01
Technical systems
Infrastructure, networking, security, performance, and debugging. The critical layers of the stack that don't fix themselves.
Open to new engagements
We make solutions that let you sleep at night.
systems
security
performance
infrastructure
processes
01 — Where we work
At the junction
of four disciplines.
Most problems worth hiring for don't sit cleanly in one column of the org chart. We're comfortable moving between them — listening where decisions are made, and working where the code runs.
02
Operations
The day-to-day reality of on-call rotations, maintenance windows, and vendor coordination. Writing the runbooks that were never written.
03
Administration
Documentation, access control, and audit trails. Crafting policy that actually reflects how your team works — and how they should.
04
Management
Reading the room and translating between engineering and the business. Helping decisions land where they need to.
02 — How we engage
From the first question
to long after handover.
Three phases, one team all the way through. We don't believe in the consultant-hands-it-to-the-contractor-hands-it-to-the-vendor chain — it's where most of the quality leaks out.
01
Analyze
/ identify/ gather/ map
We listen first — to the people on the team, to the system itself, to the decisions that brought you here. Then we write it down plainly.
AuditsInterviewsWritten RFCs
02
Build
/ propose/ build/ deploy
We propose, design, procure, integrate, and ship. Short cycles and production-grade output, with no handoffs to mystery teams.
SystemsSoftwareIntegrations
03
Persevere
/ test/ maintain/ transfer
The hardest part of a good system is the second year. We stick around to test, measure, document and transfer knowledge until it runs without us.
OpsDocsHandover
Open-source case study
Proxmox restores
up to six times faster.
We rewrote how Proxmox Backup Server loads chunks during restore — turning a sequential bottleneck into parallel work. The patch "restore: make chunk loading more parallel" was accepted upstream on 15 July 2025 and ships to every Proxmox user for free.
Engineered by NOT NULL Makers, sponsored by ČMIS. Covered by Lupa.cz as a Czech contribution to a major VMware alternative.
10 GiB system disk× 5.7
BEFORE
869 MB/s
AFTER
4 992 MB/s
100 GiB random-data disk× 4.2
BEFORE
245 MB/s
AFTER
1 020 MB/s
✓
Merged upstream
pve-devel · 15 Jul 2025
NOT NULL Makers & FUDO Security
03 — Partnership
Privileged access,
made operational.
Securing privileged environments demands careful technical alignment. As Fudo Security's exclusive Czech partner, NOT NULL Makers provide the necessary review, implementation, migration, evolution and ongoing localized support to help organizations make informed access management decisions within their broader security and infrastructure concept.
- Whole lifecycle support in Czech, English or German.
- Consultation, Implementation, Migration.
About the product
Designed for enterprise environments, Fudo provides agentless Privileged Access Management to secure all privileged sessions. By eliminating endpoint installations, it streamlines infrastructure integration & contractor onboarding. The platform optionally leverages AI biometric profiling to continuously analyze behavioral signals, automatically terminating compromised sessions in real time.
1,400+
Behavioral signals
100s
Enterprise deployments
0
Agents on endpoints
04 — What we stand for
Building software that ages well.
A handful of engineering principles shape every system we build. They are why our systems age well.
01
Simple, not easy
When we say simple, we mean something specific: one thing doing one job, standing on its own. That's different from easy, which is whatever happens to be familiar and close at hand. The two often look alike at the start but behave very differently over time. Simple designs stay readable and affordable to maintain, year after year, which is why we reach for them first, even when they require finding.
02
Think before building
Most of the real work happens before we write any code. We spend the first week describing the problem on a single page: what it is, what we're solving, and what we're setting aside. Once the problem is clear, the code tends to follow quickly, and it tends to be the right code.
03
Data over structure
We model our systems around plain data: simple lists and tables of values that any part of the system can read directly. One shared shape with many small functions around it stays easy to read, test, and extend as the system grows. This is why the teams who inherit our code five years later can still read it.
04
Add, don't replace
Good software grows by adding. When we release a new version, code that depended on the old one keeps working. New features arrive as additions. Upgrading to a new version should feel like a small step forward, and most of the time, it is.
05 — Selected work
A glimpse of our work.
CHUNK LOADING
sequential → parallel
5.7×
Open-source impact2025
Proxmox Backup Server
Parallelized chunk loading in Proxmox Backup Server's restore path. Investigated the bottleneck across the Rust and C boundary, prototyped a fix, and worked with Proxmox maintainers through three rounds of review. Benchmarked at 5.7× on our test rig, lifting restore throughput from around 300 MB/s to over 1 GB/s on customer systems. Merged upstream in July 2025 and now shipping to every Proxmox user.
Funded by ČMIS · Built by NOT NULL Makers.
LAUNCH & BEYOND
pressure → calm
REGULATED
BRIEFPROTOTYPEINTEGRATIONCOMPLIANCELIVE
High-stakes deliveryConfidential
Financial broker · trading platform
Joined the development of a regulated broker's trading platform shortly before rollout, under time pressure. Shipped fixes, usability improvements, and new features at pace through the launch period. As the codebase stabilized, we stayed on, gradually taking over from the original developers. Today we are the team that keeps it running and shapes where it goes next.
In our care.
DATA CENTER MODERNIZATION
old estate → new estate
LIVE
research continues · zero downtime
Zero downtimeConfidential
Research company · data center
Modernized the data center of a market and public opinion research company well-known across the Czech Republic. Scoped the investment case, advised through vendor negotiations and licensing, and worked alongside the client through installation and cutover, including nights and weekends, to keep active research running throughout.
Advised, installed, handed over.
Ready when you are
Let's start a conversation.
The easiest way in is a message, as short or as long as feels right, in your own words. From there, we take our time. We read, we think, and we come back to you with questions or a time to meet.