Available to hire
Hi, I’m Marcin A. Zajkowski, a dedicated Front-End Developer with extensive experience in building websites, e-learning modules, interactive sales tools, and multimedia presentations across various industries including publishing, travel, and medical safety training. I enjoy creating user-friendly and scalable digital solutions while mentoring fellow developers and leading teams.
With a strong background in modern front-end frameworks and tools, I continuously strive to improve code quality and streamline project delivery. I am passionate about sharing my knowledge through training sessions and actively participating in hiring and performance reviews to build strong development teams.
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Work Experience
Web Application Developer at New Media Pilot
January 1, 2025 - June 10, 2024Developed websites for clients in publishing, travel, and fitness industries; built e-learning safety modules for medical safety training; created interactive sales tools for a medical manufacturer; produced dynamic multimedia presentations and promotional puzzle games; refactored and converted custom code and multimedia formats; produced diverse Google Ads campaigns for banking sector clients; advised on website development, integration, and digital strategy.
Technologist at Critical Mass
January 1, 2020 - December 31, 2024Oversaw full site production lifecycle—from concept to deployment—for high-profile digital campaigns; mentored developers, enhancing engagement and code quality through feedback and PR reviews; built and integrated internal tools and processes to streamline delivery; led seasonal marketing initiatives; facilitated client-facing technical reviews and collaborated on quality alignment; created documentation and system diagrams for scalable front-end solutions; ran training sessions on modern front-end practices; participated in hiring, interviews, and annual performance reviews; maintained compliance with GDPR and security training.
Team Lead at E-Suite
January 1, 2015 - December 31, 2020Created prototypes and functional demos in collaboration with UX designers; participated in daily stand-ups and stakeholder meetings; maintained AWS pipeline (EC2, ELB, RDS) and VPN access; investigated and resolved bugs; contributed to team growth through hiring and onboarding.
Web Developer at Sapient Nitro
January 1, 2013 - December 31, 2014Created banner animations for the Google Ads platform; migrated legacy NoSQL application data to a modern platform; updated content across multiple accounts and CMS platforms; participated in client team-building initiatives.
Game Developer at Realtime Edge Software
January 1, 2012 - December 31, 2013Optimized casino games for performance; updated graphics and created new game themes; rebuilt game mechanics using modular animation techniques; refactored game logic for scalability and readability.
Web Developer at Twist Image
January 1, 2010 - December 31, 2011Built a mortgage calculator tool; participated in the creation of a social sharing microsite; attended planning sessions and strategy meetings.
Web Developer at Publicis Inc
January 1, 2007 - December 31, 2010Developed ad campaigns for mobile product launches; built microsites for promotional marketing initiatives; established a Flash microsite production workflow, improving team productivity.
E-Learning Developer at Engage Learning Systems
December 31, 2000 - December 30, 2005• Collaborated on programming e-learning modules and client consultations • Built learning modules using Adobe Flash • Developed graphics, designs, and animations • Created prototypes, comps and participated in stand-ups • Integrated result APIs with external client systems to record user results
Senior Page at Toronto Public Library
January 1, 1996 - December 31, 2000Circulated library materials using CLI-based systems; maintained collection integrity and ensured item findability; repaired damaged or defective items; provided customer service; assisted in reorganizing neighboring library branch.
Web Application Developer at New Media Pilot
January 1, 2001 - PresentDeveloped websites for clients in publishing, travel, and fitness industries. Built e-learning safety modules for medical safety training. Created interactive sales tools for a medical manufacturer. Produced dynamic multimedia presentations. Designed and developed promotional puzzle games. Refactored and converted custom code and multimedia formats. Produced diverse Google Ads campaigns for banking sector clients. Advised on website development, integration, and digital strategy.
Technologist at Critical Mass
January 1, 2024 - July 10, 2025Oversaw full production lifecycle of digital campaigns from concept to deployment. Mentored developers, enhancing engagement and code quality through feedback and PR reviews. Built and integrated internal tools and processes to streamline delivery. Helped produce seasonal marketing initiatives including email and banner campaigns. Participated in client-facing technical reviews and collaborated with design, QA, and stakeholders. Created documentation and system diagrams for scalable front-end solutions. Ran training sessions on modern front-end practices and code standards. Participated in hiring, interviews, and performance reviews. Estimated project timelines and reviewed pull requests for best practices. Maintained compliance with GDPR and security training.
Team Lead at E-Suite
January 1, 2020 - July 10, 2025Created prototypes and functional demos in collaboration with UX designers. Participated in daily stand-ups and stakeholder meetings. Maintained AWS pipeline (EC2, ELB, RDS) and VPN access. Investigated and resolved bugs reported by QA and end users. Contributed to team growth through hiring and onboarding. Maintained VPN access for the team.
Web Developer at Sapient Nitro
December 31, 2014 - July 10, 2025Created banner animations for the Google Ads platform. Migrated legacy NoSQL application data to a modern platform. Updated content across multiple accounts and CMS platforms. Participated in client team-building initiatives.
Game Developer at Realtime Edge Software
December 31, 2013 - July 10, 2025Optimized a series of games for performance. Updated graphics and created new themes for various games. Rebuilt game mechanics to use modern modular animation techniques. Refactored game logic for scalability and readability.
Web Developer at Twist Image
December 31, 2011 - July 10, 2025Built a mortgage calculator tool. Participated in the creation of a social sharing microsite. Attended planning sessions and strategy meetings.
Web Developer at Publicis Inc
December 31, 2010 - July 10, 2025Developed ad campaigns for mobile product launches. Built microsites for promotional marketing initiatives. Established a Flash microsite production workflow, improving team productivity.
E-Learning Developer at Engage Learning Systems
December 31, 2005 - July 10, 2025Collaborated on programming e-learning modules and client consultations. Built learning modules for managers and employees using Adobe Flash. Developed graphics, designs and animations. Created prototypes and comps and participated in stand-ups. Integrated result APIs with external client systems to record user results.
Senior Page at Toronto Public Library
December 31, 2000 - July 10, 2025Circulated library materials using CLI-based systems. Maintained collection integrity and ensured item findability. Repaired damaged or defective items in the collection. Provided customer service at help desk, checkout, and on the floor. Assisted in reorganizing a neighboring library branch.
Web Application Developer at New Media Pilot
January 1, 2001 - PresentDeveloped websites for clients in publishing, travel, and fitness industries; built e-learning safety modules for medical safety training; created interactive sales tools for a medical manufacturer; produced dynamic multimedia presentations; designed and developed promotional puzzle games; refactored and converted custom code and multimedia formats; assembled diverse Google Ads campaigns for banking sector clients; advised on website development, integration, and digital strategy.
Technologist at Critical Mass
January 1, 2024 - July 30, 2025Oversaw full production lifecycle from concept to deployment for various digital campaigns; mentored developers to enhance engagement and code quality through feedback and PR reviews; built and integrated internal tools and processes; helped produce seasonal marketing initiatives including email and banner campaigns; participated in client-facing technical reviews; collaborated with design, QA, and stakeholders; created documentation and system diagrams for scalable front-end solutions; ran training sessions on modern front-end practices; participated in hiring, interviews, and performance reviews; estimated project timelines; maintained GDPR compliance and security training.
Team Lead at E-Suite
January 1, 2020 - July 30, 2025Created prototypes and functional demos with UX designers; participated in daily stand-ups and stakeholder meetings; maintained AWS pipeline including EC2, ELB, RDS and VPN access; investigated and resolved bugs reported by QA and end users; contributed to team growth through hiring and onboarding; maintained VPN access for the team.
Web Developer at Sapient Nitro
December 31, 2014 - July 30, 2025Created banner animations for Google Ads platform; migrated legacy NoSQL application data to modern platform; updated content across multiple accounts and CMS platforms; participated in client team-building initiatives.
Game Developer at Realtime Edge Software
December 31, 2013 - July 30, 2025Optimized a series of games for performance; updated graphics and created new themes; rebuilt game mechanics using modern modular animation techniques; refactored game logic for scalability and readability.
Web Developer at Twist Image
December 31, 2011 - July 30, 2025Built mortgage calculator tool; participated in creation of social sharing microsite; attended planning and strategy meetings.
Web Developer at Publicis Inc
December 31, 2010 - July 30, 2025Developed ad campaigns for mobile product launches; built microsites for promotional marketing; established Flash microsite production workflow improving team productivity.
E-Learning Developer at Engage Learning Systems
December 31, 2005 - July 30, 2025Collaborated on programming e-learning modules and client consultations; built learning modules for managers and employees using Adobe Flash; developed graphics, designs, and animations; created prototypes and comps; integrated result APIs with external client systems to record user results.
Senior Page at Toronto Public Library
December 31, 2000 - July 30, 2025Circulated library materials using CLI-based systems; maintained collection integrity; repaired damaged or defective items; provided customer service at help desk, checkout, and on the floor; assisted in reorganizing a neighboring library branch.
Education
Diploma at Cardinal Carter Academy for the Arts
January 1, 1998 - December 31, 2003Diploma at Cardinal Carter Academy for the Arts
January 1, 1998 - December 31, 2003Diploma at Cardinal Carter academy for the Arts
January 1, 1998 - December 31, 2003Qualifications
Mastering React (Coding with Mosh)
January 1, 2015 - December 31, 2015Mastering Angular 2.0 (Coding with Mosh)
January 1, 2015 - December 31, 2015Mastering Git (Coding with Mosh)
January 1, 2015 - December 31, 2015Mastering Redux (Coding with Mosh)
January 1, 2015 - December 31, 2015Omnicom OWASP, GDPR, Accessibility Training
January 1, 2018 - December 31, 2018Swift 5 Qualification Certification
January 1, 2018 - December 31, 2018Mastering React (Coding with Mosh)
January 1, 2020 - December 31, 2020Mastering Angular 2.0 (Coding with Mosh)
January 1, 2020 - December 31, 2020Mastering Git (Coding with Mosh)
January 1, 2020 - December 31, 2020Mastering Redux (Coding with Mosh)
January 1, 2020 - December 31, 2020Omnicom OWASP , GDPR, Accessibility Training
January 1, 2022 - December 31, 2022Swift 5 Qualification Certification
January 1, 2019 - December 31, 2019Mastering React (Coding with Mosh)
January 1, 0000 - December 31, 0000Mastering Angular 2.0 (Coding with Mosh)
January 1, 0000 - December 31, 0000Mastering Git (Coding with Mosh)
January 1, 0000 - December 31, 0000Mastering Redux (Coding with Mosh)
January 1, 0000 - December 31, 0000Omnicom OWASP , GDPR, Accessibility Training
January 1, 0000 - December 31, 0000Swift 5 Qualification Certification
January 1, 0000 - December 31, 0000Industry Experience
Software & Internet, Media & Entertainment, Healthcare, Travel & Hospitality, Financial Services, Education, Gaming, Non-Profit Organization, Professional Services
Skills
Experience Level
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
Intermediate
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