Custom platforms, SaaS products, and AI workflows built on fixed-scope contracts with weekly demos. For teams of 10-200 who've been burned before.
Aktualisiert am 23.03.2026
Profil
Freiberufler / Selbstständiger
Remote-Arbeit
Verfügbar ab: 23.03.2026
Verfügbar zu: 100%
davon vor Ort: 10%
Ruby on Rails
Node.js
DevOps
JavaScript
Ruby
React
Flutter
Linux
Web Application
Software as a Service
Software
Vue.js
Laravel
Elixir

Einsatzorte

Einsatzorte

Berlin (+500km)
Deutschland, Schweiz, Österreich
möglich

Projekte

Projekte

4 years 10 months
2021-06 - now

Engineered and maintained core features of the uTest platform

Full Stack Developer
Full Stack Developer
  • Engineered and maintained core features of the uTest platform the world's largest crowdsourced testing community serving 1.5M+ registered testers across 200+ countries for enterprise clients including Google, Microsoft, Amazon, Ford, and Disney, contributing to $200M+ ARR.
  • Ledmultiple Ruby and Rails major version upgrades across the platform, ensuring zero-downtime migrations, dependency compatibility, and security compliance.
  • Drove the AngularJS to Angular16 frontend migration, modernizing the legacy codebase, improving devel oper productivity, and reducing technical debt across critical user-facing work ows.
  • Architected a platform-wide search migration to Elasticsearch with RabbitMQ-backed data syncing, im proving search relevance and query performance for millions of tester pro les and test cycles.
  • Collaborated with cross-functional teams (Product, QA, DevOps) in a distributed, async- rst environment to ship features that improved tester-client matching, contributing to Applause's NPS score of 69 (vs. industry average of 40).
Applause (uTest Platform), Berlin, Germany
1 year 4 months
2020-02 - 2021-05

Contributed to the Opportunity Generation and Monetization team

Senior Software Engineer
Senior Software Engineer
  • Contributed to the Opportunity Generation and Monetization team, delivering customer-oriented features that improved insurance product recommendations and conversion ows.
  • Built and maintained Kubernetes-based dynamic staging environments on the Architecture & Maintenance team, accelerating developer velocity and enabling parallel feature testing across microservices.
  • Shipped frontend features in the Ember.js application, collaborating across backend (Ruby on Rails) and frontend teams to deliver seamless user experiences in Germany's leading digital insurance platform.
CLARK, Frankfurt am Main, Germany
10 months
2019-04 - 2020-01

Maintained andenhanced the customer-facing platform

Web Developer
Web Developer
  • Maintained andenhanced the customer-facing platform of one of Thailand's largest MVNO telecom providers, serving millions of subscribers for subscription management, account administration, and support work ows.
  • Built RESTful APIs powering companion mobile applications and developed features used by customer service and admin teams to manage accounts at scale.
  • Participated in cross-functional feature planning, implementing solutions following TDD best practices with RSpec and collaborating in an agile, distributed team environment.
OOZOU, Bangkok, Thailand
1 year 8 months
2017-11 - 2019-06

Architected the core system

Senior Software Engineer
Senior Software Engineer
  • Architected the core system from scratch for a white-label Online Travel Agency (OTA) SaaS platform, designing the domain model, service layer, and API architecture.
  • Integrated the Sabre GDS API for air ticket booking and implemented multiple local payment gateway integrations, enabling end-to-end travel booking and payment work ows.
  • Led and mentored a development team as technical lead and DevOps engineer, establishing code standards, distributing tasks, and conducting code reviews to ensure quality across releases.
Haltrip.com, Dhaka, Bangladesh
11 months
2017-11 - 2018-09

Developed 3PL e-commerce fulfillment automation software

Lead Developer
Lead Developer
  • Developed 3PL e-commerce fulfillment automation software, integrating with Shopify, Amazon, WooCommerce, postal/courier services (Australia Post, cParcel), and accounting platforms (Xero).
  • Iterated rapidly based on direct user feedback, adapting the warehouse operations system to match customer work ows and growing the automated test suite to achieve strong coverage.
Keep Space Pty Ltd, Remote (Australia)
1 year 1 month
2016-10 - 2017-10

Delivered a real-time Live Chat system

Senior Software Engineer
Senior Software Engineer
  • Delivered a real-time Live Chat system built with Ruby on Rails, ActionCable, WebSockets, and React, along with organizer and support ticket management components.
  • Led development of the payment system integration using Rails, React, and Redux, working end-to-end from requirements analysis through deployment. 
  • Mentored junior engineers, conducted pull request reviews, and contributed to team-wide code quality standards and RSpec test coverage improvements.
WellTravel AG, Dhaka, Bangladesh
3 years 6 months
2013-02 - 2016-07

Built a SaaS B2B e-commerce application

Web Developer
Web Developer
  • Built a SaaS B2B e-commerce application for the US food industry and an LMS for a technical training centre in New York. 
  • Trained colleagues in PHP and WordPress development. 
  • Collaborated with UNESCO Dhaka and BNFE on technical projects.
Xenex Web Solutions, Dhaka, Bangladesh
2 years 5 months
2010-09 - 2013-01

Developed custom WordPress themes and plugins

Freelance WordPress Developer
Freelance WordPress Developer
  • Developed custom WordPress themes and plugins, achieving 3,600+ downloads on the WordPress Plugin Repository.
  • Scored top 90th percentile on WordPress assessments.
Self-Employed / oDesk, Remote

Aus- und Weiterbildung

Aus- und Weiterbildung

ISC, General Science Govt. Science College, Dhaka, Bangladesh

Kompetenzen

Kompetenzen

Top-Skills

Ruby on Rails Node.js DevOps JavaScript Ruby React Flutter Linux Web Application Software as a Service Software Vue.js Laravel Elixir

Produkte / Standards / Erfahrungen / Methoden

Professional Summary

Senior Full-Stack Software Engineer with 14+ years of experience building and scaling web applications in Ruby on Rails, React, Angular, and TypeScript. Currently engineering the world's largest crowdsourced testing platform at Applause serving 1.5M+ testers across 200+ countries for Fortune 500 clients including Google, Microsoft, and Amazon. Led multiple major Rails version upgrades, architected an Elasticsearch migration with RabbitMQ-backed syncing, and drove a legacy AngularJS-to-Angular16 modernization. Published author (Programming with Ruby). Proven track record of mentoring engineers and delivering high-reliability systems in distributed, remote- rst teams.


Technical Skills

  • Frameworks: Ruby on Rails (58), React, Angular (AngularJS16), Ember.js, Hotwire/Turbo/Stimulus, Laravel, Symfony
  • Cloud & DevOps: Amazon Web Services (AWS), Docker, Kubernetes (k8s), CI/CD, GitHub Actions, Dynamic Staging Environments
  • Messaging & Search: RabbitMQ, Sidekiq, Elasticsearch
  • Testing: RSpec, TDD/BDD, Capybara, Jest
  • Tools & Practices: Git, GitHub, REST APIs, GraphQL, WebSockets, ActionCable, Agile/Scrum, Code Review, System Design, Microservices Architecture

Programmiersprachen

Ruby
Experte
JavaScript
Experte
PHP
Fortgeschritten
TypeScript
HTML5
CSS3
SQL
Elixir

Datenbanken

PostgreSQL
Experte
MySQL
Experte
Redis
Elasticsearch

Einsatzorte

Einsatzorte

Berlin (+500km)
Deutschland, Schweiz, Österreich
möglich

Projekte

Projekte

4 years 10 months
2021-06 - now

Engineered and maintained core features of the uTest platform

Full Stack Developer
Full Stack Developer
  • Engineered and maintained core features of the uTest platform the world's largest crowdsourced testing community serving 1.5M+ registered testers across 200+ countries for enterprise clients including Google, Microsoft, Amazon, Ford, and Disney, contributing to $200M+ ARR.
  • Ledmultiple Ruby and Rails major version upgrades across the platform, ensuring zero-downtime migrations, dependency compatibility, and security compliance.
  • Drove the AngularJS to Angular16 frontend migration, modernizing the legacy codebase, improving devel oper productivity, and reducing technical debt across critical user-facing work ows.
  • Architected a platform-wide search migration to Elasticsearch with RabbitMQ-backed data syncing, im proving search relevance and query performance for millions of tester pro les and test cycles.
  • Collaborated with cross-functional teams (Product, QA, DevOps) in a distributed, async- rst environment to ship features that improved tester-client matching, contributing to Applause's NPS score of 69 (vs. industry average of 40).
Applause (uTest Platform), Berlin, Germany
1 year 4 months
2020-02 - 2021-05

Contributed to the Opportunity Generation and Monetization team

Senior Software Engineer
Senior Software Engineer
  • Contributed to the Opportunity Generation and Monetization team, delivering customer-oriented features that improved insurance product recommendations and conversion ows.
  • Built and maintained Kubernetes-based dynamic staging environments on the Architecture & Maintenance team, accelerating developer velocity and enabling parallel feature testing across microservices.
  • Shipped frontend features in the Ember.js application, collaborating across backend (Ruby on Rails) and frontend teams to deliver seamless user experiences in Germany's leading digital insurance platform.
CLARK, Frankfurt am Main, Germany
10 months
2019-04 - 2020-01

Maintained andenhanced the customer-facing platform

Web Developer
Web Developer
  • Maintained andenhanced the customer-facing platform of one of Thailand's largest MVNO telecom providers, serving millions of subscribers for subscription management, account administration, and support work ows.
  • Built RESTful APIs powering companion mobile applications and developed features used by customer service and admin teams to manage accounts at scale.
  • Participated in cross-functional feature planning, implementing solutions following TDD best practices with RSpec and collaborating in an agile, distributed team environment.
OOZOU, Bangkok, Thailand
1 year 8 months
2017-11 - 2019-06

Architected the core system

Senior Software Engineer
Senior Software Engineer
  • Architected the core system from scratch for a white-label Online Travel Agency (OTA) SaaS platform, designing the domain model, service layer, and API architecture.
  • Integrated the Sabre GDS API for air ticket booking and implemented multiple local payment gateway integrations, enabling end-to-end travel booking and payment work ows.
  • Led and mentored a development team as technical lead and DevOps engineer, establishing code standards, distributing tasks, and conducting code reviews to ensure quality across releases.
Haltrip.com, Dhaka, Bangladesh
11 months
2017-11 - 2018-09

Developed 3PL e-commerce fulfillment automation software

Lead Developer
Lead Developer
  • Developed 3PL e-commerce fulfillment automation software, integrating with Shopify, Amazon, WooCommerce, postal/courier services (Australia Post, cParcel), and accounting platforms (Xero).
  • Iterated rapidly based on direct user feedback, adapting the warehouse operations system to match customer work ows and growing the automated test suite to achieve strong coverage.
Keep Space Pty Ltd, Remote (Australia)
1 year 1 month
2016-10 - 2017-10

Delivered a real-time Live Chat system

Senior Software Engineer
Senior Software Engineer
  • Delivered a real-time Live Chat system built with Ruby on Rails, ActionCable, WebSockets, and React, along with organizer and support ticket management components.
  • Led development of the payment system integration using Rails, React, and Redux, working end-to-end from requirements analysis through deployment. 
  • Mentored junior engineers, conducted pull request reviews, and contributed to team-wide code quality standards and RSpec test coverage improvements.
WellTravel AG, Dhaka, Bangladesh
3 years 6 months
2013-02 - 2016-07

Built a SaaS B2B e-commerce application

Web Developer
Web Developer
  • Built a SaaS B2B e-commerce application for the US food industry and an LMS for a technical training centre in New York. 
  • Trained colleagues in PHP and WordPress development. 
  • Collaborated with UNESCO Dhaka and BNFE on technical projects.
Xenex Web Solutions, Dhaka, Bangladesh
2 years 5 months
2010-09 - 2013-01

Developed custom WordPress themes and plugins

Freelance WordPress Developer
Freelance WordPress Developer
  • Developed custom WordPress themes and plugins, achieving 3,600+ downloads on the WordPress Plugin Repository.
  • Scored top 90th percentile on WordPress assessments.
Self-Employed / oDesk, Remote

Aus- und Weiterbildung

Aus- und Weiterbildung

ISC, General Science Govt. Science College, Dhaka, Bangladesh

Kompetenzen

Kompetenzen

Top-Skills

Ruby on Rails Node.js DevOps JavaScript Ruby React Flutter Linux Web Application Software as a Service Software Vue.js Laravel Elixir

Produkte / Standards / Erfahrungen / Methoden

Professional Summary

Senior Full-Stack Software Engineer with 14+ years of experience building and scaling web applications in Ruby on Rails, React, Angular, and TypeScript. Currently engineering the world's largest crowdsourced testing platform at Applause serving 1.5M+ testers across 200+ countries for Fortune 500 clients including Google, Microsoft, and Amazon. Led multiple major Rails version upgrades, architected an Elasticsearch migration with RabbitMQ-backed syncing, and drove a legacy AngularJS-to-Angular16 modernization. Published author (Programming with Ruby). Proven track record of mentoring engineers and delivering high-reliability systems in distributed, remote- rst teams.


Technical Skills

  • Frameworks: Ruby on Rails (58), React, Angular (AngularJS16), Ember.js, Hotwire/Turbo/Stimulus, Laravel, Symfony
  • Cloud & DevOps: Amazon Web Services (AWS), Docker, Kubernetes (k8s), CI/CD, GitHub Actions, Dynamic Staging Environments
  • Messaging & Search: RabbitMQ, Sidekiq, Elasticsearch
  • Testing: RSpec, TDD/BDD, Capybara, Jest
  • Tools & Practices: Git, GitHub, REST APIs, GraphQL, WebSockets, ActionCable, Agile/Scrum, Code Review, System Design, Microservices Architecture

Programmiersprachen

Ruby
Experte
JavaScript
Experte
PHP
Fortgeschritten
TypeScript
HTML5
CSS3
SQL
Elixir

Datenbanken

PostgreSQL
Experte
MySQL
Experte
Redis
Elasticsearch

Vertrauen Sie auf Randstad

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Im Bereich Arbeitnehmerüberlassung / Personalvermittlung

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