Promise Oghenevwefe

Promise Oghenevwefe Senior Backend Developer with 5 years of experience architecting and delivering scalable web applications using Javascript, Typescript, PHP, Go, and Python. Deep expertise in database design (PostgreSQL, MySQL, Mongo), event-driven architectures, and production observability through comprehensive logging and monitoring systems. Adept at working across the entire stack. SKILLS ●​ ●​ ●​ ●​ ●​ ●​ Languages​ ​ ​ Frameworks/Libraries​ Databases​ ​ ​ Cloud & Devops​ ​ Testing​ ​ ​ AI/ML​ ​ ​ ​ ​ ​ Typescript Javascript, PHP, Golang, Python Nestjs, Expressjs, Laravel, Django, FastApi, Gin Postgres, MySQL, MongoDB, Redis. Docker, AWS, CI/CD, Heroku, Vercel, Digital Ocean, Kafka, Prometheus, Grafana Jest, Unit Testing, Cypress, Integration Testing RAG Architecture, Vector Embeddings (sentence-transformers), Semantic Search, ChromaDB, OpenAI API, Prompt Engineering EXPERIENCE Cloudax | Senior Backend Engineer February 2024 - Present | Nigeria ●​ Architected and deployed multiple backend microservices for a SaaS platform using NestJS, Redis, and Docker, emphasizing clean architecture, data consistency, and maintainability across distributed systems. ●​ Integrated blockchain smart contracts with a NestJS backend to enable secure, on-chain transactions. ●​ Implemented an authentication microservice using JWT, OAuth2, and refresh token rotation, supporting concurrent sessions and seamless inter-service authentication. ●​ Optimized API performance and reduced latency by implementing strategic Redis caching, database indexing, and Prisma query optimization; established comprehensive observability through real-time logging and proactive monitoring. ●​ Developed RESTful APIs and middlewares, applied Redis caching and Prisma query optimization to boost response times, and integrated real-time logging for observability. ●​ Integrated third-party payment gateways (Paystack, Flutterwave, Interswitch) for transaction processing, implementing webhook handlers, idempotency mechanisms, and reconciliation systems. Scandiweb | Fullstack Developer May 2021 - Dec 2023 | Remote (Latvia, India, UK) Delivered solutions for international clients across 3 countries (UK, India, Latvia) ●​ Engineered efficient GraphQL resolvers and optimized API queries, reducing network overhead and enhancing data handling for React-based PWA frontends. ●​ Improved application responsiveness and stability by diagnosing and resolving critical backend performance bottlenecks through in-depth profiling and query optimization. ●​ Led end-to-end development of new full-stack features using PHP, Magento 2, Laravel, React, and GraphQL, enforcing high standards for code quality and maintainability. ●​ Mentored and guided junior developers through detailed code reviews, actively promoting clean architecture and engineering best practices. ●​ Led cross-functional troubleshooting with frontend and QA teams to resolve complex, full-stack issues and maintain a consistent user experience. TechclubNg | Fullstack Developer/Instructor / Freelancer Dec 2019 - Present | Nigeria ●​ Spearheaded the development of a web application for 5,000+ users, launching a marketplace and amenities portal that increased user engagement by 35%. ●​ Led backend engineering teams in building high-availability e-commerce backends (MySQL, Postgress, Node, Laravel), reliably processing 500+ monthly orders with 99% uptime. ●​ Engineered and launched a full-stack artisan hiring platform using Laravel and React, driving platform adoption to over 2,000 user registrations in the first year. ●​ Mentored and trained a cohort of 20+ interns in full-stack development principles (Node.js, PHP, Laravel, Python/Django), contributing to an 80% job placement rate. EDUCATION University of Benin​ ​ B.Sc Computer Science ​ ​​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nigeria Oct 2018 PROJECTS ●​ Eco Reward - (B2B) Reward and Loyalty Platform (Nestjs, PostgreSQL)​ Built a B2B platform that enables merchants to purchase and distribute Eco Tokens as customer rewards. Users can redeem tokens on the Eco Store or with affiliated merchants, creating a connected ecosystem that drives loyalty and engagement. The platform also includes gift card functionality and allows merchants to run custom campaigns to boost user participation and retention. ●​ Espees Enterprise - Multi-Signatory Payment Processing Platform (NestJS + PostgreSQL): Built a secure payment platform enabling multi-party transaction approvals with RBAC. Implemented transaction state management, audit logging, and idempotent payment processing with PostgreSQL transactions to ensure data consistency. ●​ System Rate Limiter (Go):​ Designed and implemented rate-limiting algorithms (Fixed Window, Sliding Window, Token Bucket) with configurable limits. ●​ Activity Tracker (NestJS + Prisma):​ Developed event-driven activity logging system capturing user actions across distributed services. Leveraged Kafka for real-time streaming, ClickHouse for analytical queries (80% faster than PostgreSQL), and Grafana dashboards for observability and behavioral analysis. ●​ RAG-Powered Document Q&A System (Python):​ Built a Retrieval-Augmented Generation (RAG) system enabling semantic document Q&A by embedding and storing document chunks in ChromaDB and generating context-aware answers using OpenAI GPT. ●​ Role-Based Access Control System (Node.js):​ Developed a permission-based access model supporting CRUD and granular resource access for enterprise REFERENCES - Available on request.