How we work.
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Hands-on Craftsmanship
We love our craft and care about every project we take on. Teams working with us appreciate our hands-on, tailored approach and the way we engage closely to create the best solutions.
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No false promises
We start by carefully listening to what each project truly needs. Instead of standardized approaches or easy promises, we work honestly and personally, making sure expectations and solutions are clear from the start.
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Collaborative approach
Our team brings deep, practical knowledge across systems, tooling, and infrastructure. We work collaboratively with each other and with our clients, combining skills to tackle complex problems effectively and efficiently.
A team of independent engineers that love open source.
As a team of software engineers who enjoy open source and building systems, we work with teams in R&D, robotics, financial, and SaaS. In our projects, we mainly use Nix and NixOS as a superpower to improve reliability and quality, with many of our engineers deeply embedded in the ecosystem. Numtide was founded by Jonas Chevalier in 2012 and has since been an environment for like-minded engineers who enjoy working closely together on challenging projects.
Our commitment to
Open Source.
As a long-standing member of the open-source community, we support a range of projects, conferences, and events, including NixCon 2026 and sprint funding. Explore our work and connect with our team at the upcoming events listed below.
Explore our work:
Open Source Projects:
flake-utils - The standard utility library for Nix flakes.
ethereum.nix - Reproducible Ethereum infrastructure with Nix.
system-manager - Manage system config with Nix on any distro.
treefmt - The universal code formatter multiplexer.
llm-agents.nix - Nix packages for AI coding agents.
blueprint - Standard project structure for Nix.
Talk to us: Upcoming Events & Conference
Meet the magic behind.
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Jonas Chevalier
Founder
Switzerland- Herding of Geeks
Jonas Chevalier
Jonas founded Numtide and created direnv, a per-directory environment manager used by thousands of developers worldwide. He has been shaping the NixOS ecosystem for over 10 years, helping establish the NixOS Foundation, NixCon, and the nix-community organization. When not running the business, he builds tools like treefmt and system-manager to solve real-world infrastructure problems.
Projects
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Dragan Milic
Team Lead
Switzerland- Distributed Networking
- Databases
- Ethereum
Dragan Milic
Dragan has a PhD in distributed overlay networks from the University of Bern and a track record of shipping under pressure -- from backend systems at Monzo Bank to leading the Arkiv Network team, where he took an Ethereum L3 data platform from zero to mainnet. Give him a big technical problem and a team, and he will deliver.
Projects
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Jorg Thalheim
Germany- Builder of tools
- Chief of Automation
Jorg Thalheim
Jorg is one of the most prolific toolmakers in the Nix ecosystem. With a PhD from the University of Edinburgh, he created sops-nix, nixos-anywhere, and nix-direnv -- tools with thousands of stars each that are now standard in NixOS workflows. He currently leads the Clan project and serves on the Nix and NixOS infrastructure teams.
Projects
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Adam Hose
New Zealand Adam Hose
If you need Python, Go, or any language ecosystem to work seamlessly with Nix, Adam is the person who figured out how. He created poetry2nix, pyproject.nix, and uv2nix -- the standard tools for Python-Nix integration -- and his abstractions are used across the entire Nix community.
Projects
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Florian Klink
Estonia- Nix
- Rust
- DevOps
- Embedded systems
Florian Klink
Florian is reimagining how Nix works from the ground up. As the lead author of Snix and the top contributor to tvix before it, he is building a Rust re-implementation of the Nix package manager with content-addressed storage, OCI-compatible builders, and monorepo-scale ambitions. He has deep knowledge of operating system internals and low-level systems design.
Projects
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Brian McGee
Ireland- Go
- Nix
- Embedded
Brian McGee
Brian came from the world of high-frequency trading and now applies that same performance mindset to Nix infrastructure. He co-maintains treefmt and leads narwal, the garbage collection system keeping cache.nixos.org in shape, as well as nits, a pull-based NixOS deployment tool built on NATS.
Projects
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Aldo Borrero
Spain- System Engineer
- DevOps
- SRE
Aldo Borrero
Aldo built the bridge between Ethereum and Nix. As lead maintainer of ethereum.nix, he provides the Nix packages and NixOS modules that the Ethereum ecosystem relies on -- from execution and consensus clients to validators. He is a relentless executor who thrives under tight deadlines.
Projects
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Julien Malka
France- Software Supply Chain Security
Julien Malka
Julien is pursuing a PhD in software supply chain security at Telecom Paris and already making an outsized impact on the NixOS ecosystem. He co-maintains proxmox-nixos, built lila to verify build reproducibility at scale, and sits on the NixOS Steering Committee. His academic rigor in security and formal verification translates directly into more trustworthy infrastructure.
Projects
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Antony Ducommun
Switzerland- System architect
Antony Ducommun
Antony has touched every layer of the software stack, from embedded systems and 3D engines to distributed architectures and machine learning pipelines. His recent work uses LLMs as intelligent query interfaces for financial systems -- having the model write programs to execute queries, then translating results back into formulas quants can verify. He is the person you call when you need a complex system designed and built end to end.
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Jeffrey Cogswell
USA- Technical Writer
Jeffrey Cogswell
Jeffrey has authored over ten programming books, including the O'Reilly C++ Cookbook. Unlike most technical writers, he is also a working developer -- which means he actually understands what he is writing about. That combination of writing craft and engineering depth makes his documentation unusually clear and accurate.
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Richard Brezak
Netherlands- Haskell
- Nix
Richard Brezak
Richard tackles hard build infrastructure problems. He created NixNG, a lightweight Nix-based Linux distribution purpose-built for containers, and is a core contributor to buildbot-nix, bringing Buildbot's CI capabilities deep into the Nix ecosystem. He is also pushing the boundaries of Nix evaluation to make it scale to monorepo-sized projects.
Projects
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Stefan Junker
Switzerland- Rust
- Distributed Systems
Stefan Junker
Stefan's career runs through the heart of distributed systems -- from container networking at Red Hat (as a CNI project member) to peer-to-peer computing at Holochain. He now leads nix-fleet, an NLnet-funded tool for managing fleets of NixOS machines across complex network topologies.
Projects
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Chris O’Brien
USA- Rust
- Nix
- Web3
Chris O’Brien
Chris built jinx, a statically typed Nix compiler in Rust -- bringing the kind of type-safety that TypeScript brought to JavaScript into the Nix world. He combines deep Rust and Nix expertise with Web3 experience from building deployment infrastructure for the Versatus decentralized compute platform.
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Ryota Sawada
UK- Kubernetes
- Nix
- Go
Ryota Sawada
Ryota is the Release Team Lead for Kubernetes v1.36 and a member of the Istio community. He previously built Kubernetes operators at Civo. At Numtide, he brings this deep Kubernetes expertise to bear on integrating Nix with the container ecosystem -- and his talent for writing clear specifications makes him invaluable for communicating technical ideas across teams.
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Fernando Villalba
Spain- PM
- Kubernetes
Fernando Villalba
Fernando has over a decade of experience consulting for large organizations on infrastructure delivery and Kubernetes adoption. He publishes "The Personable Engineer," a newsletter on DevOps and platform engineering. At Numtide, he bridges engineering teams and stakeholders -- turning complex technical decisions into clear plans everyone can align on.
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Félix Baylac Jacqué
France- DevOps
- Nix
- NixOS
Félix Baylac Jacqué
Felix's code runs on every NixOS machine -- his nsncd daemon has shipped as the default NSS lookup service since NixOS 23.05. He runs his own ISP, contributes to the Nix CLI and nixpkgs, and serves on the NixOS moderation team. His deep experience in networking and datacenter operations comes from running real infrastructure.
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Ramses de Roche
Belgium- Rust
- Haskell
- DevOps
- Nix
- NixOS
Ramses de Roche
Before joining Numtide, Ramses helped deploy NixOS to Doctors Without Borders field machines -- systems now used by medical teams saving lives every day. He is the primary author of system-manager for declarative Linux configuration and one of the most active nixpkgs contributors with over 600 commits.
Projects
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Jean-Francois Roche
Belgium- DevOps
- Nix
- NixOS
Jean-Francois Roche
Jean-Francois has over 15 years of DevOps experience and a reputation for quietly getting things done. Point him at an infrastructure problem, and he will figure it out on his own. He brings deep expertise in CI/CD, infrastructure automation, and Nix-based system configuration.
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Lorenzo Manacorda
Spain- Nix
- DevOps
- Rust
Lorenzo Manacorda
Lorenzo is deeply embedded in the Nix ecosystem, with over 125 pull requests to nixpkgs and contributions to the Nix core itself. His background spans systems programming in Rust, infrastructure automation, and blockchain development.
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Võ Minh Thu
Belgium- Haskell
- Nix
Võ Minh Thu
Thu founded Hypered, a Belgian software consultancy, and brings 15+ years of Haskell and Nix expertise. A former CTO who chose to go back to hands-on engineering, he is the author of nix-notes and has published Haskell libraries spanning GLSL parsing, Docker registries, and ACME certificate management.
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Paul Haerle
Austria- DevOps
- Nix
- NixOS
Paul Haerle
Paul is a prolific NixOS contributor with close to 300 nixpkgs commits and hands-on contributions to disko and nixos-anywhere. He runs NixCon workshops and built nixos-vm-on-macos to bring NixOS to Apple hardware. He has a knack for finding the practical path through complex infrastructure problems.
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Patrick Morris
Ireland- Rust
- Nix
- Web3
Patrick Morris
Patrick works at the intersection of Nix, Rust, and the Ethereum ecosystem. He builds tooling for secrets management and smart contract development, and contributes across the Nix ecosystem -- from nixpkgs to disko to nix-unit.
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Samuel Rounce
UK- DevOps
- Rust
- JavaScript
Samuel Rounce
Samuel brings 15+ years of experience across JavaScript, Rust, and infrastructure automation. He has contributed to Numtide's Blueprint framework and builds practical tools like keyps for SSH key provisioning. His breadth across the stack makes him effective wherever he is needed.
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Yvan Sraka
Belgium- Rust
- Haskell
- Nix
- DevOps
Yvan Sraka
Yvan trained in mathematics and computer science at Sorbonne University and spent his time at IOG solving one of the hardest interop problems around -- bridging Rust and Haskell with hs-bindgen and cargo-cabal. He is a regular speaker at FOSDEM and NixCon, and brings deep expertise in functional programming, Nix, and developer tooling.
We believe great projects start with careful listening. Instead of standardised approaches or easy promises, we work honestly and personally, valuing craftsmanship and responsibility for what we build.
The most challenging projects are also the most fun, because that’s when we get to roll up our sleeves and really dive in.