diff --git a/pkgs/os-specific/bsd/openbsd/default.nix b/pkgs/os-specific/bsd/openbsd/default.nix
index aa12d73079b6..c49f1b3e807a 100644
--- a/pkgs/os-specific/bsd/openbsd/default.nix
+++ b/pkgs/os-specific/bsd/openbsd/default.nix
@@ -20,7 +20,7 @@ makeScopeWithSplicing' {
       directory = ./pkgs;
     }
     // {
-      version = "7.5";
+      version = "7.9";
 
       stdenvLibcMinimal = stdenvNoLibc.override (old: {
         cc = old.cc.override {
diff --git a/pkgs/os-specific/bsd/openbsd/pkgs/libcMinimal/package.nix b/pkgs/os-specific/bsd/openbsd/pkgs/libcMinimal/package.nix
index 52c2d56c00d3..c4cfab61fec7 100644
--- a/pkgs/os-specific/bsd/openbsd/pkgs/libcMinimal/package.nix
+++ b/pkgs/os-specific/bsd/openbsd/pkgs/libcMinimal/package.nix
@@ -60,6 +60,7 @@ mkDerivation {
   env.NIX_CFLAGS_COMPILE = toString [
     "-B${csu}/lib"
     "-Wno-error"
+    "-fno-builtin"
   ];
 
   # Suppress lld >= 16 undefined version errors
@@ -73,6 +74,11 @@ mkDerivation {
     "LIBC_TAGS=no"
   ];
 
+  # -fret-clean requires OpenBSD-specific patches to the compiler.
+  postPatch = ''
+    find . -type f -exec sed -i 's/-fret-clean//g' {} \;
+  '';
+
   postInstall = ''
     pushd ${include}
     find include -type d -exec mkdir -p "$dev/{}" ';'
diff --git a/pkgs/os-specific/bsd/openbsd/pkgs/rtld/package.nix b/pkgs/os-specific/bsd/openbsd/pkgs/rtld/package.nix
index 58fd1fd8ebd4..8e6a1478f1f9 100644
--- a/pkgs/os-specific/bsd/openbsd/pkgs/rtld/package.nix
+++ b/pkgs/os-specific/bsd/openbsd/pkgs/rtld/package.nix
@@ -17,6 +17,13 @@ mkDerivation {
 
   NIX_CFLAGS_COMPILE = "-Wno-error";
 
+  makeFlags = [ "STACK_PROTECTOR=1" ];
+
+  # -fret-clean requires OpenBSD-specific patches to the compiler.
+  postPatch = ''
+    find . -type f -exec sed -i 's/-fret-clean//g' {} \;
+  '';
+
   # DESTDIR is overridden in bsdSetupHook, just fixup afterwards
   postInstall = ''
     mv $out/bin $out/libexec
diff --git a/pkgs/os-specific/bsd/openbsd/pkgs/source.nix b/pkgs/os-specific/bsd/openbsd/pkgs/source.nix
index a92dfbd2b221..e770df9ce9fd 100644
--- a/pkgs/os-specific/bsd/openbsd/pkgs/source.nix
+++ b/pkgs/os-specific/bsd/openbsd/pkgs/source.nix
@@ -7,6 +7,6 @@
 fetchcvs {
   cvsRoot = "anoncvs@anoncvs.fr.openbsd.org/cvs";
   module = "src";
-  tag = "OPENBSD_${lib.replaceStrings [ "." ] [ "_" ] version}-RELEASE";
-  sha256 = "sha256-hzdATew6h/FQV72SWtg3YvUXdPoGjm2SoUS7m3c3fSU=";
+  tag = "OPENBSD_${lib.replaceStrings [ "." ] [ "_" ] version}_BASE";
+  sha256 = "sha256-n6pkgjCvqAGpZzLZnsO8FT7HMtBH3i7SLfhFBqQ9jmE=";
 }