diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..68f3b10
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+# Devenv
+.devenv*
+devenv.local.nix
+devenv.local.yaml
diff --git a/README.md b/README.md
index 7df875b..9070e99 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,46 @@
 # [rssbase](https://rssbase.io)
 
+<details><summary>
+First, install tools
+</summary>
+
+## Developer environment
+
+The developer environment is handled by:
+- [devenv] is a tool for a fast, declarative, reproducible and composable developer environments using Nix
+- [nix] is a package manager, but also a programming language, used by devenv
+
+### Step by step commands
+
+```bash
+# Install nix
+curl -fsSL https://install.determinate.systems/nix | sh -s -- install --determinate
+
+# Nix optimisation
+gh auth status || gh auth login
+mkdir -p ~/.config/nix && echo "access-tokens = github.com=$(gh auth token)" >> ~/.config/nix/nix.conf
+sudo sh -c 'echo "trusted-users = root ${SUDO_USER:-$USER}" >> /etc/nix/nix.custom.conf'
+sudo sh -c 'echo "extra-substituters = https://devenv.cachix.org" >> /etc/nix/nix.custom.conf'
+sudo sh -c 'echo "extra-trusted-public-keys = devenv.cachix.org-1:w1cLUi8dv3hnoSPGAuibQv+f9TZLr6cv/Hm9XgU50cw=" >> /etc/nix/nix.custom.conf'
+sudo systemctl restart nix-daemon
+
+# Enable devenv auto activation
+if [[ "$SHELL" == */bash ]]; then
+  grep -qF 'devenv hook bash' ~/.bashrc || echo 'eval "$(devenv hook bash)"' >> ~/.bashrc
+elif [[ "$SHELL" == */zsh ]]; then
+  grep -qF 'devenv hook zsh' ~/.zshrc || echo 'eval "$(devenv hook zsh)"' >> ~/.zshrc
+elif [[ "$SHELL" == */fish ]]; then
+  grep -qF 'devenv hook fish' ~/.config/fish/config.fish || echo 'devenv hook fish | source' >> ~/.config/fish/config.fish
+else
+  open https://devenv.sh/auto-activation/
+fi
+
+# Get the codebase
+git clone git@tangled.org:mykiwi.dev/rssbase && cd rssbase
+devenv allow
+
+# Your developer environment is ready 👨‍🚀🚀
+```
+
+[devenv]: https://devenv.sh
+[nix]: https://search.nixos.org/packages
diff --git a/devenv.lock b/devenv.lock
new file mode 100644
index 0000000..07af2c8
--- /dev/null
+++ b/devenv.lock
@@ -0,0 +1,65 @@
+{
+  "nodes": {
+    "devenv": {
+      "locked": {
+        "dir": "src/modules",
+        "lastModified": 1782492839,
+        "narHash": "sha256-j9wrcB4al5QhMelEghJ0Qs+RQPT+wyCcI4070NEgPLQ=",
+        "owner": "cachix",
+        "repo": "devenv",
+        "rev": "3d39d0817d62069f7b18821c34a617b5141cb278",
+        "type": "github"
+      },
+      "original": {
+        "dir": "src/modules",
+        "owner": "cachix",
+        "repo": "devenv",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "inputs": {
+        "nixpkgs-src": "nixpkgs-src"
+      },
+      "locked": {
+        "lastModified": 1782132010,
+        "narHash": "sha256-ZnAVHdVrotp80iIMm5CSR1fdxPlw7Uwmwxb+O/wsgZ8=",
+        "owner": "cachix",
+        "repo": "devenv-nixpkgs",
+        "rev": "12866ae2dddbc0ab8b329915f8072bb9c75bde89",
+        "type": "github"
+      },
+      "original": {
+        "owner": "cachix",
+        "ref": "rolling",
+        "repo": "devenv-nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs-src": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1781607440,
+        "narHash": "sha256-rxO+uc/KFbSJp+pgyXRuAX6QlG9hJdnt0BXpEQRXY+U=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "3e41b24abd260e8f71dbe2f5737d24122f972158",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "devenv": "devenv",
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
\ No newline at end of file
diff --git a/devenv.nix b/devenv.nix
new file mode 100644
index 0000000..ec7e612
--- /dev/null
+++ b/devenv.nix
@@ -0,0 +1,19 @@
+{
+  pkgs,
+  ...
+}:
+
+{
+  # https://devenv.sh/packages/
+  packages = [ pkgs.git ];
+
+  # https://devenv.sh/basics/
+  enterShell = ''
+    echo "rssbase devenv:"
+    echo "- `git --version`"
+  '';
+
+  languages.nix.enable = true;
+
+  # See full reference at https://devenv.sh/reference/options/
+}
diff --git a/devenv.yaml b/devenv.yaml
new file mode 100644
index 0000000..3dcab58
--- /dev/null
+++ b/devenv.yaml
@@ -0,0 +1,18 @@
+# yaml-language-server: $schema=https://devenv.sh/devenv.schema.json
+inputs:
+  nixpkgs:
+    url: github:cachix/devenv-nixpkgs/rolling
+
+# If you're using non-OSS software, you can set allow_unfree to true.
+# allow_unfree: true
+
+# If you're not willing to allow unsupported packages:
+# allow_unsupported_system: false
+
+# If you're willing to use a package that's vulnerable
+# permitted_insecure_packages:
+#  - "openssl-1.1.1w"
+
+# If you have more than one devenv you can merge them
+#imports:
+# - ./backend