Joseph Kimenyu

Building software that
actually ships

I'm a Fullstack & AI Engineer with 5+ years of experience designing and building production-grade systems. My work spans backend APIs, mobile applications, and AI-powered tooling — with a strong preference for clean architecture, performance, and developer experience.

Based in Nairobi, I've worked with teams across Rwanda, the US, and Kenya, shipping software for fintech, SaaS platforms, and e-commerce. When I'm not building, I'm writing about the engineering decisions that go into it.

Nairobi, Kenya · Open to remote worldwide

AI Engineer — LLM Training & Evaluation

Turing

Jun 2024 – Dec 2025

USA (Remote)

Designed structured datasets and multi-turn conversations for LLM training. Evaluated model outputs for correctness, performance, and safety. Applied systematic reasoning and structured feedback to improve model reliability.

LLM dataset designModel evaluation & safetyDistributed team collaboration

Fullstack Developer

Mediacrest Digital Limited

Apr 2024 – Nov 2025

Nairobi, Kenya

Developed end-to-end web applications using Node.js, Express, and React. Designed and deployed scalable REST APIs integrated with frontend dashboards. Managed deployments on AWS and Azure environments.

Node.js + React applicationsAWS & Azure deploymentsThird-party API integrations

Fullstack Developer

Order is Ready

Feb 2022 – May 2024

Rwanda (Remote)

Designed and maintained scalable RESTful APIs using Node.js and Go. Architected PostgreSQL data models and optimized queries, improving API response times by ~20%. Deployed containerized services using Docker.

Node.js & Go APIs~20% API performance improvementDocker containerization

Fullstack Developer

Freelance

Jan 2022 – Present

Remote

Built secure, scalable backend systems using Node.js, Go, and Python. Designed RESTful APIs consumed by web and mobile applications. Implemented JWT authentication and RBAC authorization models.

Multi-stack deliveryMobile & web APIsJWT/OAuth security

Backend Engineering

Node.jsExpressGo (Chi, net/http)PythonFastAPIDjangoREST APIsMicroservicesRate LimitingClean Architecture

Frontend & Mobile

React.jsNext.jsFlutterTypeScriptJavaScript (ES6+)Tailwind CSSRiverpod

Databases

PostgreSQLMySQLMongoDBDynamoDBMSSQLRedisSchema DesignQuery Optimization

Cloud & DevOps

AWS (EC2, S3, IAM)AzureDockerLinuxCI/CDRenderVercelNeon

Auth & Security

JWTOAuth 2.0RBACSecure API Designbcrypt

AI & LLM

OpenAI APIFunction CallingPrompt EngineeringAgentic WorkflowsLLM EvaluationFastAPI AI Services

Engineering Practices

Agile/ScrumSystem DesignSwagger/OpenAPIUnit & Integration TestingGitCode Reviews

ALX Africa

Backend Software Engineering · AWS

2022–2023

Africa Nazarene University

Bachelor of Science in Finance

2018–2022

Kenya