Andreas Kater, Developer in London, United Kingdom
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Andreas Kater

Verified Expert  in Engineering

Software Developer

London, United Kingdom
Toptal Member Since
October 25, 2018

Andreas is an experienced full-stack developer with a focus on Node.js and React. He has been the COO of three tech start-ups in London, most recently for an NLP consultancy partnered with Google Cloud Platform and Twilio. Andreas has also been a management consultant which gives him a lot of experience in senior stakeholder management. He holds an MBA from INSEAD.


Dar Al Nukhbah Electronics TR LLC
Google Maps API, TypeScript, React, WebRTC, REST APIs, Git, GitHub, Jest...
Revcontent LLC
React, Front-end, CSS, Node.js, APIs, Git, AWS Cloud Architecture, Twilio API...
Entrepreneur First
JavaScript, Node.js, React, Redux, Google Cloud Platform (GCP), Git, CTO...




Preferred Environment

Firebase, Visual Studio Code (VS Code), Google Cloud Platform (GCP), Node.js, React, TypeScript, Next.js, Twilio API, ChatGPT, Gmail API

The most amazing...

...thing I've coded is a CRM tool for a drone business that ensured the right pilot would be in the right place with the right equipment on the right day

Work Experience

Front-end React Developer

2022 - 2022
Dar Al Nukhbah Electronics TR LLC
  • Built a WebRTC connection to stream video from robot to UI for a robotic fleet management project.
  • Created a joystick to control the robot remotely that provided visual feedback on a tablet to allow users fine-grained control over the amplitude and direction of the instructions.
  • Built a custom Google Maps implementation that showed the robot fleet in Dubai with status, direction, and custom indoor overlays.
Technologies: Google Maps API, TypeScript, React, WebRTC, REST APIs, Git, GitHub, Jest, Full-stack, API Development, Express.js, Google Sheets

React Developer for Content Marketing Platform

2020 - 2021
Revcontent LLC
  • Designed and developed the rebuild of the company's client-facing API, including a thorough testing pipeline, API documentation, and very granular input validation with the JSON schema.
  • Designed and built the new front-end, using the newly built API and significantly reducing the legacy front-end's complexity, which had significantly slower load times.
  • Implemented a front-end component library with Bit, which would be the foundation of future design work to homogenize the brand across all online assets.
Technologies: React, Front-end, CSS, Node.js, APIs, Git, AWS Cloud Architecture, Twilio API, Stripe, GitHub, Full-stack, Amazon Elastic Container Service (Amazon ECS), API Development, Express.js, Cloud Run, Google Sheets, PDF

CTO for Business Automation Platform

2019 - 2020
Entrepreneur First
  • Built a business process automation platform that allowed customers to streamline and collaborate on complex business processes and automate them.
  • Designed and built a complex drag-and-drop flowchart interface that allowed the seamless editing of business processes.
  • Brought the project live and onboarded the first nine enterprise clients onto the tool.
Technologies: JavaScript, Node.js, React, Redux, Google Cloud Platform (GCP), Git, CTO, MongoDB, GitHub, Jest, Full-stack, Amazon Elastic Container Service (Amazon ECS), Team Leadership, Express.js, Cloud Run, Chatbots, Natural Language Processing (NLP), Generative Pre-trained Transformers (GPT), Google Cloud Datastore, Google Sheets, SVG, Gmail API, Architecture, Solution Architecture

Director of Business Operations

2018 - 2020
  • Automated our hiring pipeline by automatically assigning candidate interviews to members of the team based on their expertise and availability. Hired 14 people.
  • Automated our payroll calculation by building an expenses platform that worked across the four different geographies we had employees in.
  • Built an HR chatbot that gave team members quick answers like "How many holidays do I have?", "What is our maternity/paternity policy?", "Who is my line manager?", etc.
  • Obtained the ISO27001 Information Security certification to streamline our sales process with enterprise-level customers.
Technologies: React, Google Cloud Platform (GCP), Twilio, Dialogflow, Node.js, Data Architecture, ETL, WebRTC, Git, Twilio API, GitHub, Jest, Full-stack, Team Leadership, Chatbots, Generative Pre-trained Transformers (GPT), Natural Language Processing (NLP), Google Cloud Datastore, Google Sheets, Architecture, Solution Architecture


2017 - 2018
Hummingbird Technologies
  • Designed and developed an ERP platform for a drone business to ensure the right pilot is at the right time and place with the right drone and camera.
  • Designed the system that is used for coordination of flights, pilots' operational performance monitoring, automatic flight path programming, billing, and customer service.
  • Developed the system using Python's Flask framework and hosted the service on the Heroku server. The service has 60 weekly users that log in to schedule the flights for the week.
Technologies: Node.js, React, Google Cloud Platform (GCP), JavaScript, Salesforce, Pipedrive API, Google Cloud, Flask, Python, Data Engineering, Angular, Amazon Web Services (AWS), PostgreSQL, Google Maps API, Git, GitHub, Full-stack, Team Leadership, Chatbots, Generative Pre-trained Transformers (GPT), Natural Language Processing (NLP), Google Cloud Datastore, Google Sheets, Architecture, Solution Architecture


2016 - 2017
  • Built an automated customer self-service function that allowed customers to manage their loans independently.
  • Provided complex all-in-one account view using D3 for customer service team that reduced average call times by 30%.
  • Developed an automated email and SMS campaign for customers that needed to take actions on their account, allowing them to do so on the move.
Technologies: JavaScript, D3.js, Pandas, Python, PHP, Software Development, Git, Team Leadership, Fintech

Freelance Developer

2016 - 2016
  • Developed a tool to communicate demand forecast to riders.
  • Built visualization of weekly workloads in GoogleSheets.
  • Set up the Heroku server to run analysis and communicate results daily.
Technologies: Google Sheets API, Heroku, SQL, JavaScript, Python, Data Analysis, Material UI, Google Maps API, REST APIs, Git


2011 - 2014
Analysys Mason
  • Served as a management consultant building custom asset valuation models for mobile network operators.
  • Supported one of the UK mobile operators during the 3G spectrum auction.
  • Calculated the cost to supply each postcode in the UK with fiber broadband.
  • Determined the value of 200,000 mobile towers in Russia.
  • Led a team of five analysts in building an innovative valuation methodology in record time.
Technologies: GIS, Visual Basic for Applications (VBA), R

React-Redux App Showing Analytics for Advertising Platform

An advertising platform wanted to replace an old analytics platform with a modern React application that pulled information from their brand new API. Since the data sets were non-trivial and needed to be summarized into various views, the app made extensive use of redux and sagas. Some views required database queries that the API was not yet capable of, so I added endpoints to the Node.js Feathers back end and add that functionality to the API.

React/Next.js App Showing Map of Luxury Resort
A luxury resort wanted to relaunch their website with a map view showing what is on offer on their premises. I rebuilt their website using React and Next.js and added the map view. This is powered by the GoogleMaps JavaScript API and allows clicking on buildings to get more information about them below.

Ery-API is a Node.js-based CLI tool to give you quick access to the API calls you're looking for and it performs the OAuth flow for authorization with all Google APIs.

The idea is to never have to read API Docs again. Give it a go with:
npm i ery-api -g

360-degree Feedback Platform Built with Firebase and React

The business I was working for wanted to implement a 360-degree feedback platform, where no off-the-shelf solution did exactly what was required, so I built an app using Firebase and React that would allow users to pick the people they requested feedback from, collected this feedback, allowed managers to summarize it, and to ultimately set goals for each employee that were tracked over time; GCP and Google Cloud functions are used. Thanks to Firebase's real-time DB, comments were shared instantly across open tabs, which was important for the quick completion of the feedback cycle.

HR Chatbot

For a business I worked for, I created a Dialogflow based HR chatbot that allowed our team to get quick answers to questions like: "How do I submit an expense?", "How many holidays do I have left?", "What is our policy on XXX?", etc. I integrated it into a slackbot to give everyone in the business fast answers to questions on how we do things.


I built a server that allows you to snooze emails, but forwarding an email to, for example, "" or "" and getting a reply in the same email chain at the specified time. This helped our customer service team stay on top of customer accounts when delayed actions/follow-ups were required (This was before Gmail introduced the snooze function).

Language Learning Platform

I built a platform that helps you learn a language by translating an epub e-book word-for-word. This allows you to read a book in a language you are learning and always having the translation available if you don't know a word in it. The tool will also pronounce the word for you if you tap it and show you further information, such as the conjugation if it is a verb. As this was a Progressive Web App, it allowed you to read the books when you were offline.

Offline Tasks Tool

I built a tool that used a service worker to build a Progressive Web App that would work offline. The tool was designed to help you keep track of your tasks by allowing you to snooze tasks until the time came to take care of them.

Art Gallery ERP

I built an ERP tool for an art gallery that needed to track where certain pieces of art were stored, who had enquired/bid/purchased them and what invoices/communications were logged against them. The tool also had a front-end component that acted as the gallery's online presence.
2015 - 2015

Master's Degree in Business Administration

INSEAD - Singapore

2010 - 2011

Master of Science Degree in Management and Strategy

London School of Economics - London, United Kingdom

2006 - 2009

Bachelor of Engineering Degree in Mechanical Engineering

University of Nottingham - Nottingham, United Kingdom

APRIL 2022 - APRIL 2024

Professional Cloud Developer

Google Cloud


Node.js, React, Google Sheets API, Google Maps API, REST APIs, Twilio API, API Development, SQLAlchemy, Gmail API, jQuery, D3.js, WebRTC, Puppeteer, Stripe, Pipedrive API, Google Maps, Pandas, NumPy


Dialogflow, Git, Jira, GitHub, Prisma, BigQuery, Google Sheets, ChatGPT, Amazon Elastic Container Service (Amazon ECS), DataGrip, GIS


Realtime, Express.js, Next.js, Redux, Flask, Material UI, Jest, Angular, Tailwind CSS, FeathersJS


SQL, CSS, JavaScript, TypeScript, HTML, HTML5, Python, R, Visual Basic for Applications (VBA), PHP, Visual Basic


Agile, REST, Microservices, Search Engine Optimization (SEO), ETL, Test-driven Development (TDD)


Google Cloud Platform (GCP), Twilio, Firebase, Docker, Cloud Run, HubSpot, Amazon Web Services (AWS), Mapbox, Heroku, Salesforce, Visual Studio Code (VS Code)


NoSQL, MongoDB, MySQL, Google Cloud Datastore, PostgreSQL, Elasticsearch, Google Cloud


OAuth, APIs, Workflow, Cloud Architecture, Data Analysis, Data Architecture, Front-end, Architecture, Team Leadership, CTO, Full-stack, CI/CD Pipelines, Fintech, Key Performance Indicators (KPIs), Cloud Tasks, Full-stack Development, Chatbots, Natural Language Processing (NLP), Generative Pre-trained Transformers (GPT), OpenAI GPT-3 API, Styled-components, API Integration, SVG, Website Audits, Solution Architecture, Data Engineering, Software Development, Stock Trading, AWS Cloud Architecture, MERN Stack, Language Models, Single Sign-on (SSO), PDF, Command-line Interface (CLI), Google Cloud Functions

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