Backend Engineer

About Monida

Monida is an AI-native cross-border payments infrastructure built for cash-to-digital remittances in high-volume migrant corridors. Our customers are migrants in the U.S. sending money home to Mexico, Guatemala, and other countries every month, in cash, at retail locations they already trust, like 7-Eleven and Walmart. We convert that cash into a compliant, near-instant digital payout on the other end.

The Role

We are hiring a Backend Engineer to build and scale MonidaOS Core. You will report to our CTO and work alongside him on the core backend. This is real infrastructure we are actively building out, not a mature, fully-staffed engineering organization. You will own meaningful pieces of the transaction pipeline directly, and your decisions will immediately impact the mobile app our customers use to send money.

What You'll Do

• Money movement: Build and maintain core transaction logic, FX conversion, fee calculation, settlement, refunds, and reversals, on a double-entry ledger with optimistic concurrency control. Every write must be idempotent and safe to retry.
• Payment rail integrations: Integrate and maintain third-party partner APIs across ACH, debit card, cash-in retail networks, and cross-border payout providers (bank deposit and cash pickup), including signed webhooks, status polling, retries, and failure handling.
• Reconciliation: Build the jobs and tooling that match our ledger against partner and bank settlement files, and surface exceptions to Operations and Finance.
• Mobile-first APIs: Design versioned REST/JSON APIs for our Flutter app and web client, token authentication and refresh, tolerance for flaky connections, and backward compatibility across app releases.
• Security: Implement and harden authentication (OTP/MFA, device binding and recovery), rate limiting, encryption of sensitive data, and immutable audit logging.
• Compliance in code: Wire KYC, sanctions (OFAC) screening, transaction limits, and fraud rules into the transaction flow, and support the Compliance team with the data and admin tooling they need.
• Quality and production: Write tests, review code, document APIs, and share production support — including an on-call rotation, for a live system that moves real money.

What You Need

• 3+ years of professional backend development with PHP and Laravel.
• Hands-on experience building money-movement or transactional systems where correctness matters: ledgers or double-entry accounting, idempotency keys, database transactions, locking/concurrency control, and handling duplicate or out-of-order events.
• Proven experience integrating third-party payment, banking, or fintech APIs, including verifying signed webhooks (HMAC), handling retries and timeouts, and reconciling your records against theirs.
• Proven experience building and versioning REST APIs consumed by a mobile client (Flutter, React Native, or native iOS/Android), not only internal or web-only APIs. Be ready to discuss real trade-offs: payload size, sessions on unreliable networks, and backward compatibility across app versions.
• Strong SQL and relational database skills (MySQL/MariaDB), including query optimization, replication, and schema migrations on live data.
• Experience with Redis and queue-based/async processing (Laravel Horizon or an equivalent like Sidekiqi or Celery).
• Solid application security fundamentals: token-based authentication, MFA, rate limiting, secrets management, encryption at rest and in transit, and the OWASP Top 10.
• Comfortable with Docker, CI/CD pipelines, and cloud infrastructure, plus logging and monitoring in production.
• Daily, productive use of AI coding tools (e.g., Claude, Copilot, Cursor), with the judgment to review and test what they produce.
• Professional-level English and Spanish, written and spoken.

Nice to Have

• Experience at a remittance company, money transmitter, payments processor, or neobank.
• Exposure to BSA/AML, KYC/CIP, OFAC screening, transaction monitoring, or PCI-DSS requirements.
• Experience with multi-tenant data isolation in Laravel (global scopes, tenant-aware queries).
• Experience with Filament or another Laravel-based admin panel framework.
• Experience with Laravel Reverb or WebSockets for real-time updates.

What We Offer

• Fully remote, flexible hours within the required U.S. time-zone overlap.
• A ground-floor seat at a fast-moving, AI-native fintech. You will help shape the actual architecture, not inherit someone else's.
• Direct access to leadership. Decisions move fast here.
• Employee Stock Options.

How to Apply

Apply directly through this listing with your resume and, if you have one, a GitHub or portfolio link. In a few sentences, tell us about the most complex payment or money-movement integration you have built and one thing that went wrong in production.

Salary: Starting from $40,000.00 per month

Benefits

• Flexible hours

Workplace

• Remote employment