Kacper Kowalski
Senior Embedded Software Engineer / Lead Contributor Freelance / B2B / Self‑employed
C/C++ • Modern C++ • Embedded Systems • Firmware • IoT & Connectivity • MCU & Embedded Linux • 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 wireless and cloud-connected IoT firmware, and CI/CD pipelines for embedded hardware testing. Comfortable working across resource‑constrained microcontrollers and Embedded Linux systems, with additional experience in safety‑critical and radio/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
- Worked within the Yocto-based build environment for the embedded Linux image — building, flashing, and occasional recipe adjustments
- Built CI pipelines and static analysis tooling
Technologies: C, C++20, FreeRTOS, ARM Cortex‑M4 (LPC51U68), Python, Bash, CMake, Ninja, Yocto, 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: TDD, Unity, Catch2, Google Test, Robot Framework
- CI/CD: GitHub Actions, GitLab CI, Docker
- Debugging: GDB, OpenOCD
Availability
Open to freelance contracts and long‑term consulting engagements requiring strong ownership and system‑level thinking.