For inventors and first-time founders
Embedded firmware development that makes your invention behave, last and update without a single brick
Firmware is the code inside your product's chip. It decides what happens when someone presses a button, how long the battery lasts and whether an update arrives safely. We write it, test it on real boards and hand you every file and key. Under NDA, by a US team.
- NDA from first contact
- US team in Toledo, Ohio
- You own the code and keys
The short answer
What is embedded firmware?
Embedded firmware is the code stored on the chip inside your product. It reads the sensors, runs the buttons and lights, talks to the phone or Wi-Fi, and decides when the device sleeps to save battery. Unlike app software, it ships inside the hardware, so it has to work first time and update safely once customers own it.
Software runs on phones and computers that are easy to update. Firmware runs on one specific chip, with tiny memory and a battery to protect, so a mistake can stop the whole product.
Moment 01 of 05
Button pressed
The chip wakes, reacts in milliseconds and goes back to sleep.
Moment 02 of 05
Sleeping
Nearly everything is switched off so the battery can last for months.
Moment 03 of 05
Battery low
The device warns the user and saves its data before it shuts down.
Moment 04 of 05
Wi-Fi drops
It keeps working offline and reconnects by itself when Wi-Fi returns.
Moment 05 of 05
Update arrives
The new version installs beside the old one and switches only if it works.
Sound familiar?
Six signs your product needs firmware help now
Code stuck at 30%
A freelancer started it, went quiet and left code nobody else can finish.
Works on the desk
It runs fine on your bench, then fails in customers' homes and networks.
Battery dies in days
The datasheet promised months. Real units go flat long before that.
Factory wants a file
The factory asks for programming files and test steps you never got.
Your chip is gone
The chip is out of stock and the code can't move to a different one.
Updates scare you
You're afraid to update, because one bad file could stop every unit.
What we build
Embedded firmware development, from first line to factory
One team writes, tests and documents the code your product runs on, then supports it after launch.
Chip choice
The right chip for your battery, radio, budget and supply.
Drivers and sensors
Every sensor, motor, screen and button read and driven reliably.
Product behavior
The rules your product follows, agreed in writing before any code.
Low power
Sleep, wake and radio timing tuned so the battery lasts.
Wireless
Bluetooth, Wi-Fi, Thread or LTE-M that reconnects on its own.
Safe updates
A bootloader and signed updates that roll back if anything fails.
Security
Unique passwords, secure boot and locked debug ports from day one.
Factory firmware
Programming files and self-tests so the factory checks every unit.
Code rescue
We review inherited code, keep what works and fix what doesn't.
Need the circuit board? PCB design. The app and cloud? IoT product design. On-device AI? Physical AI. The lab tests? Certification and compliance.
Already have an Arduino or ESP32 prototype? We keep what works and turn it into production firmware.
Over-the-air updates
Updates that can never brick your product
A bricked device stops working after a bad update and can't be fixed by its owner. In 2017 one automatic update bricked more than 500 smart locks at a single company. We build every product so that can't happen to yours.
- 01Download to a spare slotThe new version lands beside the old one, which stays untouched.
- 02Check the signatureThe device accepts only files signed with your key, so fakes can't install.
- 03Switch and testIt starts the new version once and checks that everything works.
- 04Roll back on failureIf anything fails or the power cuts out, it restarts on the old version.
Then we release in stages: a small group first, everyone else once their units report back clean. Done right, an update can even replace a recall visit: a 2025 recall covering 239,382 cars was fixed over the air.
What you own
The handover box: everything you own, from day one
If your developer disappeared tomorrow, could someone else rebuild and ship your firmware? With us the answer is always yes.
- Source codeIn your own repository from day one, not ours.
- Build instructionsThe tools and steps to rebuild the exact same file.
- Signing keysThe keys that sign your updates, held by you.
- Factory filesProgramming files and test steps for the line.
- Update accountThe update server account, set up in your name.
- Architecture notesHow the code is organized, so anyone can continue.
- Test reportsWhat we tested, on which boards, with results.
- IP assignmentA written transfer of all rights in the code.
We sign an NDA before you share details, and you are never locked in to us.
Battery life
Battery life, planned before the board is built
Battery life is a budget, not a hope. It comes down to one sum: battery capacity divided by the average current your product draws. Firmware sets most of that average by deciding when the device sleeps, wakes and uses its radio.
Illustrative estimate, not a guarantee. We measure real boards before we promise a number.
- Asleep at 2 µAA coin cell could last about 11 years, so the battery's shelf life becomes the limit.
- One 1 mA leakA forgotten indicator LED can drain the same coin cell in about 8 days.
- Datasheet vs real boardOwners of popular ESP32 test boards measured 300 µA or more asleep, until the LED came off.
Illustrative figures using 200 mAh usable from a 235 mAh CR2032 coin cell (Energizer datasheet). Board measurements from the ESP32 community forum.
Security rules
The 2026 security rules, in plain English
Selling a connected product now comes with security rules. We build firmware to meet them from the first version, so you aren't rewriting code just before launch.
California SB-327
Law since January 2020: a unique password per device, or the user sets one first.
US Cyber Trust Mark
A voluntary FCC label, run by ioXt Alliance since April 2026. Not open to products yet.
EU Cyber Resilience Act
Bug reporting since September 2026. From December 2027, five years of security updates.
UK PSTI
Law since April 2024: no default passwords, a way to report bugs, a stated update period.
We design firmware to be label-ready. Lab testing and certificates are covered on our certification and compliance page.
Cost and time
What firmware development costs, honestly
Firmware cost depends on what your product has to do, not on lines of code. Here are published 2026 industry estimates.
- Simple sensor firmwareAbout $2,000 to $12,000 for one chip and basic logic
- Connected consumer deviceAbout $25,000 to $90,000, with power and updates
- Safe update systemAdds about $2,000 to $5,000
- Security featuresAdds about $4,000 to $10,000
- US engineer ratesAbout $100 to $180 an hour
- Typical timeline4 to 16 weeks for the firmware itself
Your price
What changes the price
- Number of sensors
- Wireless radio
- Safe updates
- Battery target
- Security rules
- Inherited code
Published industry estimates, checked November 2026. Ranges are wide because scope varies so much. Your fixed quote follows the free call.
Book my free 30-minute callYour options
Freelancer, firm or in-house?
| Freelancer | In-house hire | Inventornest | |
|---|---|---|---|
| Cost to start | Lowest hourly rate | Salary, benefits and hiring time | Fixed price per phase |
| Time to start | Days | Often months to hire | Days after the free call |
| Who owns the code | Depends on the contract | You | You, in writing |
| Keys and handover | Often missing | Yours | Handover box every phase |
| If they leave | Code can be stranded | Knowledge leaves with them | Documented so anyone continues |
| Board and housing | Usually firmware only | More hires needed | Same team, one roof |
How we work
Five steps, and you get something at each one
- 01Free 30-minute callA first view on the right chip, a cost band and the main risks.
- 02Behavior planEvery button, light, alert and sleep state, written and agreed.
- 03First firmware on your boardSensors read, radio connects and power measured on real boards.
- 04Field-ready buildSafe updates, security and battery targets tested on real units.
- 05Factory and handoverFactory files, test reports and your complete handover box.
Our own work
Chips and tools we work with
- Nordic nRF52 and nRF54
- ESP32
- STM32
- Silicon Labs
- Zephyr
- FreeRTOS
- ESP-IDF
- Bare metal
FAQ
Firmware questions inventors ask us
How much does firmware development cost?
Published 2026 industry estimates put simple sensor firmware at about $2,000 to $12,000 and a connected consumer device at about $25,000 to $90,000. Safe updates and security add a few thousand dollars each. After a free 30-minute call we give you a fixed quote for each phase.
How long does it take to develop firmware?
For the firmware itself, published guides put it at roughly 4 to 16 weeks, depending on sensors, wireless and updates. The whole product takes longer because the board, housing and certification run alongside it. We give you a dated plan after the free call.
Do I own the firmware source code?
Yes. The code lives in your own repository from day one, and at each phase we hand over build instructions, signing keys, factory files and test reports. A written IP assignment transfers all rights in the code to you.
My developer disappeared. Can you take over the code?
Yes. We review what you have, tell you honestly what works, and keep it where we can. You get a written list of what must be fixed or rewritten, with a price, before we change a line.
Can a firmware update brick my product?
Not if it's built properly. The new version downloads beside the old one, is checked against your signing key, and runs only if it starts correctly. If anything fails, the device restarts on the old version by itself.
How long will my product's battery last?
It depends on battery size and the average current the device draws, which firmware controls through sleep and radio timing. We estimate it before the board is built and then measure real units, because test boards often draw far more than the datasheet suggests.
Which chip should I use: ESP32, STM32 or Nordic?
Typically, ESP32 suits mains-powered Wi-Fi products, Nordic nRF chips suit battery-powered Bluetooth, Thread and Matter devices, and STM32 suits cost-sensitive products with simple wireless needs. We recommend one after looking at your battery, radio, cost and supply.
Do I need an RTOS or bare-metal firmware?
Simple products with one job often run best on bare metal: less code, less power. Products juggling wireless, sensors and updates usually need a small real-time operating system such as Zephyr or FreeRTOS. We pick whichever keeps your product simplest.
Can you start before my circuit board is finished?
Yes. We write and test firmware on development boards with the same chip while the board is designed, then move it to your board when it arrives. That saves weeks and catches board problems early.
Does my product need the US Cyber Trust Mark or meet the EU Cyber Resilience Act?
The Cyber Trust Mark is a voluntary FCC label and is not open to products yet. The EU Cyber Resilience Act applies to products sold in the EU, with full rules from December 2027. We design firmware to meet both, so you're ready either way.
Tell us about your idea
Share as much or as little as you like. An engineer reads every enquiry and replies within one business day, under NDA before you share details.