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I’m a Backend & Platform Engineer specializing in scalable microservices, distributed systems, and high-availability financial platforms. Currently working at Safaricom (Africa’s largest telecom and fintech ecosystem serving 40M+ users), I design and optimize backend systems that power payment processing, cross-market integrations, and secure API platforms . I’ve led performance-driven initiatives including a payment system improvement that contributed ~KES 30M in additional revenue, a Java 8 → Java 21 migration that reduced security vulnerabilities by 90%, and a production database migration from Oracle to PostgreSQL to improve reliability and cost efficiency . I differentiate myself by combining strong system design skills with business impact thinking — I don’t just build services, I build resilient systems that scale, generate revenue, and reduce operational risk.…I’m a Backend & Platform Engineer specializing in scalable microservices, distributed systems, and high-availability financial platforms. Currently working at Safaricom (Africa’s largest telecom and fintech ecosystem serving 40M+ users), I design and optimize backend systems that power payment processing, cross-market integrations, and secure API platforms . I’ve led performance-driven initiatives including a payment system improvement that contributed ~KES 30M in additional revenue, a Java 8 → Java 21 migration that reduced security vulnerabilities by 90%, and a production database migration from Oracle to PostgreSQL to improve reliability and cost efficiency . I differentiate myself by combining strong system design skills with business impact thinking — I don’t just build services, I build resilient systems that scale, generate revenue, and reduce operational risk.

George Leehaney

Back-End Developer, Full Stack Developer, Web Developer, +3

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I’m a Backend & Platform Engineer specializing in scalable microservices, distributed systems, and high-availability financial platforms. Currently working at Safaricom (Africa’s largest telecom and fintech ecosystem serving 40M+ users), I design and optimize backend systems that power payment processing, cross-market integrations, and secure API platforms . I’ve led performance-driven initiatives including a payment system improvement that contributed ~KES 30M in additional revenue, a Java 8 → Java 21 migration that reduced security vulnerabilities by 90%, and a production database migration from Oracle to PostgreSQL to improve reliability and cost efficiency . I differentiate myself by combining strong system design skills with business impact thinking — I don’t just build services, I build resilient systems that scale, generate revenue, and reduce operational risk.…I’m a Backend & Platform Engineer specializing in scalable microservices, distributed systems, and high-availability financial platforms. Currently working at Safaricom (Africa’s largest telecom and fintech ecosystem serving 40M+ users), I design and optimize backend systems that power payment processing, cross-market integrations, and secure API platforms . I’ve led performance-driven initiatives including a payment system improvement that contributed ~KES 30M in additional revenue, a Java 8 → Java 21 migration that reduced security vulnerabilities by 90%, and a production database migration from Oracle to PostgreSQL to improve reliability and cost efficiency . I differentiate myself by combining strong system design skills with business impact thinking — I don’t just build services, I build resilient systems that scale, generate revenue, and reduce operational risk.

Available to hire

I’m a Backend & Platform Engineer specializing in scalable microservices, distributed systems, and high-availability financial platforms. Currently working at Safaricom (Africa’s largest telecom and fintech ecosystem serving 40M+ users), I design and optimize backend systems that power payment processing, cross-market integrations, and secure API platforms . I’ve led performance-driven initiatives including a payment system improvement that contributed ~KES 30M in additional revenue, a Java 8 → Java 21 migration that reduced security vulnerabilities by 90%, and a production database migration from Oracle to PostgreSQL to improve reliability and cost efficiency . I differentiate myself by combining strong system design skills with business impact thinking — I don’t just build services, I build resilient systems that scale, generate revenue, and reduce operational risk.

Skills

Experience Level

Expert

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Language

English

Fluent

Work Experience

Software Engineer at Safaricom PLC

July 1, 2024 - Present

Designed and implemented a scalable payment processing system that improved transaction success rates and contributed to approximately KES 30M in additional revenue. Architected and developed scalable microservices, collaborating with cross-functional stakeholders to expand and localize services across multiple African markets. Built cross-market configuration APIs enabling dynamic GSM access, authentication, M-Pesa security, and third-party integrations. Ensured 99.9% availability and stability for backend systems serving 1,000+ daily active users. Led a Java 8 → Java 21 migration using Open Rewrite, reducing security vulnerabilities by ~90% and improving performance and maintainability. Migrated production databases from Oracle to PostgreSQL, improving reliability, lowering operational costs, and enhancing query performance. Mentored junior engineers and promoted best practices in clean code, testing, and system design.

Platform Engineer (OSS) at Safaricom PLC

November 1, 2023 - May 1, 2024

Provided comprehensive technical support to internal teams and external customers, effectively addressing and resolving various technical issues. Conducted thorough testing and debugging of backend applications, ensuring robustness and reducing system downtime by 25%.

Full-Stack Developer at Haditek

April 1, 2023 - September 1, 2023

Delivered end-to-end features across backend and frontend systems, ensuring responsive, cross-device compatibility. Led and mentored a high-performing team in developing cutting-edge products, resulting in on-time project deliveries and successfully executing project goals.

Full-Stack Developer at Hadi Tek

April 1, 2023 - September 1, 2023

Delivered end-to-end features across back-end and front-end systems, ensuring responsive, cross-device compatibility. Led and mentored a high-performing team in developing cutting-edge products, resulting in on-time project deliveries and successfully executing project goals.