Hire Embedded C Developers — Firmware Development Company

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Hire Embedded C Developers — Firmware Development Company

You have hardware. You need firmware that ships on schedule, with clean architecture, and without hiring a full-time engineer for a project that ends.

CimpleO is a firmware development company that builds contract embedded C and firmware for hardware companies, IoT startups, and industrial automation teams. We’ve shipped: a 2.2-year-battery asset tracker (STM32L4 + GSM), a UHF RFID module (JRD-100), a LoRa-based smart metering network, and a portable ISP programmer for AVR and ESP32. Our engineers write firmware that runs in the field.

What We Build

IoT & Asset Tracking Firmware for GPS/GSM trackers, LoRa sensors, BLE beacons, and NB-IoT devices. Low-power architecture, OTA update support, reliable transmission under bad connectivity. Our IoT GAT tracker runs 2.2 years on a single 3.7V Li-Ion cell — achieved through peripheral power gating, RTC-based sleep scheduling, and transmission batching over GSM.

Industrial Automation & Control CAN bus, Modbus RTU/TCP, RS-485, and Profibus stacks. RTOS scheduling for time-critical control loops. Hard real-time where PLC replacement is the goal. MISRA C where process safety compliance is required.

Custom Modules & Hardware Products From bare-metal BSP bring-up to full application firmware on custom silicon. We built the JRD-100 UHF RFID module firmware from scratch — protocol stack, antenna tuning feedback loop, and host interface — and the A9G GPS/GSM development board firmware with full AT-command and NMEA parsing layers.

Smart Metering & LoRa Networks Multi-node LoRa mesh networks with cloud dashboards and automated meter reading for electricity, water, gas, and heating. See our IoT Home Smart Cloud project — 200+ nodes in a single deployment with sub-2% packet loss.

Safety-Critical & Certified Firmware IEC 61508 SIL-1/SIL-2 compliance, MISRA C:2012 static analysis, DO-178C familiarity for avionics-adjacent work. We run systematic testing (unit tests on-target and off-target with CMock/Unity), code coverage measurement, and deliver documentation packages for certification authorities.

Our Firmware Development Process

Week 1 — Technical Scoping We review your schematics, datasheets, communication specs, and power budget. You get a written assessment: architecture recommendations, risk flags, component concerns, timeline, and cost.

Weeks 2–4 — Architecture & BSP MCU bring-up: clock tree, linker script, startup, HAL layer. Peripheral drivers (GPIO, SPI, I2C, UART, ADC, DMA). Boot sequence, watchdog, fault handlers. Hardware-in-the-loop testing against your actual boards.

Weeks 4–N — Application Firmware Communication stacks, sensor fusion, RTOS task design, power management state machine, OTA update mechanism. You get running builds every week.

Final Phase — Hardening & Handover Load testing, soak testing, edge-case injection (power glitches, bus errors, network loss). Documentation: architecture overview, peripheral register map, build/flash instructions. Source code in your repository with full history.

Engagement Models

Fixed-Scope Project Defined deliverables, agreed timeline, fixed price. Right for greenfield firmware with clear requirements. We scope upfront so every change is explicit.

Dedicated Embedded Engineer Monthly retainer, embedded in your Jira/Linear workflow. Right for product companies with ongoing firmware needs — new hardware revisions, feature additions, bug investigation, supplier support. No recruiter fees, no 3-month ramp-up.

Code Audit & Rescue Existing firmware with reliability, power, or performance issues. We audit the codebase, instrument the system, identify root causes, and deliver a prioritised fix plan with implementation if needed.

When to Hire vs In-House

Hire a full-time embedded engineer when your product roadmap depends on continuous firmware work across multiple products and the firmware is your core IP. Use contract development when:

You need specific expertise (LoRaWAN, CAN, MISRA C) for one project cycle.
Firmware is a one-time deliverable, not a long-term asset.
You need to ship fast and can’t wait 3–4 months for a qualified hire to ramp up.
You want senior expertise without senior salary overhead.

Most of our clients are hardware startups and mid-size industrial companies that keep a small in-house team for long-term maintenance and use us — as their firmware development agency — for new product development sprints.

Technical Stack

MCUs: ARM Cortex-M (STM32 full line, NXP Kinetis/LPC), ESP32/ESP8266, AVR (ATmega/ATtiny/XMEGA), PIC32
RTOS: FreeRTOS, Zephyr, ThreadX; bare-metal scheduler design when RTOS overhead isn’t justified
Protocols: I2C, SPI, UART, USB (CDC/HID/MSC), CAN 2.0A/B, Modbus RTU/TCP, BLE 5.x, LoRaWAN 1.0.x/1.1, Zigbee, GSM/GPRS/LTE-M, NB-IoT, MQTT, CoAP
Toolchains: GCC ARM Embedded, Keil MDK, IAR EWARM, ESP-IDF, PlatformIO
Debug: J-Link, ST-Link, OpenOCD, SEGGER SystemView, logic analyzers, protocol decoders
Quality: MISRA C:2012, PC-lint, Cppcheck, Unity/CMock for unit tests, LCOV coverage

For firmware paired with a cloud backend, mobile app, or PCB design, see our IoT Engineering service. For a dedicated IoT engineer covering both firmware and connectivity layers, see IoT Engineer for hire.

Get a Firmware Estimate

Tell us your MCU, connectivity requirements, timeline, and production volume target. We’ll respond within 24 hours with a scope assessment.

Frequently Asked Questions

How much does custom firmware development cost?

Fixed-scope firmware projects run $5,000–$30,000 depending on MCU complexity, peripheral count, communication stacks, and certification requirements. Dedicated embedded engineer retainers start at $8,000/month. After a 1-week technical scoping, we give you a number.

What is the difference between embedded C and embedded C++?

Embedded C is a lean subset of C99/C11 — no dynamic memory, no exceptions, deterministic stack usage. Embedded C++ adds classes and templates but requires careful discipline (no STL, no RTTI, no exceptions by default) to stay deterministic. We use both: bare-metal BSP and drivers in C, application layers in C++ when the project calls for it.

Do you handle MCU bring-up from scratch?

Yes. Bare-metal BSP bring-up — clock tree, memory map, linker script, startup code, peripheral init — is a core part of what we do. We've brought up STM32, ESP32, NXP Kinetis, and custom RISC-V targets from blank silicon.

Can you work with our existing hardware design?

Yes. Send us schematics and datasheets under NDA and we'll review your design before starting. We've rescued several projects where firmware was blocked by hardware issues — we flag them early rather than code around them.

How long does a typical firmware project take?

A focused peripheral driver or communication stack: 2–4 weeks. A complete firmware for a mid-complexity IoT device (sensors, connectivity, OTA, power management): 8–16 weeks. Full product firmware from bring-up to certification-ready: 4–6 months. If boards are still in fab, we start on simulators or evaluation kits.

Do you sign NDAs before reviewing schematics?

Always. We sign mutual NDAs before any technical discussion involving your IP. We never share client project details publicly without explicit permission — the case studies on this site are all client-approved.

What MCU families do you support?

ARM Cortex-M (STM32 full line, NXP Kinetis/LPC, SAM), Xtensa (ESP32/ESP8266), AVR (ATmega, ATtiny, XMEGA), PIC32, and selected RISC-V targets. For new projects we default to STM32 or ESP32 based on connectivity and power requirements.

Can I outsource embedded firmware development to CimpleO?

Yes. We work as an external firmware development partner for hardware companies, IoT startups, and industrial teams that don't want to hire a full-time embedded engineer. You get a senior engineer's output under NDA, with full source code ownership. Most clients treat us as their firmware development team for the duration of a product cycle.

Why use a firmware development company instead of a freelancer?

A freelancer is one person. If they're sick, overloaded, or quit mid-project, your hardware sits idle. A firmware development agency brings a team — so your project has backup coverage, peer review, and structured handoff documentation. We've taken over firmware from freelancers a dozen times; the main issues we fix are incomplete documentation, no version control, and no test coverage. We deliver none of those problems.