Add python and node virtualenvs

README.md

@@ -2,4 +2,4 @@
 
 This is a repository for different virtual environments, which can be used with the **Nix** package manager.
 
-Just clone the content of the desired folder to your project, add your required packages to the `requirements.txt` file and run `nix-shell`.
+Just clone the content of the desired folder to your project, add your required packages to the `*.txt` file and run `nix-shell`.

node_environment/default.nix

@@ -0,0 +1,19 @@
+with import <nixpkgs> {};
+
+stdenv.mkDerivation {
+  name = "myNodeEnv";
+  buildInputs = with pkgs; [
+    nodejs
+  ];
+  src = null;
+  shellHook = ''
+    mkdir -p .npm
+    if [ -s global_packages.txt ]; then
+      cat global_packages.txt | xargs npm install -g --prefix $PWD/.npm
+    fi
+    if [ -s package.json ]; then
+      npm install
+    fi
+    export PATH=$PWD/.npm/bin:$PATH
+  '';
+}

python_environment/default.nix

@@ -0,0 +1,20 @@
+with import <nixpkgs> {};
+
+stdenv.mkDerivation {
+  name = "myPythonEnv";
+  buildInputs = with pkgs; [
+    python36Full
+    python36Packages.virtualenv
+    python36Packages.pip
+  ];
+  src = null;
+  shellHook = ''
+    # set SOURCE_DATE_EPOCH so that we can use python wheels
+    SOURCE_DATE_EPOCH=$(date +%s)
+    virtualenv --no-setuptools venv
+    export PATH=$PWD/venv/bin:$PATH
+    if [ -s requirements.txt ]; then
+      pip install -r requirements.txt
+    fi
+  '';
+}