Sebastian is available for hire

Sebastian Wasser

Verified Expert in Engineering

Software Developer

Location

Warsaw, Poland

Toptal Member Since

January 6, 2021

Sebastian started working professionally as a software developer before finishing high school. This drive to apply his skills to solve problems jump-started his career, and to this day, it is the same driving force that he applies to his work every day. Sebastian excels in coming up with unconventional solutions to client problems: his clients' success is his ultimate goal.

Back-end Web Development Front-end Web Scraping Full-stack CSS JavaScript PHP REST APIs JSON Laravel HTML5 PHP 7 React Vue Shopify Theme Klarna API

Portfolio

Self-employed

Amazon Web Services (AWS), PHP 7, Flexbox, CSS2, CSS3, CSS, HTML5, HTML...

Dirtbikexpress Ltd.

Laravel, JavaScript, Tailwind CSS, APIs, Git, Braintree API, HTML5...

Revive GmbH

Amazon Web Services (AWS), Laravel Nova, Shopify, Vuex, Vue, PHP 7, PHP, NGINX...

Experience

JavaScript - 10 years PHP - 10 years Laravel - 9 years Linux - 8 years Vue - 4 years Docker - 4 years TypeScript - 3 years Tailwind CSS - 2 years

Availability

Part-time

Preferred Environment

Docker, Zsh, Google Chrome, Visual Studio Code (VS Code), MacOS

The most amazing...

...thing I developed was a highly configurable image management platform for managing product images in different shapes for various marketplaces with one click.

Work Experience

Senior Full-stack Developer

2018 - PRESENT

Self-employed

Developed several different applications and tools depending on client needs.
Tracked and fixed bugs using a self-hosted GitLab instance.
Supported and offered consultation to various clients to meet their technical needs.
Guided transition clients from legacy systems to more modern ones, including data migrations.
Found unconventional solutions to clients' niche problems.

Technologies: Amazon Web Services (AWS), PHP 7, Flexbox, CSS2, CSS3, CSS, HTML5, HTML, Composer, NGINX, MySQL, DigitalOcean, Server Administration, Tailwind CSS, Nuxt.js, Vue, Vuex, Laravel, Docker, GitLab CI/CD, Git, Bash, JavaScript, PHP, Back-end, Object-oriented Programming (OOP), Data Structures, REST APIs, Web Development, TypeScript, React, GraphQL, Jest, Unit Testing, Node.js, NPM, Shopify API, Full-stack, Liquid, DOM, Next.js, API Integration, RESTful Web Services, Payment APIs, Online Payments, Full-stack Development, Front-end, Search Engine Optimization (SEO), SQL, Redux, Back-end Development, REST, Cypress, Integration Testing, SEO Tools, Themes, PostgreSQL, CI/CD Pipelines, Figma, GitHub, Architecture, eCommerce, RESTful Services, JavaScript Testing, Mobile First, Mobile Apps, Liquid Template, Responsive Web Design (RWD), User Experience (UX), User Interface (UI), Content Management Systems (CMS), JSON, Single-page Applications (SPA)

Full-stack Developer

2021 - 2023

Dirtbikexpress Ltd.

Scoped the project after assessing the initial list of required features and proposed improvements based on those features.
Established clear development flows to be incorporated with the development team and the business stakeholders, e.g., Jira for ticketing and Bitbucket with a well-defined Git flow for source code management.
Gave UX and UI improvement tips for the storefront to maximize the conversion rate.
Implemented eCommerce storefront from start to finish, including clever solutions for more specific business needs.
Implemented large parts of the back-end functionality and the warehousing management software (including order fulfillment) for the company's employees.

Technologies: Laravel, JavaScript, Tailwind CSS, APIs, Git, Braintree API, HTML5, Blade Templates, Vue, Vite, Composer, CSS, Inertia, Back-end, Object-oriented Programming (OOP), Data Structures, REST APIs, Web Development, TypeScript, Full-stack, DOM, API Integration, RESTful Web Services, Payment APIs, Online Payments, Full-stack Development, Front-end, Search Engine Optimization (SEO), SQL, Back-end Development, REST, Cypress, Integration Testing, Themes, CI/CD Pipelines, GitHub, Architecture, eCommerce, RESTful Services, JavaScript Testing, Mobile First, Jira, Responsive Web Design (RWD), User Experience (UX), User Interface (UI), Content Management Systems (CMS), JSON, Single-page Applications (SPA)

Lead Developer | Independent Contractor

2016 - 2021

Revive GmbH

Developed many small and medium-sized applications and tools to improve workflows and increase efficiency in every part of the company.
Advised the management on technical decision-making and steps to take.
Oversaw major platform and data migrations when the existing solutions stopped being viable due to the company's growth.
Moved their webshop from WooCommerce as a platform to Shopify.
Tweaked the existing Shopify theme to do exactly as the client wanted, including previously completely unsupported features.

Technologies: Amazon Web Services (AWS), Laravel Nova, Shopify, Vuex, Vue, PHP 7, PHP, NGINX, MySQL, Linux, Laravel, jQuery, JavaScript, HTML5, HTML, Google Vision API, GitLab CI/CD, Git, Flexbox, Bash, Docker, DigitalOcean, DevOps, CSS2, CSS3, CSS, Composer, Back-end, Object-oriented Programming (OOP), Data Structures, REST APIs, Shopify Design, Shopify Theme, Web Development, Shopify Customizations, TypeScript, Shopify API, Full-stack, DOM, API Integration, RESTful Web Services, Payment APIs, Online Payments, Full-stack Development, Front-end, Search Engine Optimization (SEO), SQL, Back-end Development, REST, Cypress, Integration Testing, SEO Tools, Themes, CI/CD Pipelines, GitHub, Architecture, eCommerce, RESTful Services, JavaScript Testing, Mobile First, Mobile Apps, Liquid Template, Liquid, Responsive Web Design (RWD), Content Management Systems (CMS), JSON

CTO and Full-stack Developer

2016 - 2017

German Angel Initiative gUG (haftungsbeschränkt)

Conceptualized and developed an application to aid the onboarding process for prospective members.
Worked closely with all stakeholders to create an intuitive and productive tool.
Reacted swiftly to required changes while the company was evolving and growing.

Technologies: Laravel, jQuery, Semantic UI, PHP, Back-end, Object-oriented Programming (OOP), Data Structures, Web Development, Full-stack, DOM, API Integration, Project Management & Work Tracking Tools, Full-stack Development, Front-end, SQL, Back-end Development, REST, PostgreSQL, GitHub, Architecture, Jira, Mobile Apps, Responsive Web Design (RWD), JSON, Single-page Applications (SPA)

PHP Developer

2012 - 2015

R&E Media

Developed and maintained a WordPress instance to serve over 6 million monthly active users worldwide.
Tracked and fixed bugs reported by the internal team in YouTrack initially and later in Jira.
Developed and maintained data importers, crawlers, and other means of fetching data, which were then processed and integrated into a WordPress-based system.
Helped maintain the internal infrastructure, especially with regard to the Git server on the in-house server.

Technologies: Git, Agile Software Development, WordPress, JavaScript, Back-end, Object-oriented Programming (OOP), Data Structures, REST APIs, Web Development, Full-stack, DOM, API Integration, RESTful Web Services, Project Management & Work Tracking Tools, Full-stack Development, Front-end, SQL, Back-end Development, REST, SEO Tools, Themes, PostgreSQL, GitHub, RESTful Services, Jira, Responsive Web Design (RWD), Web Scraping, Content Management Systems (CMS), Affiliate Marketing, Coupons, JSON, Single-page Applications (SPA)

Experience

Product Image Management Platform

A front-end-centric app to set up and maintain images in various resolutions, with various overlays and other specifications.

I was tasked with the development of an app to automatically detect a product images core (the product itself), categorize it and crop and scale the image according to per-marketplace based, differing configurations, and add various necessary overlays, such as product manufacturer logos, category, and product-specific text overlays and more.

The app had to be as automated as possible while retaining the highest possible flexibility regarding the image size, overlays, and positioning on the marketplace. Additionally, it had to be as performant as possible, not collapse users' browsers, and not overuse their internet bandwidth when uploading the images and maintaining (after saving) them.

Custom eCommerce Storefront and Warehousing Software

An all-around custom solution to provide an extensible and technologically up-to-date platform to provide a storefront to customers as well as warehousing management and order fulfillment to stakeholders from various departments. My role ranged from scoping the requirements to building back-end and (especially) front-end parts of varying complexity to solve industry- and client-specific problems and establish improved efficient internal processes.

Purchase Form

A purchase form for customers to input data regarding furniture pieces they want to sell to be repaired and refurbished before being sold again. The form ensures that all data entered is correct and facilitates entering the (future) product into the warehouse management software and storefront along the line.

Minesweeper Game

https://github.com/sebwas/minesweeper

A React (TypeScript) based version of the classic Minesweeper game. It is a project to highlight and showcase my ability to manage a project and the used technologies and methodologies, such as React, TypeScript, progressive web applications (PWA), Git, and testing.

Skillset

Languages

JavaScript, PHP, TypeScript, HTML, CSS, HTML5, CSS3, PHP 7, SQL, Liquid Template, XML, Bash, CSS2, ECMAScript (ES6), GraphQL

Frameworks

Laravel, Nuxt.js, Tailwind CSS, Next.js, Redux, Lumen, Jest, Cypress

Libraries/APIs

Vue, React, REST APIs, jQuery, Vuex, Node.js, Liquid, Google Vision API, Flexbox, React Router, Braintree API, Inertia, Shopify API

Paradigms

Object-oriented Programming (OOP), REST, Agile Software Development, Unit Testing, Search Engine Optimization (SEO), Responsive Web Design (RWD), Testing, DevOps, Kanban, Scrum

Storage

JSON, MySQL, PostgreSQL

Other

Full-stack, PHP 8, Back-end, Web Development, DOM, API Integration, Front-end, RESTful Services, Web Scraping, Vue Router, i18n, APIs, Data Structures, Shopify Theme, Shopify Customizations, RESTful Web Services, Full-stack Development, Back-end Development, Integration Testing, SEO Tools, Themes, eCommerce, Mobile First, Content Management Systems (CMS), Affiliate Marketing, Coupons, Single-page Applications (SPA), Semantic UI, Server Administration, Service Workers, Laravel Nova, Deno, Blade Templates, Vite, Apple Pay, Klarna, Shopify Design, Project Management & Work Tracking Tools, Payment APIs, Online Payments, CI/CD Pipelines, Architecture, Mobile Apps, User Experience (UX), User Interface (UI), UI Testing, PWA, Progressive Web Applications (PWA), Algorithms

Tools

Git, GitHub, JavaScript Testing, GitLab CI/CD, NGINX, Composer, NPM, Figma, Jira

Platforms

WordPress, Linux, Shopify, Docker, DigitalOcean, Amazon Web Services (AWS), MacOS

Education

2013 - 2015

Coursework in Computer Science

Rheinische Friedrich-Wilhelms-Universität Bonn - Bonn, Germany

Certifications

JULY 2018 - PRESENT

Certified Laravel Developer

Laravel LLC

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