Embedded & Prototyping Engineer
Posted on November 19, 2025 (24 minutes ago)
About Natural Cycles
Natural Cycles is a leading women27s health company that developed the world27s first birth control app, used by millions globally. They are a fast growing startup promoting an international working environment with smart and ambitious colleagues based in Stockholm, Geneva, New York, and remotely. Their mission is to pioneer women27s health through research and passion, empowering every woman with knowledge to take charge of her health.
Job Overview
We are looking for an engineer who loves building things end-to-end, lives in firmware but isn27t afraid to pick up a soldering iron, spin a test jig, or open Xcode to verify app integration.
You will work directly with the Head of Hardware to prototype, test, and refine the next generation of wearable devices, bridging firmware, hardware, and app layers. Fast idea generation and problem solving is encouraged.
This role allows working across the stack from firmware optimization to app development and data analysis, driven by curiosity and iteration.
Responsibilities
Firmware Development & Optimization
- Implement and improve sensor drivers, data collection, and low-power algorithms
- Maintain and improve BLE communication, background updates (FOTA), and data transfer
- Customize and structure raw logs for testing and analytics
- Debug firmware plugins and integrate analytics for data validation
- Profile and reduce battery consumption across operating modes
Hardware Prototyping & Validation
- Perform hardware modifications and assist in sensor integration or board validation
- Contribute to test setups for endurance, temperature, and performance validation
- Support design iterations (materials, ergonomics, assembly feedback)
- Participate in certification and compliance efforts
App & Tooling Collaboration
- Use code generation tools to develop, extend, or debug iOS and Android apps
- Prototype app-side visualizations
- Collaborate with software engineers to verify firmware to app data flows
- Contribute to automation and data validation pipelines when needed
Qualifications
- 3 to 5 years of experience and a strong background in embedded systems, firmware, or electrical engineering
- Proficiency in C/C++ and familiarity with ARM-based MCUs (e.g., nRF52, STM32, CC2642)
- Experience with BLE, sensor interfacing (IB2C/SPI), and low-power design
- Comfort with hardware tools (oscilloscope, soldering, basic rework, or prototype bring-up)
- Interest in using AI-assisted development tools (Cursor, Copilot, etc.) for firmware and app experiments
- A practical, experimental mindset with early testing, measuring, and iterating
Bonus Points
- Familiarity with data analysis and app analytics
- Experience with Swift (iOS), Kotlin (Android), or cross-platform frameworks like Ionic or React Native
- Exposure to temperature or optical sensing systems
- Understanding of wearable power management and BLE stack tuning
- Curiosity about digital health, female physiology, or biometric sensing
Why You27ll Love It Here
- Work directly with Natural Cycles27 Head of Hardware on wearable development
- Freedom to experiment from firmware to hardware to app-level
- Use modern tools and do real-world R26D with clear objectives and goals
- Be part of a small, deeply technical team where ideas move fast and impact is tangible
Location
The role is remote-friendly with a focus on collaboration with the Head of Hardware based in Stockholm, Sweden. Relocation support is offered for those not living in Sweden.
How to Apply
To apply, upload your CV and answer the questions on the application form on the career site. Applications via email are not accepted due to GDPR. Only applications in English submitted through the career site will be considered.
Natural Cycles values diversity and inclusion and welcomes candidates from all backgrounds, committed to creating an inclusive environment.
Note: They are not looking for consultants or recruitment agency help.
How to Apply
To apply, upload your CV and answer the questions on the application form on the career site. Applications via email are not accepted due to GDPR. Only applications in English submitted through the career site will be considered.
Natural Cycles values diversity and inclusion and welcomes candidates from all backgrounds, committed to creating an inclusive environment.
Note: They are not looking for consultants or recruitment agency help.