Senior Software Engineer, Technical Leadership / Platform

Role OverviewThis is a Senior Software Engineer role with a Technical Leadership / Platform specialization, focused on system design, reliability, and long-term platform evolution. You will help the team understand how our systems should behave under load, during failures, and as they scale, ensuring the platform foundation remains healthy over time. The role involves a significant architectural focus (30-50%) while remaining fully hands-on: you take ownership of the most complex or high-risk backend work, and act as the technical representative for API/SDK integrations with third-party vendors and clients, during and after the integration.Key Responsibilities Design and evolve core platform services, focusing on reliability, data integrity, and clear service boundaries aligned with business requirements Identify architectural risks, scalability limits, and weak points before they become production issues; recognize when existing tools (queues, storage, frameworks) reach their limits and propose pragmatic, incremental improvement or migration paths Own the technical relationship with partners as the primary technical point of contact: lead solution reviews, troubleshooting, and roadmap alignment; document technical decisions and integration details; ensure partners understand expectations, timelines, and constraints Design and improve reliability mechanisms: retries and backoff, timeouts and idempotency, handling of partial failures, degraded and fallback modes Drive improvements in observability (metrics, logs, tracing, operational visibility) and participate in production incident analysis Contribute during the Discovery stage of projects: build PoCs, validate ideas, analyze third-party vendor APIs and proposed integration flows Implement the most complex and high-risk backend components using TypeScript and Node.js, owning correctness under partial failure scenarios Raise the overall technical maturity of the team, including senior engineers: thoughtful code reviews, decomposition of large or ambiguous problems, knowledge sharing through pairing and documentation Required Qualifications 6+ years of professional backend development experience Deep hands-on experience building and operating crypto infrastructure: custody, wallets, exchange, payment, or settlement systems. You have designed and run production systems that move real funds. Integrating a crypto API into an existing product, or building UI on top of one, does not meet this bar Strong backend expertise in TypeScript and Node.js Deep experience in distributed system design: microservices architecture, service boundaries and data models, REST APIs and API contracts, queues and asynchronous communication Hands-on production experience: incident response, debugging, API failures, data issues Experience owning services end-to-end, from design to production support Excellent knowledge of SQL (PostgreSQL) and understanding of other storage types Strong reliability mindset and experience with failure scenarios; experience improving observability and investigating production incidents Proficient daily use of AI coding tools (e.g. Claude Code, Copilot), with the ability to review AI-generated code quickly and critically Ability to mentor engineers, including senior-level, and to evaluate trade-offs and propose practical solutions High agency: you treat problems in your scope as yours by default, act before being asked, and escalate with a proposed plan when a decision is above your level Excellent communication skills, with the ability to bridge technical and business conversations; strong written and verbal English Preferred Experience Experience leading architecture work across timezones in a distributed team Experience in regulated financial environments (licensing, audits, compliance-driven engineering requirements) Experience with queues and event-driven systems (Kafka, RabbitMQ, SQS, etc.) Redis or other in-memory data stores Familiarity with Docker, Kubernetes, and AWS (user-level understanding) Experience shaping team practices around AI-assisted development Reporting StructureReports to the Engineering Manager. This role does not include direct people management, only technical influence.Why This Role Own the technical foundation of a crypto payment platform being built now: architecture decisions you make will define the platform for years Full technical ownership of the highest-risk, highest-impact work in the company, with direct influence on how the whole engineering organization builds AI-first engineering culture where your leverage multiplies through the team LocationRemote. USA, Argentina, or Brazil. The role works US business hours (Eastern Time). A minimum of 4 hours of daily overlap with Central European working hours is a requirement.Compensation and BenefitsAs an independent contractor, you'll enjoy the flexibility to determine how and when you deliver your work, while partnering closely with our team to meet agreed milestones and b