diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 9708c39d8..2190396a8 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -94,6 +94,14 @@ For instance running a crawler:
 nix run . -- lentille github-projects --url https://api.github.com/graphql --token <a-valid-token> --organization change-metrics
 ```
 
+### Build the documentation
+
+Build and read the code documentation:
+
+```
+just docs
+```
+
 ## nix-develop
 
 The nix develop shell provides development tooling such as:
diff --git a/Justfile b/Justfile
index 52a17c807..a773eee70 100644
--- a/Justfile
+++ b/Justfile
@@ -46,6 +46,10 @@ test pattern:
 ghcid:
     nix develop --command ghcid
 
+# Build and open the documentation
+docs:
+    nix develop --command cabal haddock --open
+
 # Start hoogle with local monocle documentation
 hoogle-monocle:
     nix develop .#hoogle-monocle --command hoogle server -p 8081 --local --haskell