Antonio Stepien, Developer in Christchurch, Canterbury, New Zealand
Antonio is available for hire
Hire Antonio

Antonio Stepien

Verified Expert  in Engineering

Embedded Software Engineer and Developer

Christchurch, Canterbury, New Zealand
Toptal Member Since
November 3, 2020

With 20 years in software engineering, Antonio has developed a diverse skill set spanning software development, DevOps, and back-end technologies in the automotive, avionics, and defense sectors. His expertise extends beyond embedded systems to CI/CD pipelines and back-end architectures. As a team leader, he excels in high-performance team orchestration, SDLC, and V-model methodologies. Antonio is dedicated to delivering quality projects, making him a valuable asset to any team.


Alberta Ltd
Architecture, Web Development, Mobile Development, Solution Architecture
Energy, Front-end, Back-end, Embedded C, Systems, Angular
Enphase Energy
Certifications, DevOps, C, Embedded C, CI/CD Pipelines, Orchestration, Linux




Preferred Environment

Python, C, Linux, AWS CLI, ARM Linux, Arm Cortex-M4, Functional Safety, GitOps, DevOps Engineer

The most amazing...

...project I've developed is an advanced cybersecurity system for IoT devices that greatly improved data protection and operational efficiency across industries.

Work Experience

Senior Architect

2024 - 2024
Alberta Ltd
  • Designed a compliant system architecture, created an offline-capable solution, and worked on a user-centric platform. I also advised on tech stack, ensuring scalability and security and enhancing operational efficiency and compliance.
  • Used collaborative methodology to deliver the architecture design product.
  • Oversaw launch processes, collaborating on a user-centric platform and advising on tech stack, ensuring scalability and security, which enhanced operational efficiency and compliance for multiple businesses.
Technologies: Architecture, Web Development, Mobile Development, Solution Architecture

Software Development Team Leader

2023 - 2024
  • Enhanced development workflow by integrating CI/CD pipelines, reducing build times and deployment errors by 25%.
  • Boosted team productivity by implementing Agile methodologies, improving on-time project delivery by 30%.
  • Improved system reliability by leading the development of robust diagnostic tools, increasing software stability and reliability by 20%.
Technologies: Energy, Front-end, Back-end, Embedded C, Systems, Angular

Team Leader, Senior Software and DevOps

2021 - 2024
Enphase Energy
  • Developed automated testing frameworks, reducing QA time. Implemented CI/CD pipelines. Led a team to enhance system security, resulting in zero breaches over 12 months.
  • Tracked and fixed bugs, managed releases across multiple geolocations, and ensured certification compliance.
  • Oversaw the entire process and trained developers in cutting-edge methodologies and methods for embedded development.
Technologies: Certifications, DevOps, C, Embedded C, CI/CD Pipelines, Orchestration, Linux

Functional Safety Engineer

2023 - 2023
  • Designed and implemented a comprehensive cybersecurity system for automotive safety, enhancing vehicle data protection and compliance with ISO 26262.
  • Utilized Azure DevOps for CI/CD pipeline management, significantly reducing deployment times and increasing system reliability.
  • Developed and executed quality assurance protocols, improving system robustness and achieving a 95% success rate in safety audits.
Technologies: Functional Safety, ISO 26262, Cybersecurity, Automotive, IT Security, Quality Assurance (QA), Security

Embedded C++ Developer

2021 - 2022
Toyota Material Handling, Inc - Main
  • Collaborated with the architecture team leader to manage three teams responsible for the architecture documentation and development. Also accountable for integration team of two members.
  • Managed the document review process, code review, Ci/CD, and integration process using Azure DevOps.
  • Reached documentation integration, design review, and validation in eight months of work, allowing Toyota Material Handling to have clear visibility of the business and system requirements versus implementation.
Technologies: Embedded C++, C++, Internet of Things (IoT), CANopen, CAN Bus, Embedded Software, C

Senior Software Embedded Engineer (Remote Role)

2019 - 2022
  • Developed the system control unit using soft-device from nRF52 of Nordic and ANT+ framework.
  • Created the library and drivers for the implementation of the different sensors, CAN, pressure sensor, battery management systems, and gyroscope.
  • Developed the Manta5 app for the initial 300 users for the first hydrofoil bike.
Technologies: I2C, Serial Peripheral Interface (SPI), Universal Asynchronous Receiver/Transmitter (UART), Accelerometers, GPS, Bluetooth Low Energy (LE), Device Firmware Updates (DFU), Bitbucket API, Docker, Bitbucket, Nordic nRF52, Bluetooth, DevOps, Embedded C, Embedded Software, C

Senior Software Engineer

2018 - 2021
MAS Zengrange
  • Developed the entire CI/CD environment for the legacy and new development process. Used open-source tools such as Jenkins, GitLab, Docker, and enterprise tools like LDRA.
  • Created a new ballistic and fire system control for regimental applications using rugged laptops.
  • Implemented a full development process for enterprise-level operations without any external dependencies because the company maintains the entire system locally.
Technologies: Cortex-M Microcontrollers, Arm Cortex-M0, GNU Toolchain, MISRA Compliance, IEC 61508, C++, Embedded C, Linux, Jenkins, Ruby, Python, DevOps, Safety-critical, Embedded Software, C

Software Integration Engineer

2018 - 2018
Martin JetPack
  • Developed and integrated a few systems during my short time. For example, I tailored all old databases saved in CSV files to MongoDB.
  • Fixed a few bugs in the flight data recorder system. It was developed using embedded software in a Cypress microcontroller PSoC 5LP Cortex-M3.
  • Added a bootloader to the Flight Data Recorder and improved the download speed via USB from 40 to 8 minutes.
Technologies: C#, Python, Embedded C, MongoDB, Databases, Embedded Software, C

Senior Software Engineer

2016 - 2018
Link ECU Management
  • Moved Link ECU products to a brand new platform because the main microcontroller was obsolete.
  • Used reusable programming based on commonalities of the current and new features of the system. I implemented the set up for all compilers, debuggers, trace, and IDES for these new technologies.
  • Trained the previous team about the technologies and coding using the MISRA C rules for the defense coding approach. It solved the problems related to bad practices in the previous products.
Technologies: Real-time Operating System (RTOS), Arm Cortex-M4, AUTOSAR, MISRA Compliance, C#, Embedded C, Git, Embedded Software, C

Embedded Engineer - Contractor

2014 - 2016
  • Developed firmware for architecture ARM Cortex-M0/M3 microcontrollers and PIC18F. Also uCLinux development for Gateway using Wifi and Bluetooth. These products were the beginning of the HomeAutomation product family,.
  • Implemented SVN server and subversion system training for the team because they had not any supervision system in place before.
  • Helped the R&D team to move from a simple product to a new and sustainable product development process.
Technologies: Bluetooth, WiFi, uClinux, Linux, Embedded C, Embedded Software, C

Project Manager

2014 - 2016
  • Managed a team of five developers for supporting all products from database servers and electronics product production/development.
  • Reduced the production cost by rearranging the product portfolio. It turned the production management more efficient and improved the roadmap for the new products.
  • Used Agile methodologies to improve the deliverables from the R&D team and reducing the project's timelines.
Technologies: ARM Architecture, File Systems, USB, RFID, Industrial Internet of Things (IIoT), M2M, Ethernet, Key Performance Indicators (KPIs), Embedded C, C#, Project Management, Embedded Software, C

Embedded Engineer

2013 - 2014
Creare Systems
  • Developed the prototype for a new body computer using Linux Embedded in a platform Cortex-A8, Cortex-M4 for sensors, GSM, and GPS technologies. This prototype was phase one for the new product generation.
  • Learned the entire Linux toolchain. Built and developed process for Linux Embedded within three months.
  • Delivered the project on time for the next stage for testing. The time frame for this project was 14 months.
Technologies: GNU Toolchain, Linux Device Driver, Linux, Embedded C, Embedded Software

Developer Engineer

2009 - 2013
  • Developed communication and interface between the user and ECUs via USB, wireless, ethernet, CAN (controller area network). Also created products using micro-controllers 8/16/24/32bits. It is in several architectures as RISC, MIPS, ARM, and PowerPC.
  • Created a testing rig for an automated test using a microcontroller for the automation of ECUs.
  • Developed bootloader firmware for all products in each specific embedded platform.
Technologies: Arm Cortex-M3, C#, Bootloaders, Intel MCS-51 (8051), Microchip PIC18, PIC32, PIC16, Embedded C, Embedded Software, C

Embedded System Developer

2007 - 2009
Actia of Brazil
  • Reverse engineered automotive electronics modules and developed the test processes within the ISO TS16949:2002.
  • Simulated ECU using Vector CANalizer for automated tests.
  • Created documentation for users and training for retailers.
Technologies: Automotive, Communication, Reverse Engineering, Embedded C, C++, Embedded Software, C


The FT350 is a FuelTech engine monitoring and control system: electronic injection, integrated instrument panel, data acquisition, and power management. It is a multi-use ECU for motorsport, drift, and drag racing cars.

USB-CAN Converter
USB-CAN converter used with the FT line modules (FT200, FT250, FT300, FT350, and FT400) for updating and communicating with the computer (map editing, backup). This device used two C8051 of Silabs semiconductors to create a robust solution for an automotive environment.

Hydrofoil Bike

The world's first hydrofoil bike that replicates the cycling experience on the water. I developed the entire firmware for the system control unit to manage sensors, electric motors, and the battery management of the system.

ECU project, but with added Onboard Digital Wideband Lambda Control. The G4X platform features a faster processor, faster communications, and 512 megabytes of data logging—a Power Architecture microcontroller production based on legacy product features. Since the legacy platform would not use the old microcontroller, I joined the team with my previous Power Architecture microcontroller expertise.
2014 - 2016

Master's Degree in Project Management

Unisinos University - São Leopoldo, Brazil

2006 - 2011

Bachelor's Degree in Electrical Engineering

Pontifical Catholic University of Rio Grande do Sul (PUCRS) - Porto Alegre, Brazil


OpenCV, Altium, Bitbucket API, Accelerometers


CMake, Subversion (SVN), Shell, Eclipse IDE, MATLAB, Jenkins, GNU Toolchain, Bitbucket, Git, Arm Cortex-M4, Arm Cortex-M3, AWS CLI


Linux, ARM Linux, Ubuntu Linux, Windows, Android, iOS, Docker, Bluetooth Low Energy (LE), Amazon Web Services (AWS)


Google Test, Flutter, Angular


C, Embedded C++, Go, C++11, Python, Ruby, Embedded C, Python 3, C#, C++


Databases, MongoDB


Defensive Programming, DevOps, Mobile Development

Industry Expertise

Automotive, Telecommunications, Project Management, Cybersecurity


Embedded Systems, Firmware, Embedded Software, Leadership, DevOps Engineer, Networking, USB, AUTOSAR, ISO 26262, Real-time Operating System (RTOS), MISRA Compliance, WiFi, Military, Scripting, Software, Electronics, DSP, Reverse Engineering, Renewable Energy, Physics, Wireless Protocols, Projects, Product Delivery, Post-production, Safety-critical, IEC 61508, DO-178B/C, Industrial Internet of Things (IIoT), IoT Protocols, Aerospace & Defense, Automotive Controller Area Network (CAN), Intel MCS-51 (8051), Bluetooth, Nordic nRF52, Key Performance Indicators (KPIs), Ethernet, M2M, RFID, File Systems, ARM Architecture, uClinux, Linux Device Driver, PIC16, PIC32, Microchip PIC18, Bootloaders, Communication, Device Firmware Updates (DFU), GPS, Universal Asynchronous Receiver/Transmitter (UART), Serial Peripheral Interface (SPI), I2C, Arm Cortex-M0, Cortex-M Microcontrollers, Internet of Things (IoT), CANopen, CAN Bus, Architecture, Web Development, Solution Architecture, Functional Safety, GitOps, IT Security, Quality Assurance (QA), Security, Certifications, CI/CD Pipelines, Orchestration, Energy, Front-end, Back-end, Systems

Collaboration That Works

How to Work with Toptal

Toptal matches you directly with global industry experts from our network in hours—not weeks or months.


Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.

Start your risk-free talent trial

Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.

Top talent is in high demand.

Start hiring