diff --git a/pkgs/development/compilers/llvm/default.nix b/pkgs/development/compilers/llvm/default.nix
index 28742b65cd72..b6cdcc547344 100644
--- a/pkgs/development/compilers/llvm/default.nix
+++ b/pkgs/development/compilers/llvm/default.nix
@@ -27,10 +27,18 @@ let
     "20.1.8".officialRelease.sha256 = "sha256-ysyB/EYxi2qE9fD5x/F2zI4vjn8UDoo1Z9ukiIrjFGw=";
     "21.1.8".officialRelease.sha256 = "sha256-pgd8g9Yfvp7abjCCKSmIn1smAROjqtfZaJkaUkBSKW0=";
     "22.1.5".officialRelease.sha256 = "sha256-eunfMOH+HVpefZJ+CG7hXDoM+pi6iYvHpD3DoSAsjoE=";
-    "23.0.0-git".gitRelease = {
-      rev = "7d24dfa5f29e1794e452aadaa27f994f15568763";
-      rev-version = "23.0.0-unstable-2026-07-12";
-      sha256 = "sha256-mHiwOqEvqXyG6OoiVLRrhzb2MK7FqjQm9ez329ngbYw=";
+    "23.1.0-rc1" = {
+      gitRelease = {
+        rev = "acdf320b78fcf075ddcf660b51cf18d5c0af755b";
+        rev-version = "23.1.0-rc1";
+        sha256 = "sha256-kSfy7IRgF/2HX5Fr3OS5LTXx7xm/iUx7tWb27e4wO+s=";
+      };
+      name = "23";
+    };
+    "24.0.0-git".gitRelease = {
+      rev = "43a704b657423a0eead02e64911b413c4afca73f";
+      rev-version = "24.0.0-unstable-2026-07-26";
+      sha256 = "sha256-wXhYrz3g5F7iwVqgIVryfRtkQ+3lKIKRDd9D8X18dEE=";
     };
   }
   // llvmVersions;
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 863622227bc4..90a14da2bef3 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -4179,6 +4179,8 @@ with pkgs;
       bolt_22 = llvmPackages_22.bolt;
       flang_22 = llvmPackages_22.flang;
 
+      llvmPackages_23 = llvmPackagesSet."23";
+
       mkLLVMPackages = llvmPackagesSet.mkPackage;
     })
     llvmPackages_18
@@ -4213,6 +4215,7 @@ with pkgs;
     llvm_22
     bolt_22
     flang_22
+    llvmPackages_23
     mkLLVMPackages
     ;