diff --git a/pkgs/build-support/fetchpijul/default.nix b/pkgs/build-support/fetchpijul/default.nix
index ca7e1a7926e80..fd41cfa55355c 100644
--- a/pkgs/build-support/fetchpijul/default.nix
+++ b/pkgs/build-support/fetchpijul/default.nix
@@ -1,4 +1,4 @@
-{ lib, stdenvNoCC, pijul }:
+{ lib, stdenvNoCC, pijul, cacert }:
 
 lib.makeOverridable (
 { url
@@ -17,7 +17,8 @@ if change != null && state != null then
 else
   stdenvNoCC.mkDerivation {
     inherit name;
-    nativeBuildInputs = [ pijul ];
+    nativeBuildInputs = [ pijul cacert ];
+    strictDeps = true;
 
     dontUnpack = true;
     dontConfigure = true;
@@ -52,5 +53,7 @@ else
       lib.fakeSha256;
 
     inherit url change state channel;
+
+    impureEnvVars = lib.fetchers.proxyImpureEnvVars;
   }
 )