Florian Ionescu, Developer in Kiel, Schleswig-Holstein, Germany
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Florian Ionescu

Verified Expert  in Engineering

Bio

Florian is a senior full-stack software engineer with a decade of experience maintaining and expanding administrative business software. He's used to delivering critical features on tight deadlines and solving emergencies in complex code bases. Proficient in several technologies, programming languages, and frameworks, Florian focuses on JavaScript and TypeScript (React, Next.js, Node.js, Svelte, and SvelteKit) and has extensive experience with PHP.

Portfolio

Antidefault
Svelte, SvelteKit, Docker, Kubernetes, Hetzner, SQL, PostgreSQL, GitHub, Git...
Tapmax
JavaScript, Full-stack, Software Architecture, QR Codes, Svelte, Docker, GitHub...
CAI International Inc
React, SQL, JavaScript, PHP, Sybase, Postman, Docker, Playwright, REST...

Experience

  • Linux - 10 years
  • SQL - 10 years
  • JavaScript - 10 years
  • Docker - 7 years
  • React - 5 years
  • Node.js - 4 years
  • Amazon Web Services (AWS) - 2 years
  • Svelte - 1 year

Availability

Full-time

Preferred Environment

Linux, Git, Docker, Node.js, Amazon Web Services (AWS), Svelte, PostgreSQL, Kubernetes

The most amazing...

...thing I've developed from the ground up is a smart home system, including an administrative web app, custom hardware, and AI integration.

Work Experience

Lead Full-stack Software Engineer

2024 - PRESENT
Antidefault
  • Designed and animated 2D and 3D front ends for business clients using Tailwind, Three.js, WebGL shaders, GSAP, and SVGs in Inkscape.
  • Developed business websites as full-stack SvelteKit apps in tight feedback loops with customers using Agile methods.
  • Implemented CI/CD pipelines on GitHub to build Docker containers and push them to private container registries.
  • Deployed and managed several highly available Kubernetes clusters in production environments using Talos Linux, Ansible, and Terraform.
  • Monitored and maintained the websites deployed to the production Kubernetes clusters.
  • Analyzed risks and implemented prevention and recovery solutions to ensure GDPR compliance and data safety even during disasters.
Technologies: Svelte, SvelteKit, Docker, Kubernetes, Hetzner, SQL, PostgreSQL, GitHub, Git, Inkscape, Three.js, WebGL, JavaScript, Ansible, Terraform, OpenStreetMap, SVG, CSS, GSAP, GreenSock Animation Platform (GSAP), Amazon Web Services (AWS), General Data Protection Regulation (GDPR), GitLab CI/CD, CI/CD Pipelines, Shaders, Architecture, CTO, API Integration, REST APIs, DevOps, UI Design, Web Design, UX Design, 3D Graphics, GLSL, Computer Graphics, Vector Graphics, Data Privacy, Data Security, Compliance, Minimum Viable Product (MVP), Frameworks, Responsiveness, SaaS, User Experience (UX), B2B, Code Review, GitHub Actions, System Architecture, JSX, 3D Animation, Web Animation, Animation, UI Animation, Software Architecture, TypeScript, Front-end Architecture, Scalability, Search Engine Optimization (SEO), Server-side Rendering (SSR), Static Site Generators, Web Performance Optimization (WPO), Web Scalability, Application State Management, ECMAScript (ES6), Core Web Vitals, Lazy Loading, Accessibility, Startups, Web Accessibility, Amazon S3 (AWS S3), Responsive UI, Third-party APIs, Canvas, Front-end Design, API Development, Documentation, Continuous Integration (CI), Technical Leadership, SCSS, APIs, Back-end Development, Node.js, Testing, Front-end Development, A11Y, Figma, Tailwind CSS, RESTFul APIs, Microservices, Responsive Web Apps, Database Architecture, Software Engineering, Scalable Application, Vite, Leaflet, GreenSock, CRM APIs, Amazon Elastic Container Service (ECS), Cloud Infrastructure, Amazon RDS, Data Modeling, ECS, Infrastructure

Senior Full-stack Software Engineer

2023 - 2023
Tapmax
  • Developed a SaaS app according to client specifications, including user registration, QR code management and administrative features using a modern Svelte (SvelteKit, TypeScript, and JavaScript), Supabase (PostgreSQL), and Vercel stack.
  • Implemented a modern CI/CD process using Docker and GitHub Actions.
  • Documented the developed app and its CI/CD process to ensure a smooth transition to other developers.
  • Deployed the app via CI/CD to Vercel as a serverless application in both a staging and live environment.
Technologies: JavaScript, Full-stack, Software Architecture, QR Codes, Svelte, Docker, GitHub, Vercel, Supabase, Bootstrap, SQL, TypeScript, Serverless, Continuous Integration (CI), Continuous Delivery (CD), Architecture, API Integration, REST APIs, Minimum Viable Product (MVP), Frameworks, Responsiveness, SaaS, User Experience (UX), GitHub Actions, System Architecture, JSX, Front-end Architecture, Search Engine Optimization (SEO), Server-side Rendering (SSR), Static Site Generators, Web Performance Optimization (WPO), Web Scalability, Application State Management, ECMAScript (ES6), Core Web Vitals, Lazy Loading, Startups, Responsive UI, Third-party APIs, API Development, Documentation, SCSS, APIs, Back-end Development, Node.js, Front-end Development, RESTFul APIs, UI Design, UX Design, Responsive Web Apps, Database Architecture, Software Engineering, Vite, Data Modeling, Infrastructure

Senior Full-stack Software Engineer

2022 - 2023
CAI International Inc
  • Migrated screens of a macOS app to the web using React and JavaScript.
  • Implemented PHP REST API endpoints to connect the screens to the Sybase SQL database.
  • Met with stakeholders regularly to ensure alignment between product specs and stakeholder expectations.
  • Accompanied the product launch and addressed feature requests and issues as they arose.
Technologies: React, SQL, JavaScript, PHP, Sybase, Postman, Docker, Playwright, REST, REST APIs, Architecture, API Integration, DevOps, Frameworks, Responsiveness, User Experience (UX), Code Review, JSX, Software Architecture, Front-end Architecture, ECMAScript (ES6), Lazy Loading, Third-party APIs, API Development, APIs, Back-end Development, Testing, Front-end Development, RESTFul APIs, Software Engineering, Vite, Data Modeling, Infrastructure

Front-end Web Developer

2022 - 2022
Guild of the ROSE
  • Implemented the Big Five psychological evaluation using JavaScript, React, and Next.js, with its result displayed as a radar graph using Nivo.
  • Implemented the MetaPrompt tool with JavaScript, React, and Next.js used as a training and productivity tool.
  • Set up a reusable development environment with Docker Compose.
Technologies: JavaScript, Next.js, Docker, React, Docker Compose, API Integration, Frameworks, Responsiveness, User Experience (UX), JSX, Front-end Architecture, ECMAScript (ES6), Responsive UI, Third-party APIs, APIs, Front-end Development, RESTFul APIs, Software Engineering

Senior Full-stack Software Engineer

2019 - 2022
Stern & Schatz GmbH
  • Developed a new administrative system from the ground up using React and JavaScript to build a single-page application and Laravel and PHP 7 to provide a GraphQL API.
  • Migrated the legacy system seamlessly to the new administrative system by utilizing SQL views to integrate the old database while ensuring backward compatibility.
  • Integrated Amazon's MWS API to automate the administrative work to keep products and their stock in sync.
  • Incorporated the REST API by Mailchimp and the SOAP API by Mediafinanz to send payment warning emails to customers in specific time intervals and send claims to the collection department.
  • Led the development of a robust and encrypted backup system that used AES-256 and RSA for encryption.
  • Built a React and JavaScript component to track employees working time, vacation, and sick days.
Technologies: PHP, JavaScript, Laravel, React, GraphQL, SQL, Docker, Debian, Linux, CSS, HTML, Sass, APIs, Web Development, Full-stack, Integration, CSS3, User Interface (UI), Back-end, Object-oriented Programming (OOP), REST APIs, MySQL, LAMP, Front-end, Front-end Development, Automation, Software Development, Apollo, Docker Compose, Dashboards, Data Visualization, jQuery, HTML5, Ubuntu, PhpStorm, Algorithms, Data Structures, Programming, Python, Git, Less, Test-driven Development (TDD), Storybook, React Testing Library, PHPUnit, Component-based Development, Component-based Architecture, Design Patterns, Design Principles, Material UI, Back-end Development, REST, eCommerce, PHP 7, Software Architecture, Clean Code, Unit Testing, Full-stack Development, Databases, Responsive Web Design (RWD), MVP Design, Database Design, Relational Databases, API Integration, Frameworks, Responsiveness, User Experience (UX), JSX, Front-end Architecture, ECMAScript (ES6), Responsive UI, Third-party APIs, API Development, GraphQL API, RESTFul APIs, Database Architecture, Software Engineering, Data Modeling, Infrastructure

Mid-level Full-stack Software Engineer

2016 - 2019
Stern & Schatz GmbH
  • Set up a reusable development environment with Docker Compose.
  • Debugged several emergencies in the live legacy system using jQuery, JavaScript, and PHP.
  • Refactored PHP4 code to cut down on maintenance costs, reducing time spent on periodic changes by over 95%.
Technologies: JavaScript, Linux, Ubuntu, Debian, PhpStorm, Docker, Docker Compose, SQL, PHP, Algorithms, Data Structures, Programming, Git, REST APIs, Front-end, Front-end Development, Software Development, APIs, CSS, Less, HTML, Sass, Web Development, Full-stack, Integration, CSS3, User Interface (UI), Back-end, Object-oriented Programming (OOP), MySQL, LAMP, Dashboards, Data Visualization, jQuery, HTML5, Design Patterns, Design Principles, Back-end Development, REST, eCommerce, PHP 7, Software Architecture, Clean Code, Full-stack Development, Databases, Responsive Web Design (RWD), MVP Design, Database Design, Relational Databases, API Integration, Frameworks, Responsiveness, User Experience (UX), JSX, Front-end Architecture, ECMAScript (ES6), Responsive UI, Third-party APIs, API Development, RESTFul APIs, Database Architecture, Software Engineering

Junior Full-stack Developer

2014 - 2016
Stern & Schatz GmbH
  • Created a JavaScript webmail client and its PHP API, which most employees now use daily.
  • Developed a documentation system with JavaScript and PHP used daily by all employees to organize messages, files, and tasks in threads.
  • Implemented bug fixes and features based on assigned tickets.
Technologies: JavaScript, Linux, Ubuntu, Debian, PhpStorm, Docker, Docker Compose, SQL, PHP, Algorithms, Data Structures, Programming, Git, REST APIs, Front-end, Front-end Development, Software Development, APIs, CSS, HTML, Web Development, Full-stack, Integration, CSS3, User Interface (UI), Back-end, Object-oriented Programming (OOP), MySQL, LAMP, Dashboards, Data Visualization, jQuery, HTML5, Back-end Development, REST, eCommerce, Full-stack Development, Databases, Responsive Web Design (RWD), Database Design, Relational Databases, API Integration, Frameworks, Responsiveness, User Experience (UX), Front-end Architecture, ECMAScript (ES6), Responsive UI, Third-party APIs, API Development, RESTFul APIs, Database Architecture, Software Engineering

Experience

Antitether

Connection agnostic knowledge base software. It's developed to allow companies to deploy knowledge base software in their infrastructure and cloud and set up connections to LLMs, vector storage, and databases of their choice. Alternatives are hosted by the service provider or force connections to specific services, risking business data transmission to unknown or unwanted 3rd parties. Antitether, by being deployed and connected to services the company chooses, avoids this issue by design and allows compliance with, e.g., HIPAA or Soc2.

Smart Home System

I developed a smart home system from the ground up.

The system administration app is built as a React SPA with a PHP back end, providing a REST API. This API was then used by hardware components like lamps, switches, and laser barriers based on the ESP8266 and programmed with Arduino. The hardware was designed in Eagle, soldered together from PCBs and surface-mounted components, and put into 3D-printed cases designed in OpenCAD.

In addition, the system used Raspberry Pis to monitor rooms and detect people, which triggered an event that was used to automatically keep the lights (Philips Hue) on only in rooms with people.

Self-modifying Game Engine

A Node.js (TypeScript) turn-based game engine. It is used in developing a game where the game state overwrites the rules of the game itself. The focus lies on long-term maintainability while allowing any complexity to emerge from interacting rules-overwrites.

Antidefault CRM

A simple CRM for the purpose of preventing decay in personal relationships by notifying users of reaching out to a different set of people each day. I built it from the ground up using a Svelte (SvelteKit, TypeScript, and JavaScript), Vercel, and Supabase (PostgreSQL) stack and managed the development using a modern CI/CD process based on Docker and GitHub Actions. Payments were integrated using Stripe's subscription webhooks.

Comparison of Machine Learning Algorithms in the Context of EvoMan

Implementation and benchmarking of machine learning algorithms in the context of the game EvoMan.

This Python project used four machine learning algorithms, NeuroEvolution of Augmenting Topologies, Deep Q-Network, Advantage Actor-Critic, and REINFORCE, to compare their performance in the context of the open-source game EvoMan. First, the agents were trained against a pre-programmed AI, and then their performance was measured against that AI and against each other.

Udacity Blockchain Capstone Project

Developed and deployed an NFT smart contract on Goerli using zero-knowledge proofs to validate the NTF's minting. This project was a proof of concept in the context of a Udacity Nanodegree program in Blockchain development and could be further expanded into a complete Web3 marketplace (e.g., real estate).

Education

2014 - 2021

Bachelor's Degree in Computer Science

Christian-Albrecht University of Kiel - Kiel, Germany

Certifications

JANUARY 2022 - PRESENT

Blockchain Developer | Nanodegree Program

Udacity

Skills

Libraries/APIs

React, REST APIs, jQuery, Node.js, Three.js, API Development, Web3.js, React Testing Library, WebGL, GSAP, OpenAI API, Playwright, TensorFlow, Graph API, Stripe, Stripe API, GraphQL API, Leaflet

Tools

Git, GitHub, JSX, Canvas, PhpStorm, Docker Compose, LaTeX, GitLab CI/CD, GreenSock, Postman, Prisma, Auth0, Amazon Elastic Container Registry (ECR), Amazon Elastic Container Service (ECS), Audacity, Inkscape, Ansible, Terraform, Figma

Languages

GraphQL, SQL, PHP, JavaScript, CSS, HTML, CSS3, HTML5, PHP 7, TypeScript, ECMAScript (ES6), Solidity, Python, Less, Sass, GLSL, SCSS

Paradigms

Automation, Object-oriented Programming (OOP), REST, Database Design, Web Performance Optimization (WPO), Test-driven Development (TDD), Component-based Development, Design Patterns, Clean Code, Unit Testing, Responsive Web Design (RWD), Continuous Integration (CI), DevOps, UI Design, UX Design, B2B, Search Engine Optimization (SEO), Testing, Microservices, Scalable Application, Continuous Delivery (CD), Web UI Design, Web UX Design

Platforms

Docker, LAMP, Linux, Ubuntu, Debian, Blockchain, Arduino, Amazon Web Services (AWS), Vercel, Kubernetes, GreenSock Animation Platform (GSAP), Amazon EC2

Storage

MySQL, Databases, Relational Databases, PostgreSQL, Database Architecture, Sybase, Amazon S3 (AWS S3)

Frameworks

Truffle, PHPUnit, Material UI, Next.js, Svelte, Bootstrap, Laravel, Express.js, Tailwind CSS

Industry Expertise

Web Design

Other

Algorithms, Data Structures, Programming, Front-end, Front-end Development, Software Development, APIs, Web Development, Full-stack, Integration, User Interface (UI), Back-end, Dashboards, Back-end Development, Software Architecture, Full-stack Development, MVP Design, CI/CD Pipelines, Web Project Management, Architecture, API Integration, Minimum Viable Product (MVP), Frameworks, Responsiveness, SaaS, User Experience (UX), 3D Animation, Front-end Architecture, Scalability, Static Site Generators, Web Scalability, Lazy Loading, Responsive UI, Third-party APIs, Front-end Design, Documentation, RESTFul APIs, Software Engineering, Data Modeling, ESP8266, Apollo, Data Visualization, Storybook, Component-based Architecture, Design Principles, eCommerce, Smart Contracts, OpenAI GPT-4 API, OpenAI GPT-3 API, AI Integration, SvelteKit, Hetzner, SVG, Shaders, CTO, Vector Graphics, Data Privacy, Large Language Models (LLMs), Cryptocurrency, OpenAI, Prompt Engineering, Artificial Intelligence (AI), Code Review, GitHub Actions, System Architecture, Web Animation, Animation, UI Animation, Server-side Rendering (SSR), Application State Management, Core Web Vitals, Accessibility, Startups, Web Accessibility, AI Chatbots, Chatbots, Compliance, Data Security, Responsive Web Apps, Vite, CRM APIs, Cloud Infrastructure, Infrastructure, Machine Learning, LangChain, WebSockets, QR Codes, Supabase, Serverless, Webhooks, OpenStreetMap, General Data Protection Regulation (GDPR), Design, Website Design, Web3, 3D Graphics, Computer Graphics, Technical Leadership, A11Y, Amazon RDS, ECS

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