Felix Tellmann
Verified Expert in Engineering
Software Developer
Felix is a seasoned full-stack developer specializing in serverless architecture using React, Node.js, and TypeScript. He has recently published his second Shopify app catering to millions of merchants worldwide. As a passionate problem solver, Felix tackles complex challenges with patience, determination, and unrelenting persistence. He believes in continuous learning and stays up-to-date with best practices covering all aspects, from accessibility to performance.
Portfolio
Experience
Availability
Preferred Environment
TypeScript, React, Tailwind CSS, Next.js, SQL, IntelliJ IDEA, APIs, Serverless Architecture, Functional Programming, Front-end
The most amazing...
...thing I've built is my recently published Shopify app called Lunatag. Merchants can use it to create shop-the-look experiences anywhere on their eCommerce site.
Work Experience
Co-founder and Senior Full-stack Developer
Tellmann
- Launched over 15 eCommerce website migrations to Shopify for clients worldwide as the lead developer.
- Planned, developed, and published two serverless web applications built with React and Node.js, now available to millions of merchants on the Shopify app store.
- Created and maintained an open-source TypeScript library for handling API calls via REST and GraphQL to Shopify's popular admin API.
- Assisted in the hiring of new developers and helped grow the team by mentoring junior developers through pair programming, code reviews, and one-on-ones.
- Built several private microservice integrations to handle unique business logic, inventory management, and processing eCommerce sales.
- Provided extensive tech customer support to clients covering all aspects from DevOps, macOS support, Windows support, and relating to POS systems.
Co-founder and Managing Director
The Exchange (Pty) Ltd
- Envisioned and opened a 200-seater restaurant with my wife with a unique grill and burger theme at a beautiful spot on the Knysna lagoon.
- Covered all aspects of the restaurant, from creating the initial business plan to sourcing funding and day-to-day operations.
- Led project management, shop fitting, operations, and establishing a team of 35 employees during peak season with up to 800 guests per day.
- Handled all legal, IT, and financial responsibilities for the company.
- Supported the overall marketing strategy with graphic design and food photography. I also developed the restaurant's website.
- De-registered and properly closed the business in March 2020 due to the economic effects of COVID-19 on the tourism industry.
Senior Front-end Developer
Liquix (Pty) Ltd.
- Built custom Shopify themes for clients using Liquid, JavaScript, HTML5, and SASS.
- Assisted in hiring new developers and helped grow the team by mentoring junior developers through pair programming, code reviews, and one-on-ones.
- Developed the agency marketing site using React and Shopify as a headless CMS.
- Created documentation and coding standards for internal use across projects.
- Managed large-scale data migrations using database SQL queries and developed web scrapers for legacy systems.
- Improved test coverage by writing unit and integration tests with Jest and Enzyme.
Co-founder and Full-stack Developer
SmartUp Online (Pty) Ltd.
- Co-founded SmartUp Online (Pty) Ltd in 2016 as a SAAS restaurant training platform to provide high-quality training to restaurant workers in South Africa.
- Worked as the lead developer and content director for training material, developing the online platform using the LAMP stack, including Linux, Apache, MySQL, and PHP with an MVC architecture.
- Involved in the UX design process, providing feedback, discussing technical challenges, and performing qualitative user testing.
Front-end Developer
Self-employed
- Managed a portfolio of web projects for local businesses, helping to grow an online presence.
- Created websites from PSD design files and set up hosting via Apache servers and FTP access.
- Developed a React and Node.js-based internal dashboard to automate client requests and provide timely feedback.
- Built API integrations to handle internal business processes and automation, including web image processing.
General Manager
Kitima Restaurant
- Developed and opened a new restaurant in the center of Cape Town, where I grew a team of 1 to 25 employees and developed training manuals, operational systems, and service procedures for all aspects of the day-to-day operation.
- Oversaw all aspects of creating a new restaurant, including construction and shop fitting, set up of IT infrastructure and POS programming, and made the wine and cocktail list while working closely with the head chef to establish the food menu.
- Created and maintained a training program and information systems involving all food and beverage production. Upskilling over 80 employees over three years.
- Handled all web design, micros POS programming, and IT solutions for two restaurants.
- Ensured service standards were maintained at the highest level and assisted the front-of-house team by filling in where needed during peak operations.
- Contributed to the restaurant's success and helped the restaurant win several awards, including Best Asian Restaurant for Eat Out Magazine, Diamond Wine list award for times Diners Club, and The Bizz award for Excellence in Business Practices.
Experience
Lunatag
https://apps.shopify.com/lunatagI was the principal full-stack developer and had to meet the release timeline and deliver all core features. During the development, I established the algorithm to automatically match and position any image on the user's screen, regardless of the theme's internal setup.
I also developed a secure way to handle user authorization and created a proxy server to handle all route requests so users feel like they are visiting their own Shopify theme editor while being in the app's environment.
ClickUpload
https://apps.shopify.com/click-uploadI was the lead developer building most of the application with React, Node.js, AWS S3, and Turborepo. A core feature of the app is that it fully integrates into the merchants' theme editor and can easily be customized to suit any brand guide. The app's back-end side matches Shopify's admin dashboard to ensure that the user experience is frictionless.
Shopify API TypeScript Library
https://www.npmjs.com/package/shopify-typed-node-apiI developed the open-source library in parallel to a private app where it was essential to have full type safety for all data queried from the API. The package includes all types for each of the REST admin, APIs, and a generator for any GraphQL query and mutation that a simple CLI command can run.
Ecommerce Store for Volkswagen
https://www.southernseamotors.co.za/Another major component of the project was training the Volkswagen employees to manage and maintain the site, adding new vehicles and parts to their product catalog.
Skills
Languages
TypeScript, HTML, CSS, JavaScript, HTML5, SQL, SCSS, GraphQL, Ruby, Python, PHP 7, PHP
Frameworks
Tailwind CSS, Next.js
Libraries/APIs
React, Liquid, Node.js, Shopify API, CSSinJS, Preact, Libraries/APIs
Tools
IntelliJ IDEA, Prisma, Illustrator CC, GitHub, Postman, Git, Photoshop CC, Webpack, Babel, Gulp, Grunt, JSX, NPM, Figma
Paradigms
Functional Programming, REST, Serverless Architecture, Agile Project Management, Management, UX Design, DevOps, MVC Design, HTML DOM, Testing
Platforms
Shopify, Windows, Vercel, Amazon Web Services (AWS), WordPress, Linux
Storage
JSON, PostgreSQL, SQL Server DBA, Database Architecture, Amazon S3 (AWS S3)
Other
tRPC, Front-end, Serverless, APIs, ESLint, Microsoft Office, Entrepreneurship, Lean Startups, Business Psychology, Information Systems, Content Management Systems (CMS), Organizational Behavior (OB), Vector Design, Customer Service, Business Management, Total Quality Management (TQM), Project Planning, Event Management, Point-of-Sale (POS) Systems, Reservation Flow, Recipes & Cooking, Operations Management, Inventory Management, Food Safety, Food & Beverage, Project Coordination, FTP, App UX, Recipe Development, Human Resources (HR), Point of Sale, Training & Training Content Development, Team Building, IT Support, Content Creation, Restaurants & Dining, Restaurant Operations, New Business Development, IT Services, eCommerce Management, Web Development, User Authentication, Authentication
Education
Postraduate Diploma in Business Management and Entrepreneurship
University of Cape Town - Cape Town, South Africa
Bachelor's Degree in Hotel and Hospitality Management
International Hotel School - Cape Town, South Africa
Bachelor's Degree in Professional Cookery and Kitchen Management
International Hotel School - Cape Town, South Africa
Certifications
Business Fundamentals Certification
Shopify
React Certification
CodeCademy
Back-end Developer Certification
FreeCodeCamp
Product Fundamentals Certification
Shopify
App Development Certification
Shopify
Theme Development Certification
Shopify
Front-end Developer Certification
FreeCodeCamp
Skills, Tasks, and Result Training
International Hotel School
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