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# Full-Stack Engineer. Merchant Portal & Checkout Layer

- **Company:** Aya Global LLC
- **Location:** United States (Remote available)
- **Experience:** Expert
- **Contract:** Permanent contract
- **Skills:** Application Programming Interfaces (APIs), Amazon Web Services, Software as a Service, Cloud Engineering, Data Architecture, PostgreSQL, Node.Js, Role-Based Access Control, Standard Sql, Data Streaming, TypeScript, Data Logging, ReactJS, Kubernetes, Apache Kafka, ISO 8583, Restful APIs, Dynatrace, Pagerduty
- **Published:** September 21, 2026
- **Apply:** https://www.indeed.com/viewjob?jk=276d81c7d9ed4071

## About the Role

* 4+ years full-stack experience with React (TypeScript) and Node.js (Express or Fastify); strong SQL and PostgreSQL skills
 * Experience building multi-tenant SaaS platforms with complex role-based permission models
 * Comfort designing and evolving high-concurrency transaction systems; understanding of idempotency, distributed locking, and eventual consistency
 * Familiarity with event streaming (Kafka or Pub/Sub) and asynchronous processing patterns
 * Cloud-native experience on GCP or AWS; understanding of container orchestration (Kubernetes, Cloud Run) and CI/CD pipelines
 * Strong ownership ethos: you don't wait to be told what's broken, you find it and fix it
 * Bonus: experience in payments (ISO 8583, EMV, QR code standards), loyalty platforms, or POS integrations

## Description

You will own two of the most consequential layers of the Aye platform: the merchant portal that surfaces real-time payments, loyalty, and CRM intelligence to retailers across APAC; and the checkout layer that routes and reconciles complex, multi-vertical transaction logic: abstracting regulatory, currency, and scheme complexity into a seamless experience for merchants and consumers. You're self-driven, take end-to-end ownership, and thrive in a team that ships fast and iterates constantly., * Build and evolve the merchant portal: real-time analytics dashboards, loyalty programme configuration, multi-location CRM views, and role-based access control across merchant hierarchies

 * Own the checkout layer: design and implement the transaction routing engine that handles multi-scheme payments (QR, card, biometric), multi-currency reconciliation, tax logic, and vertical-specific checkout flows (F&B, fuel, transit, retail)
 * Design RESTful and event-driven APIs (Kafka, Pub/Sub) for merchant integrations, webhook delivery, and real-time event streaming
 * Build multi-tenant, multi-region data architecture that enforces merchant data isolation while supporting cross-market reporting
 * Instrument end-to-end observability: distributed tracing (OpenTelemetry), structured logging, latency SLA monitoring, and real-time alerting via PagerDuty or equivalent
 * Contribute to continuous UX improvement: identify friction in merchant workflows through usage analytics, propose and ship improvements iteratively