diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index f76728bd62cf..e8ccd4346644 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -16738,7 +16738,7 @@ in
     inherit (ocamlPackages) ocaml findlib lablgtk;
     camlp5 = ocamlPackages.camlp5_transitional;
   };
-  coq = coq_8_6;
+  coq = coq_8_4;
 
   mkCoqPackages_8_4 = self: let callPackage = newScope self; in {
     inherit callPackage;
@@ -16805,7 +16805,7 @@ in
   coqPackages_8_4 = mkCoqPackages_8_4 coqPackages_8_4;
   coqPackages_8_5 = mkCoqPackages_8_5 coqPackages_8_5;
   coqPackages_8_6 = mkCoqPackages_8_6 coqPackages_8_6;
-  coqPackages = coqPackages_8_6;
+  coqPackages = coqPackages_8_4;
 
   cryptoverif = callPackage ../applications/science/logic/cryptoverif { };