diff --git a/hosts/biolimo/biolimo.nix b/hosts/biolimo/biolimo.nix
index 47c961ff..62af3bf6 100644
--- a/hosts/biolimo/biolimo.nix
+++ b/hosts/biolimo/biolimo.nix
@@ -40,5 +40,10 @@ in {
           inkscape
         ];
       };
+
+    # For OpenProject development with https
+    security.pki.certificates = [
+      (builtins.readFile ./step-roots.pem)
+    ];
   };
 }
diff --git a/hosts/biolimo/step-roots.pem b/hosts/biolimo/step-roots.pem
new file mode 100644
index 00000000..ae6b9a47
--- /dev/null
+++ b/hosts/biolimo/step-roots.pem
@@ -0,0 +1,12 @@
+-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----