Jan Sustr

Full-Stack Developer

Frankfurt, Germany

I am a product-focused Full-Stack Developer with 8+ years of experience, building scalable, user-centric web applications that bridge the gap between complex backend logic and intuitive frontend design. Primarily utilizing Java, C#, Go, Typescript, React, Angular.

When I'm not coding, you can find me hiking, playing badminton, reading non-fiction literature, or experimenting with music production.

Contact Me

Email LinkedIn Open to opportunities
GitHub
Jan Sustr

Experience

  1. 06/2025 — Present

    Freelance Software Engineer · BookBetterDirect

    Architected and developed a cloud-native backend for a direct hotel booking navigator. Designed and managed infrastructure on Azure Container Apps with Fastify, implemented multi-environment CI/CD pipelines and estabilished SRE practices. Developed data processing pipelines in Python and a custom web browser extension.

    • TypeScript
    • Python
    • Node.js
    • Azure
    • Fastify
    • MSSQL
    • MySQL
  2. 02/2023 — 05/2025

    Integration Engineer · Celonis

    Maintained and enhanced top-tier integrations on Make.com (global iPaaS, 6M+ visits). Developed integrations involving Databases, AI Agents, and Cloud Infrastructure (AWS, Terraform, Pulumi, Kubernetes).

    • TypeScript
    • Python
    • Node.js
    • Kubernetes
    • AWS
    • MongoDB
    • Terraform
    • Pulumi
  3. 10/2021 — 12/2022

    Full-stack Developer · Unicorn

    Contributed to front-end and back-end development on 4 projects for the energy sector.

    • Java
    • TypeScript
    • Node.js
    • Spring
    • React
    • MongoDB
    • PostgreSQL
    • Docker
  4. 07/2020 — 06/2021

    Full-stack Developer · KMB Systems

    Designed and developed a multi-tenancy backend and interactive data visualization frontend for energy data analysis.

    • C#
    • TypeScript
    • ASP.NET Core
    • Angular
    • NgRx
    • DevExpress
  5. 11/2017 — 04/2020

    Full-Stack Developer (AI/ML Focus) · NanoTrix (R&D)

    Developed angular web UI for keyword spotting tasks. Created Python/Node.js automation scripts for data correction and system evaluation tools with Electron.js.

    • C/C++
    • Python
    • TypeScript
    • Go
    • MATLAB
    • Angular
    • Node.js
    • Electron.js

Personal Projects

  • WebGPU Game Engine

    High-performance 3D engine built from scratch with TypeScript and WebGPU. Features a modular ECS architecture, optimized rendering with automatic batching/instancing, and a custom WGSL shader preprocessor.

    • TypeScript
    • WebGPU
    • WGSL
    • ECS
    • 3D Graphics

  • Flashcard Learning Platform

    Full-stack PWA built with React 19 and Go. Features an offline-first sync engine with Firestore, SM-2 spaced repetition algorithm, and 3D animations (Framer Motion). Infrastructure managed with Terraform and Docker.

    • React
    • Go
    • Firestore
    • PWA
    • Terraform
    • Docker
    • Framer Motion

  • Cloud Cost Killswitch & FinOps Automation

    An automated failsafe mechanism that monitors cloud expenditures in real-time, eliminating 'Bill Shock' through event-driven serverless architecture.

    • Terraform
    • Go
    • GCP
    • Serverless
    • FinOps
    • Event-Driven