Senior Software Engineer - Payment Processing - Contract

Finalsite

5d•Remote

About The Position

Finalsite is hiring a Senior Software Engineer to help modernize its payment processing engine, the reconciliation and transaction-processing layer behind its payments business. The engine currently lacks end-to-end transaction tracking, relies largely on manual reconciliation, and has two parallel versions operating with separate processor integrations. Baseline automated reconciliation is a substantial, multi-quarter effort already underway. This high-visibility role will help close reconciliation gaps and build a scalable payments platform with automated reconciliation, fraud detection, and chargeback management. The position involves backend engineering across the engine’s two versions and processor integrations, collaboration with the storefront team, and contributions to a shared payments-unification layer spanning the payment processing engine, storefront, and events platform. The codebase is large, undocumented, and spread across multiple repositories without modern service boundaries. The posting describes the role as fully remote, but also states that employment is limited to permanent U.S. residents and requires current and continued U.S. residency; these location statements conflict with the listing’s “Anywhere in LatAm” location. Finalsite supports K–12 schools and districts with websites, communications, mobile apps, enrollment, and marketing services. The company describes its culture as collaborative and says it invests in employees through competitive benefits and professional development opportunities.

Requirements

At least 8 years of overall engineering experience, including strong backend engineering experience; experience with financial reconciliation, ledger, fraud, or transaction-processing systems is ideal.
Hands-on PCI compliance experience and familiarity with PCI-DSS requirements as they apply to transaction processing and reconciliation.
Bachelor’s degree in Computer Science, Engineering, or a related field, or equivalent practical experience.
Comfort working in a large, non-microservices codebase spanning many repositories without modern service boundaries.
Ability to trace and reason about data across disconnected systems.
Ability to make backend architecture decisions independently, including service boundaries, data modeling, and system-design trade-offs.
Experience with third-party payment processor integrations, including running two integration versions in parallel.
Strong backend engineering fundamentals with a .NET / SQL Server-based stack, or demonstrated ability to ramp quickly in one.
Working knowledge of relational database design and operations using SQL Server, including schema design, query-performance tuning, and locking behavior at production scale.
Familiarity with running and debugging a production service in a cloud environment; Azure is preferred.
Demonstrated expertise in at least one programming language, ideally .NET, Java, or Python.
Experience with at least one observability platform, such as Datadog, New Relic, Honeycomb, or comparable.
Deep experience with automated testing frameworks.
Proficiency with Claude Code, Codex, or comparable AI-assisted development tools.

Nice To Haves

Experience with .NET or Java specifically.
Deep experience with Azure.
Experience building reconciliation, ledger, fraud-detection, chargeback, or other payment-operations systems.
Prior work consolidating or migrating between two parallel versions of the same system.
Background in payments or fintech, particularly in high-volume environments.

Responsibilities

Design and build toward automated, end-to-end transaction lifecycle tracking, replacing the current manual reconciliation process.
Help build fraud detection, chargeback management, and other automated payment functions.
Work across the engine’s two parallel versions and processor integrations to resolve mismatches and reconciliation gaps.
Partner with the storefront team to expose data that closes reconciliation gaps.
Focus on quality, core-flow stability, and scalability as transaction volume grows.
Help plan and contribute to a shared payments-unification layer across the payment processing engine, storefront, and events platform.
Use AI-assisted development tools such as Claude Code, Codex, or comparable tools to navigate a large, undocumented, multi-repository codebase.