diff --git a/pkgs/development/coq-modules/equations/default.nix b/pkgs/development/coq-modules/equations/default.nix
index e6d5e11fcc5f..f563d1728744 100644
--- a/pkgs/development/coq-modules/equations/default.nix
+++ b/pkgs/development/coq-modules/equations/default.nix
@@ -7,7 +7,7 @@ with lib; mkCoqDerivation {
   inherit version;
   defaultVersion = switch coq.coq-version [
     { case = "8.14"; out = "1.3-8.14"; }
-    { case = "8.13"; out = "1.2.4+coq8.13"; }
+    { case = "8.13"; out = "1.3-8.13"; }
     { case = "8.12"; out = "1.2.4+coq8.12"; }
     { case = "8.11"; out = "1.2.4+coq8.11"; }
     { case = "8.10"; out = "1.2.1+coq8.10-2"; }
@@ -44,6 +44,8 @@ with lib; mkCoqDerivation {
     release."1.2.4+coq8.12".sha256    = "1n0w8is464qcq8mk2mv7amaf0khbjz5mpc9phf0rhpjm0lb22cb3";
     release."1.2.4+coq8.13".rev       = "v1.2.4-8.13";
     release."1.2.4+coq8.13".sha256    = "0i014lshsdflzw6h0qxra9d2f0q82vffxv2f29awbb9ad0p4rq4q";
+    release."1.3-8.13".rev            = "v1.3-8.13";
+    release."1.3-8.13".sha256         = "1jwjbkkkk4bwf6pz4zzz8fy5bb17aqyf4smkja59rgj9ya6nrdhg";
     release."1.3-8.14".rev            = "v1.3-8.14";
     release."1.3-8.14".sha256         = "19bj9nncd1r9g4273h5qx35gs3i4bw5z9bhjni24b413hyj55hkv";