Hosam A.

Helped the team and the company become more productive through knowledge sharing, code reviews, pair programming, writing reusable libraries, analysing performance bottlenecks, improving the reliability and speed of the CI pipeline, engineering architectural solutions, fixing bugs and flaky tests, increasing test coverage, and leading a team to deliver vital projects. My contract was renewed 4 times in recognition of the value I added. Among many noteworthy achievements, I helped: • Lead a team to deliver high-quality features within a constrained timeline, including customer-facing APIs • Lead the development effort to support a crucial infrastructure migration • Engineer architectural solutions for cross-cutting concerns across multiple services • Build tools to highlight performance bottlenecks in production, along with other tools to analyse them in development environments, resulting in >40% reduction in overall database traffic • Analyse and fix long-standing production issues that were hard to reproduce • Extend and supplement multiple open-source libraries, such as Rails' ActiveRecord, Fog, Open Telemetry, RSpec, RuboCop, and others, with features, bug fixes, and performance improvements • Measure, analyse, and optimise slow test cycles on developer machines, resulting in tests starting 90% faster with a direct impact on team productivity • Reduce the running time for CI pipelines by 75% while reducing network and processing costs at the same time • Build a tool to analyse CI pipeline performance and identify bottlenecks • Configured Gitlab to report information about test failures and test coverage. Making this information visible in merge requests helped the team increase test coverage. • Improve testability by configuring local development replicas of some production services

Challenged to improve a legacy codebase that had ~100k Ruby LOC • Analysed the system and drafted short and long-term plans with measurable results • Created CI pipelines and wrote hundreds of automated test cases including end-to-end tests • Integrated error monitoring tools and created dashboards for performance and error monitoring • Provided production support and wrote support scripts to handle frequent requests • Successfully fixed bugs and delivered new features across multiple applications with a 96% deployment success rate • Wrote wiki-style documentation for the apps’ architecture, infrastructure, deployment processes, and major design considerations • Produced improved reports that enabled more accurate billing to B2B customers • Improved performance by an order of magnitude, decreasing the 99th percentile from minutes to seconds • Identified thousands of dollars in cost savings