Kacper Kowalski
Senior Embedded Software Engineer / Lead Contributor Freelance / B2B / Self‑employed
C/C++ • Modern C++ • Embedded Systems • Firmware • MCU & Embedded Linux • IoT • Safety-Critical (SIL) • Build Systems • CMake • Toolchains • CI/CD • RTOS • Audio • Testing • Python • OSS
Profile
Senior embedded software engineer with deep expertise in modern C++, CMake‑based build systems, RTOS architectures, and MCU firmware development. Proven track record delivering complex freelance projects end‑to‑end: from low‑level drivers and object‑oriented firmware design to CI/CD pipelines for embedded hardware testing. Comfortable working across resource‑constrained microcontrollers and Embedded Linux systems, with additional experience in safety‑critical systems and radio and video pipelines. Strong focus on correctness, maintainability, and clean architecture.
Freelance Experience (Commercial)
Senior Embedded Software Engineer – Freelance (B2B)
Self‑employed | Dec 2021 – Present
Primary long‑term consulting partner: HalReady GmbH (2023 – present), a German company delivering industrial safety and sensing solutions. Engaged across multiple customer projects as a senior embedded engineer, including safety‑critical human detection systems, industrial robotics, container monitoring devices, and embedded video platforms. Additional direct freelance contracts alongside.
Lead Embedded Software Developer – SIL2 Safe Human Detection System
Jan 2025 – Mar 2026
- Drove embedded firmware architecture and development for a multi‑platform SIL2 safety‑critical human detection system combining mmWave radar, thermal imaging and human detection algorithm
- Designed and implemented modular CMake‑based build infrastructure with cross‑compilation toolchains for multiple MCU targets
- Established unified embedded testing infrastructure, integrating Unity for device‑side tests and Catch2 for host‑side testing
- Spearheaded development of safety‑critical communication modules (OSSD, FSI, RS485 ring protocol)
- Ported firmware across evaluation boards and production hardware while maintaining backward compatibility
- Acted as primary code reviewer, maintaining code quality and guiding architectural decisions across the team
- Coordinated with hardware teams on platform bring-up, sensor integration, and interface definitions
- Onboarded new team members to the codebase, architecture, and development workflow
- Took ownership of TI AM64x platform bring‑up, including DDR memory integration
- Architected the Main State Machine (MSM)
Technologies: C++17, C, Python, FreeRTOS, CMake, ARM Cortex‑R5F, AM64x, AM263Px, IWR6843, TI MCU+ SDK, TI mmWave SDK, TI SysConfig, Unity, Catch2, Nanopb, Protocol Buffers (Protobuf), OpenCV, UART, SPI, FSI, RS485, Git, Docker
Senior C++ / Build Systems Engineer – Build & Toolchain Optimization
for Autokroma | Jan 2024 – Oct 2024
- Optimized a large‑scale C++ / CMake build system, focusing on reducing compilation times
- Refactored and modernized CMake configuration using target‑based design and improved dependency hygiene
- Identified and eliminated build bottlenecks across local and CI environments
- Integrated and analyzed build performance using ccache, vcperf, and pytracing
- Improved developer productivity and CI turnaround times for a complex, multi‑module codebase
Technologies: C++, CMake, Ninja, ccache, vcperf, pytracing, Windows, CI/CD
Sensorsuite – Container Monitoring Device (CMD)
IoT Firmware Engineer | Jan 2024 – Apr 2024
- Developed IoT firmware for industrial container monitoring devices
- Implemented multi‑connectivity support: LoRaWAN, satellite, Wi‑Fi
- Integrated sensors: GNSS, IMU, temperature, NFC/RFID
- Implemented CAN bus telemetry
- Designed FreeRTOS‑based real‑time architecture
- Built CI/CD pipelines using GitHub Actions and Docker
Technologies: C++20, ESP32, FreeRTOS, PlatformIO, LoRaWAN, Satellite Communication, CAN Bus, GNSS/GPS, NFC/RFID, JSON, Docker, GitHub Actions, Git
Embedded Video Encoding Pipeline (Confidential Camera Systems)
Embedded Linux / Video Engineer | Aug 2023 – Oct 2023
- Worked on an embedded video encoding pipeline for professional cinema camera systems
- Implemented RTSP video streaming using Live555
- Integrated H.265/HEVC hardware encoding via Xilinx VCU
- Implemented SDI video input capture
- Worked on RAW video recording using memory‑mapped buffers (mmap)
- Low‑level handling of video formats (YUV/RGB)
Technologies: C++, CMake, Xilinx VCU, H.265/HEVC, Live555, RTSP, SDI, OpenSSL, mmap, Allegro encoder, Embedded Linux
Industrial Cleaning Robot
Embedded Software Engineer – Robotics | May 2023 – Jul 2023
- Optimized power consumption and motor control algorithms
- Developed PID motor controller and low‑level device drivers
- Modernized legacy codebase to C++20
- Built CI pipelines and static analysis tooling
Technologies: C, C++20, FreeRTOS, ARM Cortex‑M4 (LPC51U68), Python, Bash, CMake, Ninja, Docker, GitLab CI, SonarQube, Google Test, Bluetooth (BlueZ)
Barcode / QR Event Registration Device
Embedded Firmware Engineer – Freelance | May 2022 – Oct 2022
- Designed and implemented full device firmware in C++20 on ARM Cortex‑M4 (SAM4S)
- Built FreeRTOS‑based architecture with LTE‑M connectivity
- Integrated cloud communication using MQTT, LwM2M/CoAP, TLS
- Implemented drivers for NFC (TRF7970A), barcode scanner, proximity sensors, battery fuel gauge
- Developed secure bootloader and OTA update mechanism
Technologies: C++20, C11, FreeRTOS, ARM Cortex‑M4, CMake, ARM GNU Toolchain, LTE‑M (u‑blox SARA‑R422S), MQTT, TLS/SSL, I2C, SPI, UART, USB CDC, OpenOCD, GDB, Unity, Catch2
OpenCV on Microcontroller
Embedded C++ Engineer – Freelance | May 2022
- Ported and adapted selected OpenCV algorithms for a resource‑constrained MCU
- Target platform: STM32U575 (ARM Cortex‑M)
- Focused on memory usage, performance, and build system integration
Technologies: C++17, OpenCV, STM32Cube, ARM Cortex‑M, CMake
Epaper Label Shop System
Embedded Firmware Engineer – Freelance (for Info Technologies / NAOS Software) | Apr 2021 – Sep 2021
- Designed and implemented a full end-to-end system: a central Embedded Linux Gateway (Raspberry Pi) managing a fleet of BLE-controlled Epaper Label display devices in a one-to-many topology
- Gateway bridges the label fleet to the cloud via MQTT; each label (nRF52840, bare-metal) supports full remote display content control over BLE
Technologies: C++17, Bare‑metal, CMake, BLE, nRF52840, Python3, Raspberry Pi, MQTT
Open‑source & Independent R&D
Seqnaut and Sycosm (WIP) – Embedded Audio DSP & Synthesis Platform
Author | Mar 2026 – May 2026
- Designed a platform-portable embedded audio DSP framework for building any type of audio device — synthesizers, effects processors, drum machines
- Implemented a modular audio graph with topological sorting, RAII connection handles, and block-based float signal processing
- Built sequencing infrastructure: PianoRoll (event-based), StepGrid (step sequencer)
- Developed an 8-voice polyphonic synth engine with CLI and OSC control
- Designed and implemented a Transient Detector — dual-envelope adaptive threshold algorithm for detecting guitar attack transients (used for ambience ducking)
- Designed an Analog Front-End (AFE) to tap audio from BOSS GX-100 into Teensy Audio Shield; explored MIDI FX integration using GX-100 MIDI implementation
- Built host-side testing tools (PortAudio live input, WAV I/O, terminal oscilloscope) for algorithm validation before hardware deployment
Technologies: C++23, C, Python, CMake, FreeRTOS, Teensy 4.1 (ARM Cortex‑M7), Teensy Audio (Stoffregen), DaisySP, I2S/SAI, OSC, MIDI
Portable Bitfields
Author & Maintainer | Mar 2023 – Present
- Major development of a modern C++ bitfield abstraction library
- Focus on correctness, portability, and compile‑time guarantees
- Ongoing maintenance and community contributions
Jeff – Jungles Guitar Effect
Author | Dec 2020 – Mar 2021
- DSP audio project – a guitar effect pedal
- Real‑time audio processing on embedded hardware
- Built a full CMake‑based test automation system to verify signal levels, SNRs, and output signal characteristics (e.g. distortion effect shape validation)
Technologies: C++20, FreeRTOS, CMake, DSP, ADC, DAC, Analogue and digital electronics, test rigs, test automation
Aura Weather Station System
Co‑author | 2018 – 2020
- Side‑project for precision agriculture weather monitoring
- Developed with friends
Technologies: C++20, FreeRTOS, CMake, NB‑IoT, CoAP, Python3, STM32L4, Test rigs
LLVM / clangd Contributions
Open‑source Contributor | Oct 2023 – Nov 2023
- Contributed improvements to clangd, focusing on Code Actions for C and C++
- Worked with LLVM/Clang internals and libclang APIs
Tsepepe & TsepepeVim
Author – LLVM‑based Refactoring Toolset | Oct 2023 – Nov 2023
- Designed and implemented Tsepepe, a C++ refactoring tool built on LLVM/libclang
- Automated function definition generation and header/source pairing
- Implemented interface implementation scaffolding
- Created TsepepeVim, a Vim plugin acting as a frontend for Tsepepe
LlvmCrossCompileArmCortexM
Author & Maintainer | Nov 2021 – Present
- Cross‑compiled LLVM libraries (compiler‑rt, libc++, libc++abi, libunwind) for ARM Cortex‑M baremetal targets
- Provided pre‑built packages for multiple architectures (Cortex‑M0/M0+/M3/M4/M7/M23/M33/M55)
- Built with and without exception support, multiple floating‑point configurations
- Alternative to ARM GNU Toolchain for LLVM‑based embedded development
Technologies: CMake, LLVM, Clang, ARM Cortex‑M, Newlib, Cross‑compilation
JunglesOsHelpers
Author & Maintainer | Mar 2020 – Present
- RTOS helpers library with FreeRTOS, generic, and native implementations
- Reusable abstractions for embedded real‑time systems
- CMake‑based integration via FetchContent
Technologies: C++, FreeRTOS, CMake
Zynthian (Embedded Audio R&D)
Embedded Linux / Audio Exploration | Oct 2023 – Nov 2023
- Set up and configured Zynthian synthesizer on Raspberry Pi 3
- Explored embedded audio pipelines, MIDI, and Linux‑based music systems
Prior Employment (Employee Roles)
Embedded Software Developer – Mittemitte GmbH
Berlin, Germany | Jul 2021 – Oct 2021
- Maintained and developed firmware for Mitte Home Water Dispenser
Technologies: C, Make, Qualcomm QCA4020, AWS IoT SDK
Embedded Software Developer – HUM Systems GmbH
Berlin, Germany | Sep 2020 – Mar 2021
- Developed firmware for Livy Protect Smart Ring – a comprehensive solution for burglary protection, fire detection, air quality detection, and air conditions measurement
Technologies: ESP32, C++17, FreeRTOS, ESP‑IDF, CMake, MQTT, HTTP, TCP, TLS, Python3
Software Design Engineer – Etteplan Poland
Delegated to Kapsch Trafficom | Aug 2019 – Sep 2020
- Aug 2019 – Feb 2020: On‑site in Jönköping, Sweden
- Feb 2020 – Apr 2020: Remote from Poznan
- Wrote firmware for On‑Board Units for DSRC and GNSS Electronic Toll Collection, in a Scrum Team
- Wrote manual test cases, developed and maintained the build ecosystem for the project
Technologies: C++14, CoAP, DTLS, LwM2M, FreeRTOS, Python3, GitLab CI/CD, Docker, Robot Framework, CMake, Jira
IoT Engineer – Lerta
Poznan, Poland | May 2018 – Jul 2019
- Wrote firmware and managed build systems for bare‑metal devices:
- Thermostat controlled through ZigBee (nRF52840)
- Smart meters with STM32L4, controlled through NB‑IoT
- Wrote services for Linux Embedded based Smart Home Gateway
- Improved electronic design of low‑power devices, fixed hardware bugs
Technologies: C++17, C, FreeRTOS, NB‑IoT, ZigBee, CoAP, MQTT, HTTP, CMake, Make, Bash, Buildroot, Jenkins, Docker
Junior Embedded Developer – Novamedia Innovision
Poznan, Poland | Dec 2016 – May 2018
- Programmed firmware for an intercom with STM32F4
- Developed service for Linux Embedded to manage the intercom system
- Maintained and deployed firmware for a fleet of gateways and routers
Technologies: C, FreeRTOS, VoIP, PoE, MQTT, HTTP, CMake, Buildroot, C++14, Bash
Radiocommunication Assistant → Specialist – TELE‑COM
Poznan, Poland | Jun 2015 – Nov 2016
- Radiocommunication support and technical operations
Technical Skills
- Languages: C, C++, Python, Bash
- Safety‑critical: SIL2, OSSD, deterministic state machines
- Embedded: FreeRTOS, Bare-metal, ESP-IDF, Embedded Linux, Yocto, Buildroot
- Build Systems: CMake, Ninja, Make, PlatformIO
- Toolchains: ARM GNU Toolchain, LLVM/Clang
- Protocols: MQTT, CoAP, LwM2M, RTSP, TLS, DTLS, CAN, FSI, RS485, I2C, SPI, UART, USB, NFC
- Wireless: BLE, LoRaWAN, NB‑IoT, LTE‑M, ZigBee
- Audio / DSP: I2S/SAI, MIDI, OSC
- Testing: Unity, Catch2, Google Test, Robot Framework
- CI/CD: GitHub Actions, GitLab CI, Docker
- Debugging: GDB, OpenOCD
Availability
Open to freelance contracts, long‑term consulting, and safety‑critical embedded systems projects requiring strong ownership and system‑level thinking.