Hire principal / staff freelance Ruby on Rails developers

I'm a programmer living in Belgium. Passionate about building beautiful things through craftsmanship. --- EXPERIENCE --- Senior Developer PAUWELS CONSULTING ⋅ [ 2022 – PRESENT ] • Integrated Single Sign-On (SSO) with Keycloak for Belgian cities and municipalities. • Set up and maintained a background processing system to fetch, parse, anonymize, and store millions of emails daily • Migrated a actively used FinTech application from PostgreSQL to MariaDB. Founder & CEO FRONTIER ⋅ [ 2017 – PRESENT ] • Developed and implemented digital strategies for over 50 SMEs. • Set up, configured, and managed a fleet of servers tailored to customers' projects with Kamal. • Built a gem to create great-looking forms with Bootstrap • Developed an in-house CMS with a wide range of features, including live preview, revision history, a form builder, an email marketing tool, impersonation, a media library, ACL, SSO, over 100 integrations, … Senior Developer DPG MEDIA ⋅ [ 2019 – 2019 ] • Modernized a Ruby on Rails application that is used by national radio stations (e.g., QMusic, JoeFM, and Willy). Work on removing technical debt and increasing test coverage. • Designed an API to be consumed by native mobile apps. • Developed a radio player widget to be embedded in multiple frontends. Medior Developer OMAKASE ⋅ [ 2015 – 2019 ] • Architected a community platform with social features like a web feed, discussion board, live chat, and job board • Set up CI/CD pipelines and monitoring. Managed infrastructure and tuned a bare metal server configuration to maximize performance. • Managed a team consisting of designers, frontend- and backend developers. Junior Developer MULTIMEDIUM ⋅ [ 2012 – 2015 ] • Started with no professional background or any relevant training and quickly took the position as the lead front-end developer. • Built an asset management tool for a large supplier of dentistry products. • Launched audience engagement games on eCommerce websites with more than 10,000 active users. • Manually crafted HTML newsletters for a large media production house --- SKILLS --- Ruby On Rails, Hotwire, JavaScript, UNIX, HTML, CSS, MySQL, PostgreSQL, RubyGems, Docker, Neovim, Nginx, AWS, Photoshop, Figma, Sketch and more --- CLIENT LIST --- Perrigo, European Commission, LiveNation, Samsonite, Pearl Vision, MTV, DPG Media, Bpost, Studio 100, Jaga, KIA --- PERSONAL --- • Born in 1988 • Living in Belgium • MBTI-INTJ personality • Father of a boy and a girl • Hobbies: making, building, brewing, • squash, cuisine, road trips --- EDUCATION --- Master of Education (M.Ed.) UNIVERSITY OF ANTWERP [ 2011 – 2012 ] Master of Science (M.Sc.), Biology: Ecology & Environment UNIVERSITY OF ANTWERP [ 2009 – 2011 ] Bachelor, Biology UNIVERSITY OF ANTWERP [ 2006 – 2009 ] High School KLEIN SEMINARIE HOOGSTRATEN [ 2000 – 2006 ]

With 9 years of engineering excellence across diverse domains, I've mastered the art of transforming complex challenges into elegant technological solutions. As the creator and maintainer of the Solid Queue Monitor gem(https://rubygems.org/gems/solidqueuemonitor) —a zero-dependency monitoring solution for Rails background jobs—I've demonstrated my commitment to improving developer tooling in the Ruby ecosystem. In my current role as a Staff Engineer at Torch.io, a coaching platform trusted by industry giants like Stripe, LinkedIn, Airbnb, and TripAdvisor, I've revolutionized support systems by implementing OpenAI's GPT-3.5 for email automation, reducing manual intervention by 48%. I've also leveraged AWS Bedrock with Claude 3.7 to generate organizational insights reports, improving decision-making efficiency by 40%. My technical versatility spans the full spectrum of development—from crafting robust backends with Ruby, Go, and Python to building responsive frontends with React, Angular, and TypeScript. I've engineered large-scale data applications handling 5+ million active users and orchestrated seamless migrations of 4.5 million records while maintaining system integrity. Throughout my career, I've delivered impactful solutions across multiple domains—enhancing FinTech security protocols, optimizing CMS performance, and elevating coaching platforms. This domain versatility, combined with my technical depth and AI integration expertise, allows me to bring a unique perspective to every project and consistently deliver transformative results.

Rails architect with UX fluency, blending 20+ years of technical mastery with design thinking. Specializing in microservices, AI, and data platforms, I build developer-first solutions that scale.

I am an experienced senior engineer with more than 8 years of industry exposure. I love to help entrepreneurs build and launch their startups and projects with full technical ownership. I have helped multiple aspiring founders by building their products: - https://sponsorless.com - https://devtree.app - https://getrecognise.com I primarily work with: - Ruby on Rails - Hotwire - Postgres - TailwindCSS - Sidekiq - Redis - Docker - and much more I also have experience working on several third party API's like Shopify, Stripe, DNsimple and AWS.

I am Kirui Elias, a Rails Software Engineer with expertise in Ruby on Rails, Laravel, Python, Hotwire, React, and Tailwind CSS. I have a deep understanding of the Rails framework and a strong command of the Ruby language. With vast experience, I have built software products following best practices like DRY, CI/CD, and testing. I have also developed custom modules, including Stripe & MPESA payment integration & other API integrations. I am skilled in deploying applications using AWS, Digital Ocean, Heroku, Netlify, Vercel, and others. I am seeking a role where I can leverage my skills to bring value and grow further. Available for full-time positions.

I’m a product-minded developer who builds with the business’s needs front of mind. Ruby on Rails is my tool of choice because it’s the fastest way to turn ideas into impact. Its opinionated structure enables consistent delivery and makes it easier to scale teams without reinventing the wheel. Over the past decade, I’ve led and contributed to projects that not only ship but drive significant business impact In one internal platform modernization project, leadership projected needing 16 full time employees after the rebuild. Four years later, the same team of four was still using the software productively saving the company 12 full time employees. I also look beyond the technical tasks to spot leveraged opportunities. On a recent project, I identified a low-priority feature that, if built more robustly upfront, could unlock internal productivity. That decision now saves every employee 30 minutes a day, which results in thousands of hours a year saved. I thrive when building internal platforms, business efficiency, and moving fast to get the business impact as quickly as possible.

With 15+ years in software development, I specialize in crafting scalable, high-performance web applications using Ruby on Rails, Hotwire, and Kamal. My expertise extends beyond development. I connect developers, leadership, DevOps, and security, ensuring seamless collaboration, robust architectures, and optimized performance. Over the years, I’ve worn many hats, from Tech Lead Software Engineer and Senior Staff Engineer to Management Consultant and Lecturer at HTW Berlin. These roles have shaped my ability to build strong engineering teams, mentor developers, and drive innovation while maintaining a hands-on approach to solving technical challenges. 💡 What sets me apart? Full-Stack Expertise: Rails, Hotwire (Turbo & Stimulus), PostgreSQL, and Elasticsearch Cloud & DevOps: Kamal, Docker, Terraform, AWS, and zero-downtime deployments Performance & Security: Scaling applications, optimizing databases, and securing web apps Leadership & Mentorship: Guiding engineering teams and fostering a culture of innovation I thrive on solving complex challenges, optimizing workflows, and building future-proof applications. Whether leading teams, consulting on architecture, or automating cloud deployments, I’m driven by a passion for efficiency, innovation, and delivering high-quality software solutions. Let’s connect and build something exceptional! 🚀

Seasoned Rails consultant with 8+ years of experience. From MVPs to products with millions of users. Self-driven and easy to manage. I can provide up to 6 hours of overlap with the US timezone and full overlap with EU/UK time zones. Remote: Global, OnSite: India/Middle East/Asia. Some Interesting Complex Problems Solved AI integrations using voice models, openAI, and random forests. Video/audio freeze detection: Used openCV to detect if a video is in a frozen state with more than 99% accuracy CoBrowsing: Created CoBrowsing feature for a customer service app that allows to take control of a customer's browser without using any plugins except this JS CoBrowsing widget code. Server management platform: An internal dashboard for a client that allows users to control thousands of servers and field devices scattered across the globe. It allows the users to execute scripts on those servers, configure, provision, web-based SSH, etc. Common Freelance Gigs Performance optimizations of Rails, PostgreSQL, and Sidekiq: Helped multiple clients to scale Rails Upgrades Legacy modernization: Helping legacy Rails applications to modernize the stack, including the front end. For example, Recently, I helped convert CoffeeScript/AngularJS 1.0 to JS/Vue. Third-party integrations. Skills: Ruby on Rails PostgreSQL React Stimulus TypeScript JavaScript GraphQL Server - Ruby GraphQL Client - Apollo CI/CD (CircleCI, Jenkins) Heroku

IT professional (since 2011), specializing as a backend-heavy full-stack engineer with a focus on Ruby / Ruby on Rails (since 2014). Strong in database design and SQL optimization (Oracle, PostgreSQL). Adept in shell scripting and testing (RSpec, Cypress). Experience includes working in both large international corporations with a multicultural environment and small local startups. Experienced in leading teams and mentoring trainees (since 2018). Successfully delivered over 25 projects across diverse sectors, including telecom, GIS, AI/ML, real estate, and EdTech. Holds a B.Sc. in Computer Science and an M.Sc. in Applied Informatics.

Senior software engineer with over 10 years of experience as a remote freelancer. My educational background includes an MSc 2:1 in computer science and applied mathematics engineering from ENSEEIHT (Toulouse, France) in 2009. I then worked for 2 years as a frontend developer at a startup in London and transitioned to backend work in 2013. Specializing in web application development, I have undertaken projects for companies such as Carrefour, L'Oréal, Cocolis, Epicery, and Alerti. My work has encompassed backend development, data engineering, code and database performance improvement, e-commerce platform customization and logistics, payment system integration, API creation, crawlers, technical documentation, and testing. Passionate about data manipulation and rendering them to users and stakeholders in a more meaningful way, I am currently expanding my skills in AI/ML and neural networks through CNRS fidle formation to explore how I could apply and offer these services to my clients. Recent milestones and accomplishments include: Migrating the payment system from Adyen to Stripe for Epicery Migrating the frontend from Vue to Hotwire for Epicery Developing a geolocalized matching algorithm between carriers and packages for Cocolis Fields of expertise: E-commerce solutions with Solidus/Spree open-source framework Data processing and visualization with Business Intelligence tools for reporting Integration of payment system providers Integration of third-party APIs Database design and performance optimization Frontend performance optimization Crawling and scraping Technical audits Testing, documentation, CI/CD tools Experience with the following tools: Languages: Ruby, Typescript, JavaScript, Node.js, Ruby on Rails Platforms: AWS, Google Cloud Platform, Render, Heroku Frontend: React, Vue.js, Hotwire, Angular, HTML/CSS, Alpine.js, HTMX, Astro Payment providers: Stripe, Mangopay, Adyen, PayPal Data viz: Amazon QuickSight, Superset, Tableau Backend tools: Solidus open-source e-commerce solution, New Relic, Elasticsearch, PostgreSQL, Amazon S3, etc. CI/CD Tools: GitHub CI, CircleCI Fluent in French, English, Spanish.