Backend Engineer (Node.js, GCP)

We are hiring a Backend Engineer to build, maintain and scale the server-side systems that power BuyQuick. Our backend handles bill payments, wallet ledgers, marketplace orders, escrow holds and releases, bulk purchases, bank transfers, push notifications and integrations with payment and utility providers. You will work on our Node.js and TypeScript backend running on Google Cloud Platform, using Firebase Cloud Functions, Firestore, Cloud Tasks and Firebase Storage. You will also help build the services behind our next major product: an AI chat assistant that lets business customers pay bills by message. Your code will move real money for real people. We need someone who writes correct, defensive, well-tested code and understands idempotency, race conditions and data integrity in financial systems. Key responsibilities: • Design, build and maintain secure REST APIs and backend services in Node.js and TypeScript. • Implement and maintain wallet, ledger, escrow and transaction logic with strong consistency and full audit trails. • Integrate and maintain payment, transfer and utility provider APIs, including webhooks, signature verification and reconciliation. • Build reliable background jobs with Cloud Tasks and scheduled functions (for example, bulk purchases, retries and settlements). • Model Firestore data, design indexes and optimise queries for performance and cost. • Write unit and integration tests and take part in code reviews. • Monitor production with logging, alerts and error tracking, and help resolve incidents quickly. • Apply security best practices: input validation, authentication and authorisation, secrets management and protection of customer data under the Nigeria Data Protection Act 2023. • Document APIs and technical decisions clearly. Nice to have: • Experience with double-entry ledgers or reconciliation systems. • Experience with PostgreSQL, Redis, Pub/Sub or Cloud Run. • Experience integrating LLM APIs or building chat-based services. • Knowledge of CBN guidelines on KYC and payments, or PCI DSS principles. • Open-source contributions. Department: Engineering Experience: 3 years or more in backend development Education: OND, HND, Bachelor's degree or higher in Computer Science, Software Engineering or a related field (or equivalent practical experience) Application deadline: 31 October 2026 About BuyQuick: BuyQuick is a Nigerian fintech platform that brings everyday payments into one wallet. Customers use BuyQuick to buy airtime and data, pay electricity, cable TV, internet and school fees, buy and sell safely through our free escrow marketplace, make bulk purchases from a single Excel upload, and transfer earnings instantly to any Nigerian bank. Every transaction comes with a QR-verifiable receipt. BuyQuick is available on Android, iOS and the web at buyquick.ng. BuyQuick is an equal opportunity employer. We welcome applicants from every state, background, gender and ability. BuyQuick will never ask you to pay any fee at any stage of recruitment. If anyone asks you for money in our name, please report it to customer@buyquick.ng.