features VS asdf

Dev Containers not only allow you to define which extensions should be installed and which configuration settings shall be set, but they also have something they call "Dev Container Features".

json { "name": "Ubuntu", // Or use a Dockerfile or Docker Compose file. More info: https://containers.dev/guide/dockerfile "image": "mcr.microsoft.com/devcontainers/base:ubuntu", "features": { "ghcr.io/devcontainers/features/terraform": "latest", "ghcr.io/devcontainers/features/powershell": "latest", "ghcr.io/devcontainers/features/azure-cli": "latest" }, // Features to add to the dev container. More info: https://containers.dev/features. // "features": {}, // Use 'forwardPorts' to make a list of ports inside the container available locally. // "forwardPorts": [], // Use 'postCreateCommand' to run commands after the container is created. // "postStartCommand": "uname -a", // "postCreateCommand": "sudo apt update; sudo apt upgrade -y;", "postAttachCommand": { "git-safe-directory": "git config --global --add safe.directory ${containerWorkspaceFolder}", "ansible_cfg_permissions": "sudo chmod o-w ${containerWorkspaceFolder}" }, "postCreateCommand": { "python": "sudo apt update; sudo apt upgrade -y; sudo apt install -y python3-pip postgresql-client; sudo python3 -m pip install --upgrade pip; pip3 install ansible python-hcl2 psycopg2-binary; ansible-galaxy collection install azure.azcollection", "populate-history": "echo 'ansible-playbook ansible/playbooks/netbox.yml' >> ~/.bash_history; echo 'terraform apply' >> ~/.bash_history; echo 'az login' >> ~/.bash_history" }, // Configure tool-specific properties. // "customizations": {}, // Uncomment to connect as root instead. More info: https://aka.ms/dev-containers-non-root. // "remoteUser": "root" "customizations": { "vscode": { "extensions": [ "GitHub.copilot", "GitHub.copilot-labs", "GitHub.vscode-pull-request-github", "redhat.ansible", "hashicorp.terraform", "ms-toolsai.jupyter", "ms-vscode.powershell", "HashiCorp.terraform", "eamodio.gitlens", "GitHub.copilot-chat" ] } } }

there are already built docker images for common development environment. You can either use one of them, or build one from Docker file. Using a pre-built dev container doesn't mean you are only limited to that image, because you can still add other tools, which they are called features to that image. For a list of the pre-built templates check here, and for the other features that you can add check this. You don't need a Docker file, unless you want to build your dev environment step by step.

// For format details, see https://aka.ms/devcontainer.json. For config options, see the // README at: https://github.com/devcontainers/templates/tree/main/src/python { "name": "Python 3", "image": "mcr.microsoft.com/devcontainers/python:0-3.11", "features": { "ghcr.io/devcontainers/features/python:1": {} } // Features to add to the dev container. More info: https://containers.dev/features. // "features": {}, // Use 'forwardPorts' to make a list of ports inside the container available locally. // "forwardPorts": [], // Use 'postCreateCommand' to run commands after the container is created. // "postCreateCommand": "pip3 install --user -r requirements.txt", // Configure tool-specific properties. // "customizations": {}, // Uncomment to connect as root instead. More info: https://aka.ms/dev-containers-non-root. // "remoteUser": "root" }

This is actually very easy. I've implemented a number of tools like this publicly but the standard doesn't limit you to public stuff. I can't emphasize enough the amount of speed we gained when we implemented this standard. https://containers.dev/features

features: While you can add everything in Dockerfile for the build, there are already pre-configured features you can optionally add. You can find the complete list of the features at here. Some examples of those features are common utilities and tools like Azure CLI, GitHub CLI and Terraform, and languages like node.js, Java, .NET, Python, etc.

Or if you need to manage more than just node, asdf has been around for over a decade and works great. You can use a .tool-versions to change runtimes for each project you have, in addition to managing your global runtime versions

https://asdf-vm.com/

Why not just use a tool like asdf (https://asdf-vm.com/) or mise (https://mise.jdx.dev/)?

These tools have the advantage of not being multi-taskers and can manage version for all your tools. You wouldn’t need pyenv and npm and rvm and…

We’ve even started committing the .mise.toml files for projects to our repos. That way, since we work on multiple projects that may need multiple versions of the same tool, it’s handled and documented.

The purpose of a version manager is to help you navigate or install any tools for development easily. Version Manager can be one tool for each dependency (e.g. NVM, g) or One tool for all dependencies (e.g. asdf, mise).

(asdf)[https://asdf-vm.com/] fully supports Python and almost any other language. I've been using it for Ruby, Python, Elixir, and other languages for years and never looked back.

Secondly, our development environments must not drift, because then code may behave differently and a change could pass on our machine but fail in production. There are many tools for locking down environments, e.g nix, pkgx, asdf, containers, etc., and they all share the common goal of being able to lock down dependencies for an environment accurately and deterministically. And that needs to be enforced in our local workflow so we don't have to rely on CI environments for correctness. All developers must have environments that are effectively identical to what runs in CI (which itself should be representative of the production environment).

There are many ways this can be done (e.g nix, pkgx, asdf, containers, etc.), and we won’t get into which specific tools to use, because we'll instead cover the essential essence of preventing environment drift:

I've really been enjoying asdf, which is a program that allows you to install specified versions of dev utilities as well as dynamically manage them via shims and .tool-versions files.

I use the asdf version manager.