JOSHUA OKELLO
Senior Full Stack Developer
Nairobi, Kenya
- |-Portfolio
LinkedIn Profile URL
PROFESSIONAL SUMMARY
Self-starting Full Stack Developer with 5+ years of experience building fast, reliable web
applications in agile environments. Proven expertise in React, Node.js, and relational
databases with a pragmatic, customer-first approach. Strong team player with experience
collaborating across functions to deliver high-quality solutions on time. Committed to writing
clean, maintainable code following SOLID principles and best practices.
TECHNICAL SKILLS
•
•
•
•
•
•
•
•
Frontend: React, JavaScript, TypeScript, HTML5, CSS3, Tailwind, Next.js
Backend: Node.js, Spring Boot, RESTful APIs, Microservices
Databases: PostgreSQL, MySQL, MongoDB
Programming Paradigms: Object-Oriented Programming, Functional Programming,
SOLID Principles
Design Patterns: Factory, Singleton, Observer, MVC, Repository
API Technologies: RESTful, GraphQL
DevOps & Tools: Git, Docker, CI/CD Pipelines, Agile/Scrum
Testing: Jest, Unit Testing, Integration Testing
PROFESSIONAL EXPERIENCE
Software Engineer (Full Stack)
Fin Africa | April 2024 - Present
•
•
•
•
•
•
Developed real-time payment processing system using Node.js and React, achieving
99.9% uptime and 30% faster transactions
Implemented TypeScript across both frontend and backend to improve code quality
and reduce bugs by 40%
Designed and built microservices architecture following SOLID principles, improving
system scalability and reducing downtime by 30%
Enhanced database performance by 50% through PostgreSQL query optimization and
indexing
Led cross-functional collaboration between product, design, and QA teams to deliver
customer-focused solutions
Mentored junior developers and championed code quality through pair programming
and code reviews
Software Engineer
Tridens Technology | May 2022 - April 2024
•
•
•
•
•
•
Built responsive web applications using React and TypeScript, improving user
experience and system reliability
Developed backend services with Node.js, creating efficient APIs that reduced
response times by 45%
Applied object-oriented design patterns to create maintainable, modular code
architecture
Collaborated with cross-functional Agile teams to deliver projects on time, reducing
development cycles by 40%
Created reusable component libraries that accelerated development across multiple
projects
Implemented GraphQL APIs, improving data fetching efficiency and frontend
performance
Quality Assurance Engineer
Copia Global | February 2021 - April 2022
•
•
•
•
Designed and executed comprehensive test plans for Node.js and React applications
Implemented automated testing using Jest, increasing defect detection rates by 25%
Collaborated with developers to ensure code quality and adherence to SOLID
principles
Streamlined testing processes, reducing manual testing time by 25% and improving
release cycles
Full-Stack Developer
Stemscence | June 2020 - January 2021
•
•
•
•
•
Built scalable web applications using React, Node.js, and MongoDB, reducing load
times by 40%
Implemented TypeScript across the stack, reducing type-related bugs by 35%
Designed PostgreSQL database schemas optimized for application performance
Integrated third-party services and APIs, enhancing application functionality
Applied design patterns and SOLID principles to create maintainable, extensible
codebase
Backend Engineer
WorkFleek Ltd | February 2020 - May 2020
•
•
•
Developed backend services for Prism Health application using Node.js and
PostgreSQL
Collaborated with frontend team to design and implement RESTful APIs
Implemented database optimizations that improved query performance by 35%
Software Engineering Intern
Sendy Ltd | April 2019 - September 2019
•
•
•
Assisted in developing full-stack logistics solutions using JavaScript frameworks
Gained hands-on experience with Agile methodologies and cross-functional
collaboration
Contributed to database design and implementation using MySQL
EDUCATION
Bachelor of Science in Software Engineering
Kisii University | 2016 - 2020
Second-Class Honors
CERTIFICATIONS
•
Bachelor of Science in Software Engineering
LANGUAGES
•
•
English (Fluent)
Kiswahili (Fluent)
