Staff Software Engineer (Fintech)

Benepass

3d•$200,000 - $240,000

About The Position

Benepass is building financial infrastructure that powers how companies fund, control, and deliver benefits globally. We are hiring a Senior Software Engineer to own and evolve the systems at the core of our platform: ledgering, transaction processing, decisioning, and money movement. These systems are responsible for tracking and moving real funds, enforcing complex rules, and maintaining a precise and auditable source of truth. This role is ideal for engineers who have built or operated systems in payments, card issuing, wallets, banking infrastructure, or global money movement platforms, and want to take end-to-end ownership of a growing fintech layer.

Requirements

Experience building or operating financial systems such as payments, card issuing, wallets, or banking infrastructure
Deep understanding of fintech and payments ecosystems, including: Card network fundamentals (e.g., ISO 8583 messaging, authorization/clearing/settlement flows), Merchant acquiring and payment processor flows, How issuers, sponsor banks, and processor integrations work in practice
Familiarity with real-world transaction lifecycles across the stack (network → processor → ledger)
Experience designing or working on a ledger system, including: Double-entry accounting concepts, Transaction lifecycles, Balance correctness and reconciliation
Experience building decisioning systems in production (e.g., transaction authorization, rules engines), ideally in real-time or latency-sensitive contexts
Experience working on systems that handle real money at scale (thousands of transactions per day or more)
Experience with global money movement, including: Multi-currency systems, Currency conversion or FX considerations
Strong understanding of: Data consistency and correctness, Idempotency and safe retries, Failure modes in distributed systems
Experience integrating with external financial APIs, including handling partial failures, timeouts, and eventual consistency
Proficiency in Python and relational databases (PostgreSQL preferred)
You think in systems, not endpoints
You don’t just build APIs — you design systems that model real-world financial behavior. You understand how money moves through a system, how state changes over time, and how to ensure that state remains correct under failure.
You prioritize: Accurate balances over eventual fixes, Clear invariants over implicit assumptions, Systems that are easy to reason about under stress
You’ve seen what goes wrong in financial systems — and you design to prevent it.
You’ve worked on systems with: Multiple sources of truth (and resolved them), Asynchronous workflows and external dependencies, Subtle edge cases (duplicates, race conditions, reconciliation gaps)
And you know how to simplify where it matters.
You are comfortable owning systems where: Failures are visible and impactful, Debugging requires tracing through distributed systems, Long-term maintainability matters as much as short-term delivery
You write clear design docs and communicate trade-offs effectively
You mentor other engineers in system design and domain understanding
You push for better patterns, better abstractions, and better systems

Nice To Haves

Cross-border transactions (nice to have but strongly preferred)

Responsibilities

Design and operate systems responsible for: Ledgering (double-entry systems, balances, transaction history, reconciliation), Transaction processing pipelines (authorization, capture, settlement flows), Real-time decisioning (spend controls, eligibility, rules engines), Money movement, including support for multi-currency and global transactions
Build systems that are correct by design: Define and always maintain invariants to ensure correctness under all operational conditions, Idempotent, Strongly consistent where required, Fully auditable
Own the lifecycle of financial transactions end-to-end, including: State transitions, Failure handling and retries, Reconciliation and reporting
Integrate with external financial partners (processors, banks, networks) and handle unreliable and asynchronous dependencies
Lead architectural decisions and write technical approach documents that clarify trade-offs and long-term implications
Improve system resilience, observability, and operational tooling as volume and complexity grow
Mentor other engineers and help define best practices for building financial systems