Lukas Klinzing
Verified Expert in Engineering
Full-stack Developer
Vienna, Austria
Toptal member since March 10, 2022
Lukas is an accomplished full-stack engineer with 16 years of experience developing applications and scalable infrastructures for global startups and big enterprise corporations. His primary focus is on creating exceptional UI-heavy web applications and AI-based software. Lukas has a profound understanding of business requirements and can adeptly turn them into user-friendly solutions. He is committed to continuous self-improvement and supporting colleagues in reaching their full potential.
Portfolio
Experience
- JavaScript - 14 years
- TypeScript - 7 years
- React - 7 years
- Serverless - 5 years
- User Experience (UX) - 5 years
- Figma - 5 years
- Docker - 5 years
- Continuous Delivery (CD) - 4 years
Availability
Preferred Environment
Visual Studio Code (VS Code), Docker, Figma, React, TypeScript, NestJS, REST, GraphQL, Firebase, Windows
The most amazing...
...thing I've developed is a high-performance price editing tool for the biggest sports activity platform to maintain thousands of prices of various activities.
Work Experience
Designer | Full-stack Engineer | Architect
Focusflow.ai
- Created a simple and engaging landing page for FocusFlow, a personal habit and activity tracker powered by AI.
- Leveraged Firebase to complete the MVP project in just two weeks with lightning speed.
- Built the application using atomic design principles on a robust React UI framework, enabling efficient and consistent development.
Senior Lead Front-end Engineer
CheckYeti
- Took ownership of DevOps, E2E testing, TypeScript migration, system design, private package management, and learning sessions.
- Introduced a TypeScript migration plan and migrated over 50% of code within four months.
- Established the weekly learning and mobile programming sessions to improve and align on coding style.
- Reduced user acceptance testing effort by introducing an E2E testing framework and pipeline.
- Introduced a system design and defined a plan to standardize all significant components in an atomic design style.
- Rebuilt the complete checkout, including the booking and payment process.
- Built an advanced price editing tool for defining granular, non-linear prices.
- Designed an architecture with private package management to combine and reuse cross-application design and functionality.
UX Designer | Senior Full-stack Engineer
Freelance
- Built a scalable social marketing machine that delivers around one million emails and social network notifications daily.
- Designed and implemented several custom solutions for a content management system.
- Built the highly advanced admin user interfaces to manage dynamic content, email marketing campaigns, and email delivery schedule.
- Migrated multiple projects from JavaScript to TypeScript in a continuous and well-defined migration plan.
- Established end-to-end tests into existing systems to confidently upgrade to newer solutions.
- Built the reusable frameworks for smart systems like smart TVs and smart mirrors.
Smart TV Developer
Freelance
- Built multiple smart TV apps for a range of companies, including RTVE.
- Invented a directional layout management system similar to today's well-known Flex system in CSS.
- Invented a smart TV-based directional navigation and focus system that allowed the automatic focus of elements. It used the directional layout management technique to understand which elements are visually next to each other.
Full-stack Developer
OEWP
- Co-founded the company with the idea to build an Austrian-wide company network (B2B) which could help connect companies.
- Designed the system and architecture, based on .NET and ASP.NET Forms and jQuery for the front end.
- Invented a visual on-page editing content management system which was revolutionary at the time. The website allowed the drag and drop components, written in ASP.NET Form controls into slots.
- Implemented a back-end system allowing to define content models. This automatically created CRUD pages to create, read, update and delete content.
- Managed a team of content editors that used my CMS to fill the website with around 200.000 company information from Austria.
Experience
Shopping Cart for Activities and Rental
http://www.checkyeti.comDISCOVERY PHASE AND UX DESIGN
We ensured everyone understood the customer's purpose and requirements during the discovery phase. After that, the project's planning began, and solutions for the user experience were designed.
SHOPPING CART
In the MVP, we built first a rental addon cart, which allowed the user to add rental equipment to his selected activity.
CHECKOUT
I rebuilt the checkout from the ground up to support multiple products for the booking, which included customer details, participant information, rental shop pickup selection, and the payment process itself.
Product Management and Price Editing
http://www.checkyeti.comThe prices depended on start times, group or private lessons, custom duration options, the number of participants, and selected activity durations for each provider.
PERIOD MANAGEMENT
Each activity provider can manage periods when providing ski course activities within the year. For this, a CRUD application was created.
PRODUCT AND DURATION MANAGEMENT
Each provider can manage their offering, including basic information about the product. Also, each product is enriched with duration options that describe how long a course takes place. The provider can have both private and group offers, usually from several hours to multiple days. For this, a management application was created.
PRICING MANAGEMENT
Since the prices depended on many aspects, such as duration option, period, and the number of days or participants, a sophisticated tool was created, allowing granular but efficient price editing. The keyboard navigation was enabled to enhance productivity so that the provider could navigate quickly between all the different prices and surcharges.
Knowledg.io | Prompt Management and AI Workflows
http://knowledg.ioFocusflow.ai | Self-improvement SaaS
https://focusflow.aiEmail Marketing Management Software
SEGMENTATION
The marketer can create individual user segments with highly advanced filtering UI. The software can handle hundreds of thousands of users grouped in those segments.
EMAIL CREATION
Visual tool to build custom emails with reusable blocks and intuitive variable placement to enable highly individual emails.
SCHEDULING AND DELIVERY
The high-performance architecture allows to schedule around 500,000 emails across the day and delivers it to a dispatcher service such as Mandrill or SparkPost.
TRACKING AND ANALYTICS
Advanced tracking of events happening during delivery, opening, and clicking. The system can use analytics to put users into segments so that follow-up emails can be created and the user experiences a highly customized story flow. A dashboard displaying information about segments and campaigns gives insights into the success of the marketing activity.
Fintech Web Scraper and Syncer
Smart TV App and Framework
FRAMEWORK
I designed a layout framework and navigation logic that allowed directional navigation and focused on-screen elements. This framework allowed positioning elements similar to today's CSS flex layout logic. Based on the positioning, the navigation of directional keys could be calculated, and focusing was automated. Before this framework, programmers had difficulty figuring out what element should be focused on after hitting the arrow buttons.
APPLICATION
The application had multiple screens. Overview with categories and recently added videos, search screen, a detailed view of a video or a series of videos, and the video player itself.
SaaS for Generating Smart Contracts
SMART CONTRACT GENERATOR
After searching for some solutions, I found one where it is possible to generate and compile smart contracts from within a currently running smart contract. This allowed me to generate smart contracts from within my smart contract.
FRONT AND BACK END
The SaaS allows authentication of users and subscribing to services. It has a few landing pages, a user area with dashboards, and a small marketplace that allows generating customized smart contracts predefined with some templates.
Skills
Libraries/APIs
React, Backbone.js, Node.js, REST APIs, Delayed Job, Stripe, Puppeteer, jQuery, Entity Framework, Web3.js, OpenZeppelin, Auth, Google Speech API, Firebase Web SDK, Google Vision API, SendGrid API
Tools
Figma, Git, MetaMask, ChatGPT, Google AI Platform, Zapier, Notion, Spreadsheets, SendinBlue, SendGrid
Languages
TypeScript, PHP, JavaScript, SQL, CSS, HTML, Semantic HTML, GraphQL, Solidity, VB.NET
Frameworks
React Native, Redux, Next.js, Electron, Material UI, Express.js, Svelte, NestJS, Tailwind CSS, Cypress, JSON Web Tokens (JWT), .NET 3, ASP.NET, ASP.NET Web Forms, Jest, Hardhat
Paradigms
Continuous Delivery (CD), REST, Testing, DevOps, Automation
Platforms
Docker, Firebase, Vercel, Linux, Windows, Amazon Web Services (AWS), Ethereum, Visual Studio Code (VS Code)
Storage
MySQL, Cloud Firestore, SQLite, Google Cloud, PostgreSQL, MongoDB, Data Validation, Sync
Other
User Experience (UX), Serverless, Monorepos, System Design, Design Systems, Customer Data, Shopping Carts, Full-stack, APIs, Axios, SDKs, Integration, Cloud Infrastructure, SparkPost, Message Queues, Scheduling, Checkout, Payment APIs, Card Payments, Web Crawlers, Web Scraping, SaaS, Fintech, OAuth, Architecture, System Architecture, System Architecture Design, eCommerce, Payment Gateways, eCommerce APIs, Job Schedulers, Videos, Video Players, User Interface (UI), Smart TV, Navigation Design, Performance, Forms, Optimization, Ethers.js, Smart Contracts, Ethereum Smart Contracts, Cryptocurrency Wallets, OpenAI GPT-4 API, Remotion, Speech to Text, Speech Recognition, Generative Pre-trained Transformer 3 (GPT-3), Large Language Models (LLMs), Search, Embedded Systems, OpenAI GPT-3 API, Semantics, Milvus, Generative Pre-trained Transformers (GPT), Pinecone, Framer X, Framer, CSV, CSV Import, CSV Export, API Integration, App Integration, Natural Language Processing (NLP), Spreadsheet Automation, IT Automation, Task Automation, Chakra UI, LangChain, Email Marketing, Email Marketing Automation, Lemon Squeezy, MVP Design, Minimum Viable Product (MVP)
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