James Lambert, Developer in London, United Kingdom
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James Lambert

Verified Expert  in Engineering

Minimum Viable Product (MVP) Developer

London, United Kingdom
Toptal Member Since
November 7, 2022

After his PhD, James worked as a private tutor for 10 years. He founded Inspired Minds in 2016, which ran programming and robotics-themed events for children and adults. James and his business partner raised seed funding to explore space propulsion concepts, and Pulsar Fusion was born in 2019. James splits his time between programming and running Pulsar and its many academic collaborations and hardware projects. He loves getting involved in original projects, often based on hardware.


Pulsar Fusion
Python 3, Pandas, Jupyter, Matplotlib, NumPy, Flask, SQL, React, JavaScript...
Pulsar Fusion
JavaScript, Flask, SQL, Arduino, Pandas, Git, NumPy, Matplotlib, Python, React...
Openset Ventures
C++, Arduino, HTML, CSS, Python 3, Pandas, Jupyter, Matplotlib, SciPy, NumPy...




Preferred Environment

SQL, Python, NumPy, Pandas, Swift, REST APIs, Hardware, Architecture, Proof of Concept (POC), Minimum Viable Product (MVP)

The most amazing...

...project I've worked on is a rocket engine combined with a fuel feed system. My team designed the hardware and software control systems from scratch.

Work Experience

Senior Software Developer

2019 - PRESENT
Pulsar Fusion
  • Built and designed a React front-end to control and test rocket systems. Used React, JavaScript, Node.js, and CSS to build a simple and responsive control panel that allows engineers to test devices in an easy-to-use/hard-to-misuse way.
  • Designed, built, and developed the control logic back-end for rocket systems using Python, Flask, NumPy, and SQL.
  • Created and developed an iOS app for measuring magnetic fields. This app allowed engineers to quickly and conveniently verify that components were wired correctly without using a bulky testing kit. Used SwiftUI and CoreMotion.
Technologies: Python 3, Pandas, Jupyter, Matplotlib, NumPy, Flask, SQL, React, JavaScript, Node.js, Arduino, C++, Proof of Concept (POC), Mobile Development, MySQL, JSON Web Tokens (JWT), REST APIs, Embedded Systems, Microcontrollers, Hardware, Architecture, ESP32, Team Leadership, HTML, UI Animation, User Interface (UI), User Experience (UX)

Head of Operations

2019 - PRESENT
Pulsar Fusion
  • Raised €325,000 from the UK Space Agency for nuclear-powered electric propulsion systems research. Pulsar's collaborators were Southampton University, Cambridge University, and Nuclear AMRC on October 2022.
  • Gathered €50,000 via the UK government's satellite applications catapult for Pulsar's academic collaboration program with Southampton University. This program validated the electric propulsion product line I developed at Pulsar.
  • Designed and fabricated two hall-effect thrusters and a lanthanum hexaboride (LaB6) hollow cathode.
  • Built a high vacuum testing lab at Pulsar's Milton Keynes workshop.
Technologies: JavaScript, Flask, SQL, Arduino, Pandas, Git, NumPy, Matplotlib, Python, React, C++, Jupyter, Electronics, Arduino IDE, Mypy, SciPy, CSS, APIs, Technical Consulting, Front-end Development, Python 3, Embedded C++, Technical Reports, Proof of Concept (POC), Architecture, CTO, Team Leadership

Software Developer

2018 - PRESENT
Openset Ventures
  • Designed, built, and developed a MOSFET control board plus the embedded control software for our in-house rocket system control board, using C++ and Arduino.
  • Created and developed a data analysis dashboard for rocket test firing data using Python, Jupyter, Matplotlib, Pandas, NumPy, and SciPy.
  • Built a data analysis dashboard for evaluating testing data from Pulsar Fusion's electric propulsion systems using Python, Jupyter, Matplotlib, Pandas, Numpy, and SciPy.
  • Constructed and designed a market research dashboard for visualizing the satellite spacecraft marketplace using Python, Pandas, Jupyter, Matplotlib, Altair, NumPy, and Qlik. The founders employed this dashboard to drive business strategy.
Technologies: C++, Arduino, HTML, CSS, Python 3, Pandas, Jupyter, Matplotlib, SciPy, NumPy, Python, Electronics, Arduino IDE, Technical Consulting, Embedded C++, Technical Reports, Git, Proof of Concept (POC), REST, Hardware, Architecture, Raspberry Pi, Internet of Things (IoT), User Interface (UI), User Experience (UX)

Hardware Consulting Expert for Game Rooms

2023 - 2023
  • Designed an immersive spy-themed game that was a huge 2x8m installation of targets, which responded to being hit with balls thrown by players and lit up.
  • Devised and prototyped the game, including the hit detection system. A major challenge was making individual targets sensitive enough to ensure weka hits were always registered while hard hits didn't trigger adjacent targets.
  • Tested the hardware and provided written and video results. This required ESP32 prototyping in C++.
  • Provided written instructions for installing and operating the product.
Technologies: Hardware, Architecture, Electronics, ESP32, C++, CAD, Proof of Concept (POC), Minimum Viable Product (MVP), Internet of Things (IoT)


2016 - 2020
Inspired Minds
  • Designed and developed an iOS cipher-breaking game. The game was part of the company's immersive escape-room-style educational offerings. The app was developed in Swift and SwiftUI and customized to run on iPadOS.
  • Created and developed an AppKit app to help students understand fractions, decimals, and percentages. This required a lot of UI work and user testing, the kids loved the app and their test scores increased by typically 20% on standardized testing.
  • Developed and designed a Python programming game environment that allowed students to learn the language by programming a Mars rover to explore the planet, looking for signs of life. Utilized Python, Jupyter, HTML, and CSS for the project.
Technologies: Swift, Python 3, HTML, CSS, SwiftUI, Objective-C, CTO, Team Leadership, CEO, UI Animation, User Interface (UI), User Experience (UX)

Control Software for Testing Rocket Systems

This Python, Flask, and React front end allows the user to issue commands to an Arduino microcontroller over a serial interface. The device state is stored in an SQL database.

This project aims to simplify the testing program of chemical and electric propulsion systems. The user may configure sub-systems in a dependency tree format, making accidental activation less likely. This also makes comparing different firings easier due to a common underlying control stack.

A delegate object handles control logic. This means the software can easily be reconfigured to operate different systems.

iOS Puzzle Solving Game

Puzzle Room is a Swift-UI-based iOS application that presents ciphers the user must solve. The application is presented in a vintage and retro color scheme with a pixel-art background.

Users are given a letter count to help them solve the code and can also ask for hints. This project grew out of one of my student's enthusiasm for these puzzles.

The story was written by my talented friend Tara Siddall. The Git repository also includes a Mac application called Puzzle Builder. This is a handy support application for generating JSON-formatted puzzles from raw text.

Arduino Control System

An Arduino project for reading commands from the serial interface and reliably activating and deactivating a series of MOSFET switches. With this project, reliability was vital, and the code implements a finite state machine to ensure that its behavior is well-defined.

iOS CoreMotion App: MagField

A SwiftUI app for measuring, logging, and exporting measurements of magnetic fields.

Our engineering team needed this app to validate the assembly of pulsar's products quickly. The app uses the Core Motion framework to access the magnetometer, where readings can be nullified to remove the device's magnetic field. The app uses the iOS native share sheet for sharing data in the CSV format.

Spy-themed Game

A sizeable physical game for a museum with a roughly 2x8m panel of circular targets which respond when hit by a ball. The targets light up to indicate the objective to the players.

I sketched out the game concept, constructed a hardware prototype, and subsequently brought the design to life in CAD.

The primary challenge was finding a suitable sensor technology that would give adequate sensitivity without letting strong hits trigger neighboring targets.

A secondary project involved designing a climbing ledge that could detect body weight, accommodate other LiDAR sensors, and remain safe for people to climb.

Integrating a remote team of six, I successfully delivered CAD illustrations, testing data, and installation guides for both installations.

Visual Note-taking App: Index Cards

This is a UIKit-based iPhone and iPad app for taking notes and marking them up using the Apple Pencil and text "stickers." The app is modeled on index cards students often use to prepare for exams. The cards are arranged in decks and can be added using the camera.

Machine Learning



NumPy, Matplotlib, Mypy, REST APIs, Pandas, SciPy, React, Node.js


Jupyter, Git, Figma, Xcode, CAD


Flask, SwiftUI, JSON Web Tokens (JWT), UIKit


Python, Swift, CSS, HTML, Python 3, Embedded C++, SQL, JavaScript, Octave, C++, Objective-C


Mobile Development, REST


Arduino, Mobile, iOS, MacOS, Raspberry Pi




Electronics, Arduino IDE, APIs, Technical Consulting, Technical Reports, Proof of Concept (POC), Embedded Systems, Microcontrollers, Hardware, Architecture, CTO, Team Leadership, CEO, Machine Learning, Logistic Regression, Front-end Development, Internet of Things (IoT), UI Animation, User Interface (UI), User Experience (UX), Artificial Neural Networks (ANN), CSV, Data Acquisition (DAQ), iPad, iOS Camera, ESP32, Minimum Viable Product (MVP)

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