Backend Engineer – Payments & Infrastructure

arcadia; San Francisco (CA); On-site; USD 140,000 - 210,000; Full time

Job summary

Arcadia seeks a Backend Engineer to own the reliability, scalability, and architecture of its core fintech infrastructure. You will build and scale payment systems, ledger integrity, and data pipelines in a fast-growing startup environment.

You’ll work with a small, highly technical team to own end-to-end projects from design to production, driving reliability, security, and compliance in high-volume financial transactions.

Qualifications

• Production-grade backend systems experience.
• Experience with distributed systems and microservices.
• Strong reliability, scalability, fault tolerance, and performance knowledge.
• Experience with financial infrastructure or transactional applications.
• Database design, data integrity, and transaction reconciliation expertise.
• Familiarity with asynchronous processing and queues.
• CI/CD pipelines, automated testing, monitoring, and cloud infrastructure experience.
• Ability to own complex technical projects end-to-end, from architecture to production deployment.
• Proactive, ownership-driven approach to engineering.

Responsibilities

• Own Core Backend Infrastructure: Design, build, and maintain reliable, scalable backend services powering payments and transactions.
• Build & Scale Payment Systems: Develop infrastructure supporting payment processing, card issuing, and financial integrations.
• Ensure Ledger Integrity & Reconciliation: Build systems for automated reconciliation and transaction validation across services.
• Scale Distributed Systems: Architect services to handle growth in users, transactions, and complexity.
• Develop CI/CD & Deployment Infrastructure: Establish automated tests, pipelines, and staging environments.
• Improve Monitoring & Reliability: Implement observability, alerting, and automated recovery processes.
• Strengthen Security & Compliance: Design secure infra meeting regulatory requirements for financial institutions.
• Build Data Infrastructure: Improve data systems for financial reporting, monitoring, and BI.
• Drive Technical Decisions: Own architectural decisions and infra improvements as the company scales.

Skills

Backend systems

Distributed systems

High-throughput

CI/CD pipelines

Security & compliance

Database design

Asynchronous processing

Ownership mindset

Problem-solving

Job description

Employment Type: Full-Time

Industry: Fintech / Financial Technology

About the Opportunity

We're partnering with a well-funded, high-growth fintech startup that's building next-generation financial infrastructure and payment solutions.

Backed by leading venture capital investors, the company is developing a technology-driven platform designed to modernize how consumers access, manage, and move money.

They're looking for a talented Backend Engineer to take ownership of the reliability, scalability, and architecture of their core financial infrastructure.

This is a high-impact opportunity for an engineer who enjoys building mission-critical systems, solving complex distributed systems challenges, and developing infrastructure that can reliably support significant transaction volumes.

You'll join a small, highly technical engineering team and play a central role in scaling the platform, improving system reliability, and establishing the technical foundations needed to support rapid growth.

What You'll Be Doing

• Own Core Backend Infrastructure: Design, build, and maintain reliable, scalable backend services that power payment processing, financial transactions, and critical business operations.
• Build & Scale Payment Systems: Develop robust infrastructure supporting payment processing, card issuing, financial integrations, and transaction management.
• Ensure Ledger Integrity & Reconciliation: Build and improve systems that maintain financial accuracy across multiple services, including automated reconciliation, transaction validation, and discrepancy detection.
• Scale Distributed Systems: Architect backend services capable of handling significant growth in users, transaction volumes, and system complexity while maintaining performance and reliability.
• Develop CI/CD & Deployment Infrastructure: Establish automated testing, deployment pipelines, and staging environments to improve engineering efficiency and production stability.
• Improve Monitoring & Reliability: Implement comprehensive observability, alerting, anomaly detection, and automated recovery processes to proactively identify and resolve system issues.
• Strengthen Security & Compliance: Design secure infrastructure that meets the requirements of financial institutions, payment partners, and relevant regulatory frameworks.
• Build Data Infrastructure: Improve operational and analytical data systems to support financial reporting, transaction monitoring, risk management, and business intelligence.
• Drive Technical Decisions: Take ownership of architectural decisions, engineering standards, and infrastructure improvements as the company scales.

What We're Looking For

• Strong experience designing, building, and maintaining production-grade backend systems.
• Experience working with distributed systems, microservices, and high-throughput applications.
• Solid understanding of system reliability, scalability, fault tolerance, and performance optimization.
• Experience building or maintaining financial infrastructure, payment processing systems, or other mission-critical transactional applications.
• Strong understanding of database design, data integrity, transaction consistency, and reconciliation processes.
• Familiarity with asynchronous processing, message queues, idempotency, and failure recovery patterns.
• Experience with CI/CD pipelines, automated testing, monitoring, and cloud infrastructure.
• Ability to independently own complex technical projects from architecture through implementation and production deployment.
• Strong problem-solving skills and a proactive, ownership-driven approach to engineering.
• Comfortable working in a fast-paced startup environment with significant autonomy and responsibility.

Nice to Have

• Previous experience in fintech, payments, banking, or financial services infrastructure.
• Experience with card issuing, payment networks, banking integrations, or ledger-based systems.
• Familiarity with financial compliance, security requirements, and auditability.
• Experience designing automated reconciliation and transaction monitoring systems.
• Exposure to data engineering, analytics infrastructure, or regulatory reporting systems.
• Experience scaling infrastructure at an early-stage or high-growth technology company.

Why Join?

• Significant Technical Ownership: Take responsibility for core infrastructure and play a key role in defining the company's backend architecture.
• Challenging Engineering Problems: Work on complex challenges involving distributed systems, financial accuracy, payment processing, and large-scale infrastructure.
• High-Impact Work: Build mission-critical systems that directly support real financial transactions and customer experiences.
• Strong Technical Team: Collaborate with talented engineers and experienced operators with backgrounds in leading technology and financial services companies.
• Early-Stage Opportunity: Join a well-funded startup at an exciting stage of growth, with meaningful influence over engineering decisions and technical direction.
• Competitive Compensation: Attractive compensation package, including meaningful equity upside.
• Career Growth: Help shape the technical foundation of a scaling business while taking on substantial responsibility and ownership.

This is an in-person opportunity based in San Francisco, CA. Candidates must be willing to work on-site and occasionally travel to meet with customers and stakeholders.

Visa sponsorship support is available for qualified candidates.