Next step
Tell me what you're building
Send me a short description of the problem and I'll tell you whether I'm the right fit, what it would cost, and how long it would take. No pitch deck.
- Phone
- +46 70 753 73 78
- elinorwigertz
Fixed-price delivery
You hand me the problem. I hand back a working system, with the source, the drawings and the documentation your team needs to run it without me.
Fixed price, agreed upfront. Start with feasibility if the shape of the product is still open.
Product Feasibility
€6k
1-2 weeks
Architecture, the build-versus-buy call and a parts strategy, a risk list, and a fixed price for the build. Credited in full against the build if you go ahead.
Product Build
from€40k
6-10 weeks
A working product, sensor to screen, delivered into production with the source and documentation your team needs to own it.
Product Programme
from€100k
6+ months
A product taken through production, deployment and live operation: assembly, field support, and the tooling your team runs it with afterwards.
What sits outside the price
Components, manufacturing, and third-party services billed at cost. Complexity adds time and cost, discussed upfront.
All prices excl. VAT.
Example deliveries
A good fit when
Probably not when
One person accountable for the entire system, from circuit board to production deployment.
Sensor choice, firmware, backend, frontend, and the mechanical parts in between. Nothing waits on a handover between specialists, because there are none.
Mud Masters: concept to 50+ stations in the field in about ten weeks.
Not only client work. I founded a hardware company and took it through certification and production, which is where you find out what shipping actually costs.
Lifee: circuit design to App Store, 1000+ units.
Wiring diagrams, BOM, deployment guides, source. The handover is designed in from the start rather than assembled in the last week.
Lynes: the patterns were still in use years after I left.
Recovery, monitoring and the failure cases are part of the first design, because a demo that cannot survive a power cut is not a product.
Mud Masters: standalone, offline-first, recovers on its own.
A fixed price is only worth anything if the estimate holds.
Spec first, then agents in parallel
I work spec-driven: the plan, the interfaces and the failure cases are settled before implementation starts. That makes the work separable, so I run coding agents against those plans in parallel rather than typing every line myself. What does not get delegated is the judgement, and that is the part a fixed price rests on: what to build and what to buy, where the risk actually sits, what gets reviewed before it ships, and when the scope has quietly moved. It is how a build an agency would staff with a small team runs here as one engagement, and why I quote a price for the outcome rather than a rate for my time.
Proven parts first, custom where it earns it
Most connected products do not need custom silicon. On the GYMRACE scoring stations I chose a Raspberry Pi, an off-the-shelf LiDAR module with a plain serial interface, and 3D-printed mounts, because a part you can buy again in two years is worth more than a board that is five percent tidier. Custom hardware is a decision with a long tail: respins, lead times, certification, and a replacement problem when a component goes end-of-life. I design around that by default, and go custom when nothing off the shelf will do the job. Two products of mine have been through a full radio sweep for CE, which is mostly how I know when you can avoid one.
Sensor evaluation and selection, compute platform selection (Raspberry Pi, ESP32, custom PCB), wiring and cabling design, power system design.
3D printed enclosures and mounts (PLA, PETG, Polycarbonate), CAD design for sensor mounts and brackets, aperture and clearance calculations, production-ready 3D print files with BOM.
FreeRTOS, bare-metal C, Linux-based systems, sensor drivers, signal processing and filtering, hit/event detection algorithms.
React frontends, Node.js/TypeScript backends, Go and Dart/Serverpod services, real-time data streaming (SSE, WebSockets), diagnostic and development tooling, kiosk/display applications.
BLE, WiFi, LoRa, Zigbee, Cellular. Mobile apps (React Native). Cloud backends. OTA updates. Not every product needs this. I add connectivity only when the product requires it.
CI/CD pipelines, Docker containerization, Kubernetes deployment on GKE/EKS/AKS, GitOps (Flux, ArgoCD), monitoring (Prometheus/Grafana), bill of materials, assembly instructions, field testing support.
You describe the problem, I ask questions
Fixed price, clear deliverables, timeline
Regular updates, no surprises
Working system, documentation, source code

Founder & Technical Lead
IoT Health Tracker for Children
Hardware and software from scratch. Custom PCB, BLE firmware, React Native app, OTA updates, CE certification, production line setup.
Outcome
Fully working product from scratch: 1000+ units shipped, measurable health improvements in 10+ schools

Principal Engineer
Real-time scoring system for GYMRACE fitness competitions
Real-time scoring system for GYMRACE fitness competitions across Europe. Sensor-based hit detection, custom hardware mounts, plug-and-play kiosk stations. 50+ stations delivered.
Outcome
Delivered from scratch: 50+ stations assembled, plug-and-play kiosk image, automated build pipeline, full documentation and source handed over. Deployed for GYMRACE fitness competitions across Europe.

Principal Engineer
Automated CI/CD Platform for Unity Game Studio
Replaced manual builds with fully automated CI/CD pipelines. GitHub Actions, auto-scaling AWS runners, automated Steam deployments, zero idle costs.
Outcome
Fully automated build and release pipeline replacing manual process, zero idle compute costs, modular multi-game CI/CD with auto-scaling ephemeral infrastructure

Firmware & Application Developer
Advanced Humidity Monitoring System
Firmware, measurement algorithm and app for non-invasive moisture monitoring in buildings. Passive in-wall sensors, handheld reader, CE radio certification.
Outcome
A working system for non-invasive moisture measurement in buildings, read through the wall and shown in the app

Developer & System Architect
Interactive Festival Multiplayer Game
Wall-projected multiplayer game for Vinterljus light festival 2023. AWS backend, Next.js frontend, MQTT real-time multiplayer, browser-based controls.
Outcome
A wall-projected festival game played from a phone browser, 10-20+ at once and several hundred over an evening

System Developer & Hardware Engineer
Wearable ECG Monitor Hardware Redesign
Hardware redesign for a wearable ECG monitor. Added BLE connectivity and large storage capacity, with new firmware and C drivers.
Outcome
Successfully delivered updated hardware with BLE connectivity and expanded storage for wearable ECG monitoring
Project images
Next step
Send me a short description of the problem and I'll tell you whether I'm the right fit, what it would cost, and how long it would take. No pitch deck.