Java / Wallet Blockchain Infrastructure Engineer (full-time)

About Artkai

Artkai is an international digital product development house and service company. For over 10 years, we have been building complex solutions for partners across the US and Europe, focusing on high-quality engineering and integrated service delivery.

Industry: Blockchain / Fintech / Custodial Services

Engagement Type: Outstaffing contract via Artkai

Duration: Long-term engagement

Workload: Full-time

Location: Remote (European time zone)

Role Overview

On behalf of our partner, we are looking for a Wallet Infrastructure Engineer to build an internal wallet technology platform for custodial operations. The primary goal is to replace a fragmented setup of multiple vendor-specific tools with a unified, client-owned stack. The platform will consolidate policy engines, wallet registries, and governance frameworks into a single system.

Key Responsibilities

• Infrastructure Consolidation: Replace multiple vendor-specific tools with a unified, client-owned technology stack.
• Wallet Management: Oversee wallet registries and comprehensive wallet management workflows.
• Transaction Engineering: Handle end-to-end transaction construction and execution across multiple protocols.
• Signing Coordination: Develop and manage secure signing coordination processes.
• Policy & Governance: Implement policy engines and governance frameworks to ensure secure custodial operations.

Required Skills & Qualifications

• Backend Stack: Strong proficiency in Java development.
• Blockchain Protocols: Direct experience with BTC, Solana, ETH, and TRON.
• Wallet Expertise: Practical knowledge of wallet infrastructure and multichain custodial operations.
• System Integration: Ability to merge policy engines, wallet registries, and governance into a single platform.
• Language: Professional English proficiency (written and verbal) for technical collaboration (B2+).

What We Offer

• Direct Impact: Full ownership over building a core custodial platform from scratch.
• Long-term Growth: Stable engagement within a high-stakes blockchain infrastructure project.
• Flexibility: Full-time remote work arrangement within the European time zone.