A recent release of Nickel added algebraic data types and pattern matching. This blog post explains the motivation behind this addition, the design choices made, the considerations around backward compatibility and how ADTs can be useful for a configuration language.

Implementing an equivalent to the NixOS module system in Nickel

A report on another 18 months in Nix documentation.

We re-implemented the nix remote protocol, declaratively

We just came out of Kubecon 2024. Here are our impressions of the trends and evolutions in infrastructure, configuration management and cloud native computing

This is an answer to a request for comments issued by CISA about software identifiers that CISA encouraged me to publish as a separate blog post.

Creating infrastructure for supporting Bazel remote execution with rules_nixpkgs

Introducing the lib.fileset Nix library for easy and safe source filtering

tl;dr: We’re pleased to announce the beta release of Organist, a tool designed to ease the definition of reliable and low-friction development environments and workflows, building on the combined strengths of Nix and Nickel. A mess of cables and knobs I used to play piano as a…

Building the foundation to analyze your Software Supply Chain in Nix

Today, I am very excited to announce the 1.0 release of Nickel. A bit more than one year ago, we released the very first public version Nickel (0.1). Throughout various write-ups and public talks (1, 2, 3), we’ve been telling the story of our dissatisfaction with the state of…

We went to FOSDEM23 and CfgMgmtCamp23. Here are my impressions of the trends and evolutions in infrastructure and configuration management

We present opam-nix, show how it helps to easily develop, build and test your OCaml projects with Nix

Make your NixOS development on macOS easier with this simple trick...

jupyterWith gets a new name and updates.

The Nix `with` keyword is challenging, but we transpiled it to Nickel anyway.

Getting an old Make based project building again after 10 years with the help of Bazel and Nix.

An internship report on my experience working on improving search.nixos.org and my internship at Tweag

Announcing the next version of jupyterWith.

Setup two encrypted partitions with a shared Nix store

Comparing Nix input hashes can guarantee that some refactors are bug-free.

A comprehensive report on what happened in four months of dedicated work on Nix documentation, and what I learned from it.

Learn the options for building a Nix flake out of a Rust workspace, outputting a mix of native code and WebAssembly.

A nixpkgs content database with graph building!

Cleanly and seamlessly add unit tests to your nix functions.

Introducing the Scalable Build Systems Team

How and when to use NixOS specialisations to manage different boot environments

Tweag's Nix team plans for the coming years

Nix is all about applying functional programming to files and processes.

Integrating Haskell Stack and Nix in a smooth yet non-invasive way, with an explanation, example and template.

How to get reproducible development environments for probabilistic programming packages such as PyMC3, Theano or TensorFlow using Nix.

Why union and intersection contracts are hard in a lazy language, and how Nickel handles them.

I am excited to announce the first release of Nickel! In the original introductory blog post, I’ve written about why we, at Tweag, are developing yet another configuration language. Our goal is to empower people to write correct, programmable and maintainable configurations…

We discuss existing consensus models and why no global consensus mode is well suited to Trustix, opting for a user-defined algorithm instead.

In this post we introduce Merkle trees, the data structures needed to make the Trustix log append-only and searchable.

Overview of the new features in Nix 2.4 and 2.5

Details about the 21.11 Nix Moscow Hackaton, and some suggestions for organizers of similar events.

What had to change in the Nix internals to make it able to build content-addressed derivations?

A dive into Nickel's gradual type system, which mixes dynamic and static typing

Better Go packaging with Gomod2nix

This is another blog post on the upcoming content-addressed derivations for Nix. We’ve already explained the feature and some of its advantages, as well as the reasons why it isn’t easy to implement. Now we’re going to talk about about a concrete user-facing change that this…

Presenting Nickel: better configuration for less Programming with contracts in Nickel Types à la carte in Nickel Great Nickel configurations from little merges grow In a previous post, I gave a taste of Nickel, a configuration language we are developing at Tweag. One cool feature…

Trustix aims at enhancing trust in software binaries and improve reproducibility tracking using distributed binary caches.

Why wasn't Nix built with a content-addressed store?

Presenting Nickel: better configuration for less Programming with contracts in Nickel Types à la carte in Nickel Great Nickel configurations from little merges grow We are making the Nickel repository public. Nickel is an experimental configuration language developed at Tweag…

Bazel gains support for creating fully statically linked Haskell binaries with rules_haskell and rules_nixpkgs.

In making a build system for your software, you codified the dependencies between its parts. But, did you account for implicit software dependencies, like system libraries and compiler toolchains? Implicit dependencies give rise to the biggest and most common problem with…

Why content-addressability is desirable for Nix.

What do we need to focus on to increase adoption of Nix?

Learn how to use Nix to create highly reproducible Python builds that are aware of native dependencies.

How to manage NixOS systems using Nix flakes.

How to setup a Buildkite-based CI for Nix projects with workers running on GCP.

How Nix flakes enable caching of evaluation results of Nix expressions.

How Nix is collaborating with Software Heritage for long-term software reproducibility.

An introduction to Nix flakes and a tutorial on how to use them.

Learn how Nix's new post-build hooks feature can automatically sign and upload artifacts to a binary cache in a trusted way.

Today we’re excited to announce lorri, a new tool for NixOS, Linux, and macOS that makes developing with Nix even nicer: When people try lorri, we often hear that it is more magical than they expected. What is lorri? lorri is a nix-shell replacement for project development…

In a recent project I was tasked with creating a local testing environment for a Kubernetes cluster the client was actively working on. The main requirements were: Cross platform: It should work on Linux and macOS. Ease of use: The setup should be easy to use. Suitable for CI…

Millions of Jupyter notebooks are spread over the internet - machine learning, astrophysics, biology, economy, you name it. What a great age for reproducible science! Or that's what you think until you try to actually run these notebooks. Then you realize that having understandable high-level code alone is not enough to reproduce something on a computer. JupyterWith is a solution to this problem.

The repositories of distributions such as Debian and Nixpkgs are among the largest collections of open source (and some unfree) software. They are complex systems that connect and organize many interdependent packages. In this blog post I'll try to shed some light on them from the perspective of Nixpkgs, mostly with visualizations of its complete dependency graph.

This is the second post in our series about building polyglot projects using Bazel. You might find it useful to start with our first installment. A is an extraordinary thing. You specify a set of targets, you tell Make what the dependencies are between these targets, and Make…

Nix on Windows: does it run yet? That’s the question I wondered about while testing the latest NixOS release, version 17.09. To that end, I had the idea of running the Nix installation process from inside the Windows Subsystem for Linux (WSL) see if it worked. And it worked…

Théophane is a summer intern here at Tweag I/O. Thanks also in part to the financial help from the Nix community, he’s spending six months on devising a type system for the Nix language. Nix, the purely functional package manager Nix is a cross platform tool for managing the…

Stack and Cabal are great tools for incremental development. But before even starting to think about what your first commit will be about on a freshly checked out project, what you have to do is get a working development environment, by which we mean: see if it builds! Stack…