diff --git a/pkgs/build-support/fetchbzr/nix-prefetch-bzr b/pkgs/build-support/fetchbzr/nix-prefetch-bzr
index dbe8a7ef8013..184f2485ce57 100755
--- a/pkgs/build-support/fetchbzr/nix-prefetch-bzr
+++ b/pkgs/build-support/fetchbzr/nix-prefetch-bzr
@@ -9,7 +9,7 @@ if test -z "$hashType"; then
     hashType=sha256
 fi
 if test -z "$hashFormat"; then
-    hashFormat=--base32
+    hashFormat=--sri
 fi
 
 if test -z "$url"; then