Lead / Senior Backend Engineer – Public Payment Gateway & Banking Rails

Company Description JcoTeck is a leading technological company in Africa focused on delivering sustainable ICT and engineering solutions to startups, small and medium enterprises, and large organizations. The team leverages cutting-edge technologies to help businesses establish a strong online presence, increase profitability, and stay competitive. JcoTeck’s services span visually appealing design, including graphics, branding, and UI/UX, as well as rapid responsive web and mobile application development. The company also provides IoT and embedded systems solutions, AI and robotics services, digital marketing campaigns, and digital training. This environment offers technology professionals the opportunity to work on diverse, innovative projects with impact across multiple industries.

Tech Stack: Node.js 24, NestJS (Fastify) , TypeScript, PostgreSQL 18, Docker, AWS (KMS, EKS/ECS), moov/ach, SFTP/PGP, REST/Webhooks

About the Role

We are seeking an experienced Lead / Senior Backend Payments Engineer to architect and scale our public-facing payment gateway and core processing platform.

This platform serves external merchants, partners, and clients who integrate via public-facing APIs, SDKs, and merchant dashboards, while connecting directly to international acquiring networks and sponsor banks (ODFIs) without third-party aggregator lock-in.

In this role, you will own the technical blueprint of our external payment workflows: from high-throughput merchant intake APIs, cryptographic bank vaults, and real-time ledger accounting, to scheduled banking cutoffs, settlement pipelines, and merchant webhook delivery. You will define development standards, unblock architectural hurdles, mentor junior and mid-level engineers, and fast-track product delivery.

What You Will Do

Architect Public-Facing Gateway APIs: Build secure, developer-friendly, multi-tenant public APIs (REST/JSON) that external merchants consume for transaction initiation, payment validation, and tokenized checkouts. Drive Banking & Acquiring Connectivity: Direct the technical integration with international acquiring networks (e.g., switches, gateway APIs) and sponsor banks (ODFIs) using SFTP with PGP encryption and ISO-compliant protocols. Implement Core Processing Infrastructure: Build resilient backend microservices using Node.js 24 , NestJS with the Fastify adapter (@nestjs/platform-fastify), and PostgreSQL 18 , maintaining clean separation across API, Worker, and Filer runtime processes. Scale Batch Cutoff Engines: Oversee our scheduled cutoff engine interfacing with containerized moov/ach services to assemble, validate, and dispatch 94-character fixed-width Nacha files. Enforce Immutable Ledger Systems: Expand an append-only, double-entry financial ledger modeled strictly in integer cents (BIGINT), ensuring $\sum \text{debits} - \sum \text{credits} = 0$ across all transaction states. Secure the Financial Vault: Maintain database-level schema isolation and envelope encryption (AES-256-GCM via DEK/KEK backed by AWS KMS) to securely tokenize and dereference sensitive bank credentials. Technical Mentorship & Execution Velocity: Break down product roadmaps into precise milestones (including return code automation R01–R85, NOC handling, settlement reconciliation, and webhooks), review code, mentor mid/junior engineers, and accelerate delivery. Collaborate Across Full-Stack Surfaces: Partner with frontend/full-stack teams working in Next.js to deliver client checkout components, merchant admin consoles, and signed webhook notification loops.

Who You Are

Hands-on Payments & Gateway Background: Proven experience building or scaling commercial payment gateways, acquiring processors, or payment service providers (PSPs) interfacing with banking networks. Bank & Protocol Integration Knowledge: Practical familiarity with banking clearing rails (ACH/Nacha WEB debits, return codes R01–R85, NOCs) or card processing switches (ISO 8583, BIN routing tables, authorization workflows). NestJS & High-Performance Node: Deep hands-on experience with TypeScript, NestJS, Fastify, and asynchronous worker queues (BullMQ/Redis). Relational Database & Ledger Design: Strong PostgreSQL capabilities, including isolated database schemas, row-level locking (FOR UPDATE SKIP LOCKED), constraints, and multi-currency/integer-cent double-entry ledgers. Cloud & DevOps Rigor: Track record running containerized services using Docker, Docker Compose, and AWS services (AWS KMS, IAM, ECS/EKS). Technical Envisioning & Leadership: Natural ability to translate high-level business goals into clean technical specs, guide less experienced developers through complex banking mechanics, and maintain high build momentum.

Nice to Have

Experience building public developer tooling (API documentation, developer portals, client SDKs, or signed webhook retry engines). Familiarity with international payment processors and acquiring platforms (such as Fiserv, Adyen, Chase Paymentech). Direct experience running open-source banking software like moov/ach. Knowledge of compliance frameworks such as Nacha Third-Party Sender (TPS) requirements or PCI DSS operational data isolation.

How to Apply

Qualified candidates should submit their CV/Resume and Portfolio URL directly to hr@jcoteck.com.ng with the subject line:

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