Grzegorz Marzencki
Verified Expert in Engineering
JavaScript Developer
Grzegorz has experience leading teams and working as a CTO. He is an expert JavaScript developer and trainer with expertise in front-end architecture design and team leadership. He has delivered projects for startups (including an MVP that won business funding) and large tech companies like Microsoft, MongoDB, and Two Sigma. Grzegorz's strengths are team leadership, building scalable architectures, and delivering the highest quality code.
Portfolio
Experience
Availability
Preferred Environment
WebStorm
The most amazing...
...product I've delivered was an MVP for a startup that got the company funding. I was later hired to build the development team from the ground up.
Work Experience
JavaScript Developer and Architect
Freelance
- Assisted startups and FAANG companies as an architect, tech lead, and developer.
- Designed front-end architecture and oversaw the entire delivery process (from idea to solution).
- Led teams of designers and developers and worked closely with project owners.
JavaScript Trainer
jstrainings.com
- Delivered around 1,000 hours of technical training about JavaScript and web technologies.
- Created training for people from companies such as (but not limited to): Orange, Ericsson, Nordea, and Comarch.
- Authored a video course for Packt Publishing about JavaScript.
Senior JavaScript Developer
Codete
- Developed an MVP in Angular for a German startup (video platform).
- Redesigned architecture and implemented from scratch an enterprise application with migration from jQuery legacy code to React and Redux, ES6, Immutable.js, and Webpack.
- Conducted a number of technical interviews for a JavaScript-related position.
- Developed the enterprise application for a Norwegian company (AngularJS).
Software Developer
Grape Up
- Mentored the front-end team (German startup) to redesign AngularJS architecture.
- Introduced AngularJS to the team of Apache Flex developers.
- Created a set of internal tools for fast project setup.
Co-founder
Young Da Vinci
- Created the company from scratch, including product prototyping, and hiring.
- Prepared and conducted a number of courses on programming dedicated to youngsters.
- Prepared and conducted a number of lectures for students.
Experience
Security Management System for High-risk Areas
http://jstrainings.com/security_system/video.htmlSkills
Languages
JavaScript, TypeScript, CSS, HTML, CSS3, HTML5, Less, Sass, SCSS, ECMAScript (ES6), GraphQL
Frameworks
Angular, WebApp, Next.js, Redux, Bootstrap, NestJS, Tailwind CSS, AngularJS
Libraries/APIs
React, RxJS, REST APIs, Node.js, NgRx, D3.js
Tools
JavaScript Testing, WebStorm, Webpack
Paradigms
REST, Web Architecture, API Architecture, Management
Other
Team Management, Architecture, Leadership, Technical Leadership, Third-party APIs, Third-party Integration, Front-end, Front-end Architecture, Web Development, API Integration, User Interface (UI), Material Design, Software Engineering, Team Leadership, APIs, Software Architecture, Front-end Development, Software, User Experience (UX), Startups, CTO, Accessibility
Platforms
Firebase, Amazon Web Services (AWS)
Storage
MongoDB
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