diff --git a/README.md b/README.md
index 74b69c5..b21aaff 100644
--- a/README.md
+++ b/README.md
@@ -37,3 +37,18 @@ popd
 ```
 
 followed by another rebuild.
+
+## Troubleshooting
+
+### command-not-found unable to connect to database
+
+The programs.sqlite is only generated for the nixos- prefixed channels.
+
+Run the following as root:
+
+```sh
+nix-channel --add https://nixos.org/channels/nixos-unstable nixos
+nix-channel --update
+```
+
+Further reading: [NixOS discourse](https://discourse.nixos.org/t/command-not-found-unable-to-open-database/3807).