Senior Software Engineer — Backend

Cari Network is building a blockchain-based payment system for real-time movement of digital money across traditional finance and digital asset ecosystems. The Senior Software Engineer — Backend will own transaction-processing infrastructure for signing and settlement flows, including ordering, concurrency control, data models, APIs, reliability, incident response, and cross-team platform integration.

Responsibilities:

• Own our transaction processing platform infrastructure for signing and settlement flows—service design, correctness guarantees, and operational health
• Own the transaction-ordering and concurrency-control logic that keeps our transaction processing platform correct and consistent at scale
• Design data models, API contracts, and retry/backoff logic for the services you own; write RFCs that Banking and Blockchain engineers rely on when integrating against your services
• Define what "production-ready" means for platform services you own: SLOs, alerting thresholds, and runbooks
• Lead incident response and root-cause analysis for the services in your domain, and drive postmortems that prevent recurrence
• Reason about consistency models, failure modes, and capacity for the systems you own, and flag architectural risk before it becomes an incident
• Coordinate directly with Banking and Blockchain engineers who depend on your services, translating their requirements into platform capabilities

Requirements:

• 5–7 years of backend software engineering experience, ideally including systems with strict correctness or ordering guarantees (financial transactions, ledgers, distributed queues)
• Strong proficiency in TypeScript
• Experience with durable workflow or orchestration systems (e.g. Temporal or similar)—either operating one in production or designing services on top of one
• Solid understanding of concurrency control patterns: partitioned/keyed execution, idempotency, at-least-once delivery, and reconciliation
• Production experience with PostgreSQL and Kafka or equivalent message infrastructure
• Comfortable owning a service independently, including the judgment calls on reliability and design that come with it
• Strong written communication—you'll be writing RFCs that people outside your immediate team act on
• experience with Effect (effect.ts) or a comparable functional effect system strongly preferred
• Prior work in fintech, payments, or another regulated financial infrastructure environment
• Experience with blockchain or custody-adjacent systems (transaction signing, nonce management)
• Familiarity with Terraform or infrastructure-as-code for provisioning the services you own
• Experience mentoring engineers or driving cross-team technical alignment