Senior Ruby on Rails Engineer
Languages: Spanish (native), English (professional)
Location: Colima, Mexico
Education: Systems Engineering (Bachelor’s)
Availability: Remote / Hybrid
Email: cesargomez89@gmail.com
LinkedIn: https://www.linkedin.com/in/cesargomez89
GitHub: https://github.com/cesargomez89
Senior Ruby on Rails Engineer with 12+ years of experience architecting, scaling, and modernizing backend systems across high-growth SaaS, fintech, and communications platforms. Deep expertise in distributed systems, service decomposition, performance optimization, and upgrading legacy codebases. Known for reducing operational bottlenecks, improving system reliability, enforcing engineering standards, mentoring teams, and delivering stable, well-tested software. Strong collaborator experienced in multi-service platform development, CI/CD automation, and developer tooling in fast-paced product environments.
Backend: Ruby, Ruby on Rails, Sinatra, REST APIs, Microservices, Nest, Kafka, SQS, Redis
Frontend: JavaScript, React, Hotwire, Turbo, Stimulus, Tailwind, HTML, HAML, CSS, SASS
Testing: RSpec, Minitest, Capybara, TDD/BDD, Static Analysis
Databases: PostgreSQL, MySQL, DynamoDB, ElasticSearch
DevOps: AWS, Docker, CI/CD (GitLab CI), Heroku, NGINX
Architecture: Domain Driven Design, Layers, Rails Engines, Packwerk, Performance Profiling
Tools: Git, Vim, Tmux, Observability & Monitoring
2023–Present
- Led the design and evolution of a multi-channel communication platform (SMS, voice) used by thousands of teachers and parents; built with Kafka, Rails, and distributed services.
- Scaled SMS delivery throughput from 1,200/min → 20,000/min by implementing a Kafka-backed messaging pipeline and optimizing delivery fan-out strategies.
- Upgraded a critical legacy Rails system and integrated it into the new Kafka architecture, enabling reliable message flow across multiple services.
- Reduced manual onboarding from days to hours by automating A2P 10DLC, campaign registration, and Twilio/Bandwidth profile provisioning (API-driven workflows).
- Built a data ingestion and provisioning pipeline (DB, SFTP, CSV) using Nest.js to validate, transform, and sync district staff data across internal products.
- Created a production-like Docker environment simulating distributed services, Kafka brokers, and API gateways, improving onboarding and debugging.
- Increased coverage of a legacy codebase from 0% → 75% and maintained 90%+ coverage in new services through CI-enforced test detection and pre-commit hooks.
- Automated GitHub releases and changelog generation using conventional commits.
- Built internal dashboards to manage Twilio and Bandwidth profiles at district scale, automating registration, auditing, and compliance workflows.
2022–2023
- Developed a cross-device donation widget using vanilla JavaScript and Web Components, improving accessibility.
- Integrated Stripe and PayPal with country- and currency-aware routing.
- Improved backend stability by strengthening test coverage and replacing flaky system tests with Cuprite-based E2E testing.
2021–2022
- Implemented ElasticSearch across high-traffic search, catalog, and order flows, reducing DB load and improving response times.
- Designed and shipped the company’s first Rails Engine, establishing clean domain boundaries.
- Built a robust ETL pipeline for third-party order synchronization, reducing integration failures.
- Migrated frontend from Webpacker to Importmaps, reducing CI build times and simplifying assets.
- Optimized GitLab CI pipelines through job deduplication and better parallelization.
- Developed real-time user experiences using Hotwire and ActionCable.
2019–2021
- Delivered features and modernization across multiple client projects in an agile consultancy environment.
- Improved legacy systems through refactoring, updated testing, and Rails upgrades.
- Strengthened CI reliability and standardized engineering practices across products.
2020–2021
- Increased test coverage from 60% → 86%, reducing regressions.
- Upgraded Rails 4 → Rails 6 and added modern tooling.
- Added parallel testing, static analysis, and CI improvements.
- Built internal dashboards and modular Rails Engines.
2019–2020
- Built a fraud-scoring microservice for high-volume lending workflows.
- Integrated scoring with core apps using API contracts and documentation.
- Improved engineering standards, documentation, and code quality.
2013–2019
- Promoted from Junior → Senior Developer while leading multiple long-term client projects.
- Modernized legacy systems, improved architecture, and established internal engineering standards.
- Built CI/CD pipelines, monitoring strategies, and performance improvements.
2017–2019
- Led backend engineering for a high-transaction prepaid card exchange platform.
- Integrated Sift Science for fraud detection, reducing false positives.
- Delivered major features while reducing technical debt.
- Collaborated with product and operations teams on workflows and roadmap planning.
2013–2017
- Migrated Rails 3 → Rails 4, improving performance and maintainability.
- Moved infrastructure from Rackspace → AWS, increasing reliability.
- Implemented monitoring, structured logging, and automated backups.
- Created architecture documentation and engineering standards adopted across teams.