document components

lib.nix

@@ -1,10 +1,12 @@
 { pkgs, nix_templater }:
 rec {
+  # placeholder to be substituted with the content of a secret file
   fileContents = file: {
    outPath = "<${builtins.placeholder "nix_template"}${toString file}${builtins.placeholder "nix_template"}>";
    file = file;
   };
 
+  # make a template with placeholders
   template_text = { name, text, outPath }:
     pkgs.runCommand name {
       textBeforeTemplate = text;

pkgs/nix_templater/replace.py

@@ -1,3 +1,4 @@
+# replace occurrences of a magic string in a template file
 import sys
 from pathlib import Path
 

tests/template.nix

@@ -1,3 +1,4 @@
+# test injecting a secret into a template
 { legacyPackages, system, nixpkgs }:
 let
   # this file would usually be outside of the store