Aggrey Lelei Resume | Head Of Tech

Aggrey Kiplimo Lelei

Head Of Technology

Professional Summary

Head of Technology and Senior Software Engineer with 8+ years of experience leading teams and building scalable distributed systems. After early career work in Android and ERP development at Smart Web Kenya, I joined Tiret Resorts in 2020 to architect a cloud-native NGO logistics platform from scratch. Following a major expansion pitch that drove revenue and regional adoption, I was promoted to Head of Technology to lead engineering strategy and platform scale-out. Today, I direct a small engineering team operating Spring Boot–based event-driven services that supports multiple concurrent users at peak with sub-150 ms latency while improving NGO productivity by ~55%. My focus centers on resilient backpressure-aware processing, deep system observability, and integrating Agentic AI to power agentic RAG workflows grounded in live data.

Experience

Head of Technology

Tiret Resorts • Kenya

March 2023 - Present

Promoted to Principal Lead during platform scale-out and growing engineering needs, owning technical strategy, system architecture, and delivery while expanding managerial scope across recruiting, mentorship, and stakeholder alignment.

Technical Strategy & Architecture: Owned platform direction and system design for scale, improving NGO productivity and engagement by ~55% and increasing regional coordination impact through reliable platform execution.
Platform Expansion & Outcomes: Pitched and delivered a major platform expansion that drove revenue growth, improved customer satisfaction, and increased regional engagement through clearer workflows and stronger reliability.
People Leadership: Led a team of engineers; handled recruiting, onboarding, mentoring, and performance support while maintaining high engineering throughput and quality.
Performance & Scale: Supported multiple concurrent users with sub-150 ms latency at peak, emphasizing fast user experiences and resilient operations.
Stakeholder & Shareholder Management: Took ownership of cross-functional alignment — translating business goals into technical plans, leading shareholder discussions, and communicating trade-offs, risk, and delivery timelines with clarity.
Agentic Context Engineering: Integrated Embabel to enable advanced agentic and retrieval-augmented workflows grounded in live system data, strengthening operational decision-making and accelerating support/coordination loops.

Senior Software Engineer

Tiret Resorts • Kenya

January 2020 - Feb 2023

Architected and delivered a cloud-native NGO communication and logistics platform from inception to production, owning system design, backend architecture, testing strategy, and long-term maintainability while leading day-to-day engineering execution.

Spring Boot Architecture Design: Designed a modular Spring Boot backend using layered architecture (Controller–Service–Repository), RESTful APIs, JPA/Hibernate, and secure authentication flows. Established clean package structures, configuration management, and scalable deployment foundations.
Platform from Scratch: Built core coordination, messaging, and logistics workflows end-to-end, translating business requirements into resilient domain models and production-grade backend services.
Testing & Code Quality: Implemented unit and integration testing (JUnit, Mockito), enforced code reviews and standards, and improved reliability through structured validation and regression coverage.
Maintenance & Optimization: Owned ongoing system maintenance, refactoring legacy modules, resolving production issues, improving performance, and ensuring long-term codebase sustainability.
Team Leadership: Mentored and unblocked junior engineers, improved development workflows, and maintained delivery discipline across the engineering lifecycle.

Android Software Engineer

Smart Web Kenya • Nairobi, Kenya

September 2017 - December 2019

Began career building and shipping production-grade Android applications, delivering end-to-end mobile features, integrating backend APIs, and ensuring stable releases for real-world client deployments.

End-to-End Android Development: Designed and implemented native Android applications using Java/Kotlin, following MVVM architecture, clean code principles, and modern Android SDK best practices.
API Integration & Data Handling: Integrated RESTful APIs, implemented JSON parsing, managed local persistence (Room/SQLite), and ensured efficient state management for reliable offline/online behavior.
UI/UX & Performance Optimization: Built responsive, user-friendly interfaces using XML layouts and Android components, optimized rendering performance, and reduced crashes through structured debugging and profiling.
Release & Production Stability: Managed build variants, signing configurations, Play Store deployment processes, and strengthened error handling to maintain stability in live environments.
Engineering Foundations: Developed strong fundamentals in debugging, performance tuning, modular code organization, and disciplined feature delivery forming the base for later backend and distributed systems work.

Technical Skills

Languages:Springboot (Java + Kotlin), Python, TypeScript, Go

Enterprise AI Orchestration:Embabel, LangGraph

Workflow Orchestration:Temporal, Restate

Event Streaming:Kafka, RabbitMQ

Cloud & Infrastructure:AWS (S3, EKS, MSK, ElastiCache, RDS, ECS, SQS, CloudWatch), Azure Cloud, Docker, k8s, Google Cloud Platform

Secret Management:HashiCorp Vault

Monitoring:LangFuse, Prometheus, Loki, Tempo, Alloy, Grafana

Projects

SparrowX - Enterprise Agentic Knowledge | Internal Company Directory

2025 – Present

📁 Source Code

An enterprise agentic knowledge system for engineering organizations, combining durable multi-step AI orchestration with structured company context, document intelligence, grounded reasoning, and self-referential developer onboarding.

Durable agentic orchestration: Built the Agentic Service around Embabel for intent interpretation, iterative planning/review, tool selection, and synthesis, with Temporal providing durable workflow execution, retries, cancellation, human approval gates, checkpoints, and crash recovery.
Enterprise knowledge architecture: Designed gRPC-based Agentic, Internal, and Document services; Internal models teams, services, ownership, repositories, and onboarding paths, while Document provides ingestion, retrieval, and evidence generation for unstructured engineering knowledge.
Grounded retrieval & context engineering: Implemented hybrid retrieval across Elasticsearch and Qdrant, evidence graph construction, citation and grounding verification, and multi-hop reasoning across structured internal data and technical documents.
Production infrastructure & LLMOps: Built shared CQRS infrastructure, multi-tenant governance, PostgreSQL/Neo4j/MinIO-backed services, OpenTelemetry observability with Tempo, Prometheus, Loki, and Grafana, plus Langfuse for agent tracing, cost/latency analysis, prompt management, and evals.

Credentials

• IBM Blockchain Developer - Mastery Award (2018)• Bachelor's Degree in Computer Science - Jomo Kenyatta University Of Agriculture And Technology, Nairobi (2017)