Software Engineering Attaché, Research and Development
Attain Enterprise Solution Ltd · Nairobi, Kenya
I work on the R&D team, building core backend service logic in Java and driving improvements to performance, concurrency and reliability across our PostgreSQL and SQL Server data layers.
- 01Service layer and business logic
- Build backend service logic in Java with explicit transaction boundaries, so multi-step operations commit fully or roll back cleanly without leaving partial state.
- 02API contracts and edge validation
- Validate input at the service boundary and return predictable error payloads, so callers get consistent behaviour and bad data is rejected before it reaches the database.
- 03Cross-database portability
- Ported enterprise schemas and constraints between PostgreSQL and SQL Server, resolving dialect differences in data types, constraint behaviour and SQL syntax so the system runs on both engines.
- 04Versioned schema migrations
- Introduced repeatable, version-controlled schema migrations with Flyway, giving every environment a reproducible database state and putting structural changes through code review.
- 05Concurrency on critical writes
- Isolated and resolved race conditions on critical write paths using explicit row-level locking and tuned transaction isolation levels, matching the control to how often conflicts occur.
- 06Query profiling and index tuning
- Diagnosed slow queries from execution plans, then refactored multi-table joins and tuned indexes to improve read performance through better data access.
