Senior Blockchain Engineer

Quick Facts

• Role: Senior Blockchain Engineer (client-facing)

Description

You’ll work directly with a client team throughout the project, delivering secure blockchain-based money movement and wallet automation. The role focuses on building solutions on top of MPC/custodial wallet platforms, defining transaction policies and pre-execution checks, and ensuring strong security and auditability. DeFi/stablecoin knowledge is needed for confident integrations (deep smart-contract expertise is not required).

Responsibilities

• Scope a pilot process (including manual steps initially) and design a path toward automation

• Build lender/borrower accounts, collections wallets, transfers, and sweeps on an MPC custody platform

• Define transaction policies and pre-execution checks, including controls on permitted destinations

• Integrate outputs from external or internal calculation agents while keeping smart contracts out of the primary money-movement layer

• Design and implement automated wallet operations (deposit flows, sweeps, transfers) with security and auditability focus

• Collaborate with client product and business stakeholders to deliver solutions that meet real needs

• Take shared ownership from design through deployment and ongoing support

Requirements

• Hands-on experience building secure money movement solutions on MPC or custodial infrastructure (e.g., Fireblocks, Fordefi) primarily via API

• Experience with signing policies, transaction authorization, and wallet controls

• Experience with transaction automation and exchange-style flows (deposit and sweep flows)

• Knowledge of DeFi sufficient to design integrations confidently (deep smart contract expertise not required)

• Experience building production financial infrastructure dependent on critical business processes

• Strong software engineering fundamentals: clean, testable code with a focus on maintainability and security

• Ability to navigate trade-offs among security, delivery speed, automation, and cost; communicate clearly to technical and non-technical stakeholders

• English proficiency at C1 level or above

• Polish proficiency at B2 level or above

Benefits

• Training and wellbeing budget

• Work from home or office (up to 100% remote)

• LuxMed healthcare package

• Multisport card

• Long-term, stable collaboration with no dress code

• Team events and retreats