Mariusz Droździel
Verified Expert in Engineering
Ruby on Rails Developer
Mariusz is a technology enthusiast, passionate developer, and manager with more than 20 years of experience in almost every IT segment. For the last 12 years, he has acted as an active Ruby on Rails developer, creating several applications mainly for the eCommerce, AdTech, and telco sectors. Mariusz combines solid technical skills in systems design and maintenance, networks, and software development, with excellent project and team management competencies.
Portfolio
Experience
Availability
Preferred Environment
MacOS, Vim Text Editor, Asana, Slack, Trello, GitHub, GitLab
The most amazing...
...app I’ve designed and developed was an in-house VoIP solution based on FreeSwitch and built from scratch in Ruby on Rails.
Work Experience
CTO and Lead Developer
Admads
- Built a custom, comprehensive SIP VoIP platform in Ruby on Rails using FreeSWITCH PBX. The app was used by 100 active phone consultants. I also created advanced AdTech-related apps with Ruby on Rails 6.1 and PostgreSQL, serving up to 50,000 dynamic RPS.
- Tested the Ruby on Rails apps using RSpec and used a custom zero-downtime deployment setup based on modern CI/CD solutions, such as CircleCI and GitHub Actions, enabling the delivery of a robust and steady flow of stable, new features.
- Led all IT operations and actively participated in most development and infrastructure tasks, performing various API integrations with external platforms.
- Integrated the company as the first hired employee overlooking all technical operations. The company grew up to over 150 employees in seven years.
Trainer | Linux Specialist | Lead Developer
ALX
- Created many stationary training courses, such as Basic and Advanced Linux Administration, Programming in Tcl/Tk, PostgreSQL-based introductory SQL, and others related to Ruby on Rails.
- Managed a Linux-based infrastructure for clients. Developed the company's internal CRM/CMS app based on Python and Django, moved the app onto CI/CD pipeline, and created an extensive test suite.
- Facilitated training courses on a less continuous basis. Prepared a custom internal training for one of the biggest Polish insurance companies.
Chief Network and System Administrator
Teleaudio | Polsat TV
- Planned and maintained the LAN network with 200+ workstations and the WAN network of Polsat TV with 20+ routers. Handled system administration of 30+ UNIX-based servers using Linux, OpenBSD, FreeBSD, SCO OpenServer, and Solaris.
- Maintained databases, mail servers, the LDAP protocol, the web, backup systems, and network and system monitoring solutions.
- Developed an internal application to solve issues with scheduling shifts for over 1500 employees. The application was built in Ruby on Rails 2 and 3, backed by a Microsoft SQL database.
- Created a web interface to manage the DHCP configuration for over 1000 devices using Ruby on Rails 3 and PostgreSQL.
Experience
SIP VoIP platform based on FreeSwitch
Skills
Languages
Ruby, CSS, HTML, SQL, Python, JavaScript, CoffeeScript, Go, Elixir, Clojure
Frameworks
Ruby on Rails (RoR), Django, Hanami, Tailwind CSS, Stimulus
Tools
Vim Text Editor, Asana, Slack, Trello, GitHub, GitLab, NGINX, Git, RSpec, RabbitMQ, Varnish, FreeSWITCH, Amazon Simple Email Service (SES), Spree
Paradigms
Unit Testing, Test-driven Development (TDD), Microservices, Event Sourcing
Platforms
MacOS, Linux, Amazon Web Services (AWS), Docker, Heroku
Storage
PostgreSQL, Memcached, Redis, MySQL, Amazon S3 (AWS S3), Elasticsearch, NoSQL
Other
APIs, Technical Hiring, Source Code Review, Code Review, Interviewing, Task Analysis, PBX, VoIP, Programming, Computer Science, Networks, Electronics, Computer Networking, BGP, Cisco, SOAP, Spree Commerce
Libraries/APIs
Stripe API
Education
Bachelor of Science Degree in Computer Networking
Warsaw University of Technology - Warsaw, Poland
Bachelor of Science Degree in Computer Networking
Technical University of Denmark - Copenhagen, Denmark
Certifications
LPIC-2
Linux Professional Institute
LPIC-1
Linux Professional Institute