A 24×24 programmable LED display. Two people. Two years.
Starting in 2023, Ronald and Sefa, a hardware specialist, began building a 24×24 programmable LED display you could code in C# or F#, with a browser simulator that works before any hardware arrives.
Two years of weekends later: firmware rewritten three times, PCBs hand-soldered, 3D-printed dome parts produced in-house, CE certification completed, packaging designed end-to-end, photography commissioned from a professional studio.
One limited batch of 100 units — each assembled by the two of them.
This is not a startup story. It's the discipline Ronald brings to your team.The cast
Engineer · API · Firmware · Cloud
C#/F#/TypeScript. Designs the developer-facing C# API for the PXL Clock, the F# daemon that runs on the device, the cloud backend with signed OTA, the VS Code simulator. Also: community Discord, PXL-JAM, and the consulting practice this page exists to describe.
Hardware · Production · Assembly
PCB design, component sourcing, soldering, power management, mechanical assembly, 3D-printing workflow, batch production. The reason 100 units actually leave the workshop — crimped, soldered, and press-fit by hand.
The company
Hand-built limited batches, 100 units per run. No factory. The constraint is not money — it is care.
The timeline
Raspberry Pi + WS2812B LED strip experiments. PWM vs. PCM vs. SPI tradeoffs worked out on paper and in hand.
Float-glass and Polycarbonat/PETG/ASA from Lithuanian suppliers. CraftCloud pilots: €63–160 per 10-unit run.
Power budget set at 60 W. Bill of materials locked.
F# daemon ran the render loop. The C# simulator's hot-reload began returning results in under a second.
Black or white frame? High-tech production powered by .NET, WhatsApp'd from the printer farm.
Community hackathon for C#/F# pixel-art apps. Three clocks given away. F# Advent Calendar slot.
Users could set their own apps as default clock / sleep app. Tested without the real device. Nothing bricked.
Three minutes from git clone to a first pixel visible. C# and F# first; TypeScript and JavaScript in the roadmap.
EMC test report May. Safety test report July 4. Declaration of Conformity drafted. Six months of back-and-forth with an outsourced lab.
Custom cardboard (28×28×9 cm), foam inserts, branded Avery stickers, A5 printed manuals in DE/EN. No contract packaging.
1.5-day studio session; 80+ clips, 121 edited stills. Hero photography for the launch.
Hand-built and crafted, 576 glowing 3D pixels, 100 units available — made with care, not mass-produced.
Clock app appearance reworked. TypeScript SDK in beta. Python API in planning.
2023 · Origin
A 24×24 matrix you can program in C# or F#. No shortcut, no vendor stack. If it works on paper — build it. Two people, weekends, a soldering iron.
Jan 2025 · Trust
Signed firmware, rollback-safe, remote. From that day forward the clock was a product, not a hobby. The consulting discipline — "don't brick the customer" — applied to our own hardware first.
Nov 2025 · Ship
Two years of side-project hustle. Solder, crimp, print, press-fit, screw, box. Two to four hours per device. No factory between us and the customer. The constraint is care.
What's genuinely hard
14 A worst-case at full white, clamped to a 60 W PSU. PWM timing via SPI/PCM; no flicker tolerated. Thermal management matters for certification.
Render loop locked to 60 FPS while WiFi reconnect, OTA download, and temperature throttling run alongside. State-aware rendering on an embedded device — deliberate, not clever.
Stateful components, async/await, hooks-style patterns — compiled to run deterministically on the embedded host.
Three minutes from git clone to first pixel visible. Zero hardware required to start. Removes the single biggest friction that kills hobbyist hardware platforms.
TypeScript/Express + PostgreSQL + Auth0 + React/Ionic/Capacitor on iOS and Android. Signed OTA firmware, user accounts, app storage, device management.
Watchdog plus dual-partition strategy. A bad update does not brick the device.
EMC (emissions + immunity), RoHS, product safety. Six months of back-and-forth; outsourced lab, in-house compliance docs.
Every unit hand-assembled: solder two PCBs, crimp AC adapter cables, 3D-print ~200 dome parts, press-fit LEDs, screw frame, box. Two to four hours per device. The 100-unit cap is a time budget, not a business decision.
Custom branded cardboard, foam inserts, Avery stickers, printed DE/EN A5 manuals. No contract packaging — every choice our own.
Logo in-house and polished with Wabaki. Professional photo + video shoot. Pixel-art avatars by Marc Duiker. Community showcase apps by Urs Enzler.
Signal, not noise
We started #pxlclock as two good friends — Sefa & me… 100 units selling soon — Who with us for party?
— Bluesky · 2025-08-12Why we only sell 100 #pxlclock units? Main one is: we are manufacturing the clock all by ourselves. PXL Clock is hand-made manufacturing work.
— Bluesky · 2025-08-12When I tell that #pxlclock is hand-made, this means: Man, it's hand-made. You see Sefa in Action — life and in color, soldering the 2 boards for the clock. Thank god I'm a programmer…
— Bluesky · 2025-11-09#pxlclock is finally here 🎉 Hand-built and crafted, with 576 glowing 3D pixels. Only 100 units available right now — made with care, not mass-produced.
— Bluesky · 2025-11-04#pxlclock update is online. You can now set your own app as the default. I can currently only test it without the real device, so in case anything goes wrong, tell me :)
— Bluesky · 2025-01-09After 2 years of serious side-project hustle, we've built a limited batch of 100 PXL Clocks — a programmable clock for developers and design lovers.
— Bluesky · 2025-11-08The reframe
This is the consulting pitch made literal. Ronald didn't buy his way to "pragmatic engineering" as a slogan — he practices it where nobody is paying him. When he recommends that your team keep the know-how in-house instead of outsourcing to fifty contractors, he is recommending what he does with Sefa.
When he argues against buzzword compliance, against the Scrum industry, against the "two-week shine" of expensive consulting, he is arguing from a side-project that shipped because it didn't do those things.
If your team wants that same clarity — AI adoption that actually sticks, a codebase that survives the quarter, a team that stays sharper after he's gone — that is the engagement.
How we work together
01
A diagnostic for product teams that know AI belongs in the roadmap but aren't sure where. Output: a shortlist of AI moves that fit your product, your stack, your team — with effort and risk estimates you can defend in the next board meeting.
02
A short, high-bandwidth engagement that leaves your developers able to ship the next thing without outside help. Pair-programming, reviews, dedicated spikes around a real problem — on your codebase, with your people.
03
A neutral, time-boxed read of where your system is heading. You get a written argument — what's working, what's decaying, what moves next — plus a senior voice who is neither selling you a replatform nor defending the status quo.
04
For teams stuck in ceremony theater. We identify the two or three practices that actually produce value and recommend what to drop — starting from the Agile Manifesto, not the framework textbook.
05
When the problem is so nested — AI + functional architecture + DSL + developer tooling — that a tool-hire makes sense, I take on the build, pair with your team, and hand it back fully documented.
About
Fifteen years in .NET. Creator of FsHttp (invited by Don Syme to fsprojects) and several OSS libraries the F# community uses. Recognized F# Expert, 2019.
Co-founder — with Sefa — of the PXL Clock, a programmable 24×24 LED display shipping via Cumin & Potato GmbH. Real hardware, real firmware, real customers. Small team. Shipped without a framework textbook.
Based in Frankfurt. Work with DACH and remote-EU teams. Trading as PureState IT Consulting.
The next step
No calendar link, no "book a slot". A conversation first.