diff --git a/builder/comp-builder.nix b/builder/comp-builder.nix
index 60bce48716..ea9a1f05bd 100644
--- a/builder/comp-builder.nix
+++ b/builder/comp-builder.nix
@@ -447,6 +447,10 @@ let
       (lib.optionalString stdenv.hostPlatform.isGhcjs ''
       export HOME=$(mktemp -d)
       export EM_CACHE=$(mktemp -d)
+      if [ -d ${pkgsBuildBuild.emscripten}/share/emscripten/cache ]; then
+        cp -r ${pkgsBuildBuild.emscripten}/share/emscripten/cache/* $EM_CACHE/
+        chmod +w -R $EM_CACHE
+      fi
       '') +
       (lib.optionalString (!canCleanSource) ''
       echo "Cleaning component source not supported, leaving it un-cleaned"
diff --git a/ci.nix b/ci.nix
index 42d3ea0f3d..e07482ba5e 100644
--- a/ci.nix
+++ b/ci.nix
@@ -18,7 +18,7 @@
 
   # short names for nixpkgs versions
   nixpkgsVersions = {
-    "R2411" = inputs.nixpkgs-2411;
+    "R2505" = inputs.nixpkgs-2505;
     "unstable" = inputs.nixpkgs-unstable;
   };
 
@@ -43,6 +43,14 @@
         "libdwarf-20181024"
         "dwarfdump-20181024"
       ];
+      allowUnfreePredicate = pkg: builtins.elem (lib.getName pkg) [
+        "android-sdk-ndk"
+        "android-sdk-platform-tools"
+        "aarch64-unknown-linux-android-ndk-toolchain-wrapper"
+        "aarch64-unknown-linux-android-ndk-toolchain"
+        "armv7a-unknown-linux-androideabi-ndk-toolchain-wrapper"
+        "armv7a-unknown-linux-androideabi-ndk-toolchain"
+      ];
     };
   };
 
@@ -57,7 +65,7 @@
       # cabal-install and nix-tools plans.  When removing a ghc version
       # from here (so that is no longer cached) also remove ./materialized/ghcXXX.
       # Update supported-ghc-versions.md to reflect any changes made here.
-      nixpkgs.lib.optionalAttrs (nixpkgsName == "R2411") {
+      nixpkgs.lib.optionalAttrs (builtins.elem nixpkgsName ["R2411" "R2505"]) {
         ghc96 = true;
         ghc98 = true;
         ghc910 = true;
@@ -77,11 +85,7 @@
     let lib = nixpkgs.lib;
     in lib.optionalAttrs (nixpkgsName == "unstable"
       && (__match ".*llvm" compiler-nix-name == null)
-      && ((system == "x86_64-linux"  && !builtins.elem compiler-nix-name ["ghc902" "ghc928" "ghc948"])
-       || (system == "aarch64-linux" && !builtins.elem compiler-nix-name ["ghc902" "ghc928" "ghc948"])
-       || (system == "x86_64-darwin" && !builtins.elem compiler-nix-name ["ghc902" "ghc928" "ghc948" "ghc966" "ghc967" "ghc96720250227" "ghc982" "ghc983" "ghc984"])
-       || (system == "aarch64-darwin" && !builtins.elem compiler-nix-name ["ghc902" "ghc928" "ghc948" "ghc966" "ghc967" "ghc96720250227" "ghc982" "ghc983" "ghc984"])
-       )) {
+      && !builtins.elem compiler-nix-name ["ghc9102"]) {
     inherit (lib.systems.examples) ghcjs;
   } // lib.optionalAttrs (nixpkgsName == "unstable"
       && (__match ".*llvm" compiler-nix-name == null)
@@ -100,8 +104,10 @@
   } // lib.optionalAttrs (__match ".*llvm" compiler-nix-name == null && system == "x86_64-linux" && nixpkgsName == "unstable" && !builtins.elem compiler-nix-name ["ghc902" "ghc928" "ghc948"]) {
     # Out llvm versions of GHC seem to break for musl32
     inherit (lib.systems.examples) musl32;
-  } // lib.optionalAttrs (system == "x86_64-linux" && nixpkgsName == "R2411" && !builtins.elem compiler-nix-name ["ghc902" "ghc928" "ghc948"]) {
-    inherit (lib.systems.examples) aarch64-android-prebuilt armv7a-android-prebuilt;
+  } // lib.optionalAttrs (system == "x86_64-linux" && !builtins.elem compiler-nix-name ["ghc902" "ghc928" "ghc948"]) {
+    inherit (lib.systems.examples) aarch64-android-prebuilt;
+  } // lib.optionalAttrs (system == "x86_64-linux" && !builtins.elem compiler-nix-name ["ghc902" "ghc928" "ghc948" "ghc91320250523"]) {
+    inherit (lib.systems.examples) armv7a-android-prebuilt;
   } // lib.optionalAttrs (system == "x86_64-linux" && nixpkgsName == "unstable" && !builtins.elem compiler-nix-name ["ghc8107" "ghc902"]) {
     # TODO fix this for the compilers we build with hadrian (ghc >=9.4)
     inherit (lib.systems.examples) aarch64-multiplatform-musl;
diff --git a/compiler/ghc/default.nix b/compiler/ghc/default.nix
index 4189884671..9d31c197cf 100644
--- a/compiler/ghc/default.nix
+++ b/compiler/ghc/default.nix
@@ -422,9 +422,9 @@ haskell-nix.haskellLib.makeCompilerDeps (stdenv.mkDerivation (rec {
         export CXX="${targetCC}/bin/em++"
         export LD="${targetCC}/bin/emcc"
     '' + (
-      # Including AR and RANLIB here breaks tests.js-template-haskell for GHC 9.6
+      # Including AR and RANLIB here breaks tests.js-template-haskell for GHC <9.12
       # `LLVM ERROR: malformed uleb128, extends past end`
-      if builtins.compareVersions ghc-version "9.8" >= 0
+      if builtins.compareVersions ghc-version "9.12" >= 0
         then ''
           export AR="${targetCC}/bin/emar"
           export NM="${targetCC}/share/emscripten/emnm"
@@ -435,6 +435,10 @@ haskell-nix.haskellLib.makeCompilerDeps (stdenv.mkDerivation (rec {
         ''
     ) + ''
         export EM_CACHE=$(mktemp -d)
+        if [ -d ${targetCC}/share/emscripten/cache ]; then
+          cp -r ${targetCC}/share/emscripten/cache/* $EM_CACHE/
+          chmod +w -R $EM_CACHE
+        fi
         mv config.sub.ghcjs config.sub
     '')
     # GHC is a bit confused on its cross terminology, as these would normally be
diff --git a/default.nix b/default.nix
index ade481f5cb..c43181eb30 100644
--- a/default.nix
+++ b/default.nix
@@ -97,6 +97,9 @@ self // {
   pkgs-2411 = import self.inputs.nixpkgs-2411 (nixpkgsArgs // {
     localSystem = { inherit system; };
   });
+  pkgs-2505 = import self.inputs.nixpkgs-2505 (nixpkgsArgs // {
+    localSystem = { inherit system; };
+  });
   pkgs-unstable = import self.inputs.nixpkgs-unstable (nixpkgsArgs // {
     localSystem = { inherit system; };
   });
diff --git a/flake.lock b/flake.lock
index 6ce56435d5..adb9a3fbc0 100644
--- a/flake.lock
+++ b/flake.lock
@@ -372,11 +372,11 @@
     "iserv-proxy": {
       "flake": false,
       "locked": {
-        "lastModified": 1747047742,
-        "narHash": "sha256-PCDULyZSIPdDdF8Lanbcy+Dl6AJ5z6H2ng3sRsv+gwc=",
+        "lastModified": 1749176681,
+        "narHash": "sha256-RLoo84PBSeGKbqMETsU0lEJDnc/oTx0l/TYzCaWqlgc=",
         "owner": "stable-haskell",
         "repo": "iserv-proxy",
-        "rev": "dea34de4bde325aca22472c18d659bee7800b477",
+        "rev": "6972fbc49574108cb48723bb94260e3ce17898f7",
         "type": "github"
       },
       "original": {
@@ -436,11 +436,11 @@
     },
     "nixpkgs-2411": {
       "locked": {
-        "lastModified": 1746566971,
-        "narHash": "sha256-I40weT0FZWth1IEjgR5a0zC9LLyrPwTC0DAQcejtTJE=",
+        "lastModified": 1748037224,
+        "narHash": "sha256-92vihpZr6dwEMV6g98M5kHZIttrWahb9iRPBm1atcPk=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "209c5b3b0f5cf5b5a7e12ddea59bf19699f97e75",
+        "rev": "f09dede81861f3a83f7f06641ead34f02f37597f",
         "type": "github"
       },
       "original": {
@@ -450,13 +450,29 @@
         "type": "github"
       }
     },
+    "nixpkgs-2505": {
+      "locked": {
+        "lastModified": 1748852332,
+        "narHash": "sha256-r/wVJWmLYEqvrJKnL48r90Wn9HWX9SHFt6s4LhuTh7k=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "a8167f3cc2f991dd4d0055746df53dae5fd0c953",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-25.05-darwin",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
     "nixpkgs-unstable": {
       "locked": {
-        "lastModified": 1746576598,
-        "narHash": "sha256-FshoQvr6Aor5SnORVvh/ZdJ1Sa2U4ZrIMwKBX5k2wu0=",
+        "lastModified": 1748856973,
+        "narHash": "sha256-RlTsJUvvr8ErjPBsiwrGbbHYW8XbB/oek0Gi78XdWKg=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "b3582c75c7f21ce0b429898980eddbbf05c68e55",
+        "rev": "e4b09e47ace7d87de083786b404bf232eb6c89d8",
         "type": "github"
       },
       "original": {
@@ -515,6 +531,7 @@
         "nixpkgs-2311": "nixpkgs-2311",
         "nixpkgs-2405": "nixpkgs-2405",
         "nixpkgs-2411": "nixpkgs-2411",
+        "nixpkgs-2505": "nixpkgs-2505",
         "nixpkgs-unstable": "nixpkgs-unstable",
         "old-ghc-nix": "old-ghc-nix",
         "stackage": "stackage"
diff --git a/flake.nix b/flake.nix
index 017d695555..12f31554a9 100644
--- a/flake.nix
+++ b/flake.nix
@@ -7,6 +7,7 @@
     nixpkgs-2311 = { url = "github:NixOS/nixpkgs/nixpkgs-23.11-darwin"; };
     nixpkgs-2405 = { url = "github:NixOS/nixpkgs/nixpkgs-24.05-darwin"; };
     nixpkgs-2411 = { url = "github:NixOS/nixpkgs/nixpkgs-24.11-darwin"; };
+    nixpkgs-2505 = { url = "github:NixOS/nixpkgs/nixpkgs-25.05-darwin"; };
     nixpkgs-unstable = { url = "github:NixOS/nixpkgs/nixpkgs-unstable"; };
     flake-compat = { url = "github:input-output-hk/flake-compat/hkm/gitlab-fix"; flake = false; };
     "hls-1.10" = { url = "github:haskell/haskell-language-server/1.10.0.0"; flake = false; };
diff --git a/lazy-inputs/ghc913/flake.lock b/lazy-inputs/ghc913/flake.lock
index 15c5acd8a1..d73af49a22 100644
--- a/lazy-inputs/ghc913/flake.lock
+++ b/lazy-inputs/ghc913/flake.lock
@@ -3,11 +3,11 @@
     "ghc913": {
       "flake": false,
       "locked": {
-        "lastModified": 1735577639,
-        "narHash": "sha256-sGNckeL3B6Iw+3wawRjgFEXo/dLiyKAtnbFxY9tX6Qg=",
+        "lastModified": 1748027596,
+        "narHash": "sha256-5WU40R26lwl0lRTkEnWui8CEikZ9gRnbiOa4aw/GbI4=",
         "ref": "refs/heads/master",
-        "rev": "278a53ee698d961d97afb60be9db2d8bf60b4074",
-        "revCount": 67713,
+        "rev": "17db44c5b32fff82ea988fa4f1a233d1a27bdf57",
+        "revCount": 68114,
         "submodules": true,
         "type": "git",
         "url": "https://gitlab.haskell.org/ghc/ghc"
diff --git a/lib/supported-languages.nix b/lib/supported-languages.nix
index ee5ba8f194..0e459c0505 100644
--- a/lib/supported-languages.nix
+++ b/lib/supported-languages.nix
@@ -312,5 +312,11 @@ evalPackages.writeTextFile {
       NoMultilineStrings
       NamedDefaults
       NoNamedDefaults
+    ''
+    + pkgs.lib.optionalString (builtins.compareVersions ghc.version "9.13" >=0) ''
+      ExplicitLevelImports
+      ImplicitStagePersistence
+      NoExplicitLevelImports
+      NoImplicitStagePersistence
     ''}'';
 }
diff --git a/modules/component-options.nix b/modules/component-options.nix
index 4900e9d8d2..3fbc3cf803 100644
--- a/modules/component-options.nix
+++ b/modules/component-options.nix
@@ -1,4 +1,4 @@
-{ lib, haskellLib, ... }:
+{ pkgs, lib, haskellLib, ... }:
 {
   options = {
     buildable = lib.mkOption {
@@ -104,7 +104,8 @@
     enableStatic = lib.mkOption {
       description = "If set, enables building static libraries and executables.";
       type = lib.types.bool;
-      default = true;
+      # Disabled for ghcjs, see https://gitlab.haskell.org/ghc/ghc/-/issues/23235
+      default = !pkgs.stdenv.hostPlatform.isGhcjs;
     };
 
     enableShared = lib.mkOption {
diff --git a/modules/package.nix b/modules/package.nix
index 6a68a6bf78..39d9b2809f 100644
--- a/modules/package.nix
+++ b/modules/package.nix
@@ -10,7 +10,7 @@ let
 
   componentType = types.submodule [
     ./component.nix
-    { _module.args = { inherit haskellLib; }; }
+    { _module.args = { inherit pkgs haskellLib; }; }
     # pass down common options as default values
     ({ lib, options, ... }: lib.mkDefault (lib.filterAttrs (n: _v: builtins.hasAttr n options) config))
   ];
diff --git a/overlays/bootstrap.nix b/overlays/bootstrap.nix
index a57d60a187..5fe966e4ac 100644
--- a/overlays/bootstrap.nix
+++ b/overlays/bootstrap.nix
@@ -331,6 +331,9 @@ in {
 
                 ++ onAndroid (from      "9.6"          ./patches/ghc/ghc-9.6-COMPAT_R_ARM_PREL31.patch)
                 ++ onAndroid (from      "9.10"         ./patches/ghc/ghc-9.10-ignore-libc.patch)
+
+                # Fix for `fatal error: 'rts/Types.h' file not found` when building `primitive`
+                ++ onGhcjs (from        "9.13"         ./patches/ghc/ghc-9.13-ghcjs-rts-types.patch)
                 ;
         in ({
             ghc8107 = traceWarnOld "8.10" (final.callPackage ../compiler/ghc {
diff --git a/overlays/patches/ghc/ghc-9.13-ghcjs-rts-types.patch b/overlays/patches/ghc/ghc-9.13-ghcjs-rts-types.patch
new file mode 100644
index 0000000000..652e549f3c
--- /dev/null
+++ b/overlays/patches/ghc/ghc-9.13-ghcjs-rts-types.patch
@@ -0,0 +1,12 @@
+diff --git a/rts/rts.cabal b/rts/rts.cabal
+index 899e65d712..84dac99f54 100644
+--- a/rts/rts.cabal
++++ b/rts/rts.cabal
+@@ -160,6 +160,7 @@ library
+                         stg/MachRegs/x86.h
+                         stg/MachRegsForHost.h
+                         stg/Types.h
++                        rts/Types.h
+
+     else
+       -- If we are using an in-tree libffi then we must declare it as a bundled
diff --git a/test/cabal-22/default.nix b/test/cabal-22/default.nix
index ddbb51a63d..12345a395c 100644
--- a/test/cabal-22/default.nix
+++ b/test/cabal-22/default.nix
@@ -37,7 +37,7 @@ in recurseIntoAttrs {
     '' +
     # Aarch is statically linked and does not produce a .so file.
     # Musl is also statically linked, but it does make a .so file so we should check that still.
-    optionalString (!stdenv.hostPlatform.isAarch32 && !stdenv.hostPlatform.isAarch64) (''
+    optionalString (!stdenv.hostPlatform.isAarch32 && !stdenv.hostPlatform.isAarch64 || stdenv.hostPlatform.isDarwin) (''
       printf "checking that executable is dynamically linked to system libraries... " >& 2
     '' + optionalString (stdenv.isLinux && !stdenv.hostPlatform.isMusl) ''
       ${haskellLib.lddForTests} $exe | grep 'libc[.]so'
@@ -57,7 +57,7 @@ in recurseIntoAttrs {
     '' + optionalString stdenv.isLinux ''
       ${haskellLib.lddForTests} $sofile | grep libHSghc-prim
     '' + optionalString stdenv.isDarwin ''
-      otool -L $sofile | grep libHSghc-prim
+      otool -L $sofile | grep libHSghc-
     '')) + ''
       touch $out
 
diff --git a/test/cabal-simple-debug/default.nix b/test/cabal-simple-debug/default.nix
index 7b02425276..58d7aab01f 100644
--- a/test/cabal-simple-debug/default.nix
+++ b/test/cabal-simple-debug/default.nix
@@ -39,7 +39,7 @@ in recurseIntoAttrs {
         else ''
           (${dwarfdump}/bin/dwarfdump $exe || true) | grep -c 'libraries/base/[A-Za-z0-9/]*\.hs'
         ''}
-      (${dwarfdump}/bin/dwarfdump $exe || true) | grep -c '/Main\.hs'
+      (${dwarfdump}/bin/dwarfdump $exe || true) | grep -c 'Main\.hs'
 
       touch $out
     '';
diff --git a/test/cabal.project.local b/test/cabal.project.local
index 699d5493e7..d3e73d819b 100644
--- a/test/cabal.project.local
+++ b/test/cabal.project.local
@@ -9,8 +9,7 @@ if impl(ghc > 9.13)
   allow-newer: *:containers, *:time, *:ghc-bignum
   constraints: base-compat >=0.14.0, aeson >=2.2.1.0
   -- From https://ghc.gitlab.haskell.org/head.hackage/cabal.constraints
-  constraints: extra ==1.7.14
-  constraints: base-orphans <0.9.3 || >0.9.3
+  -- Nothing needed right now
 
 -- This prevents hsc2hs from causing old versions of packages from being added to plan.json
 allow-newer: hsc2hs:*
@@ -23,7 +22,7 @@ repository head.hackage.ghc.haskell.org
      f76d08be13e9a61a377a85e2fb63f4c5435d40f8feb3e12eb05905edb8cdea89
      26021a13b401500c8eb2761ca95c61f2d625bfef951b939a8124ed12ecf07329
      7541f32a4ccca4f97aea3b22f5e593ba2c0267546016b992dfadcd2fe944e55d
-  --sha256: sha256-ch17nc6wY2lr94j1+MULW7GuwtgQ8vz56yuPSADMmB8=
+  --sha256: sha256-Zu+OsPXt+tUllxC2LVJ3jneYGUH5GvdemZZPnynWaN0=
 
 repository ghcjs-overlay
   url: https://raw.githubusercontent.com/input-output-hk/hackage-overlay-ghcjs/ffb32dce467b9a4d27be759fdd2740a6edd09d0b
diff --git a/test/plugin/default.nix b/test/plugin/default.nix
index ae64225d96..3de0bc1b70 100644
--- a/test/plugin/default.nix
+++ b/test/plugin/default.nix
@@ -19,8 +19,8 @@ in recurseIntoAttrs {
   };
 
   # Not sure why this breaks for ghc 8.10.7
-  meta.disabled = compiler-nix-name == "ghc8107"
-    || builtins.elem compiler-nix-name [ "ghc9121" "ghc912120241215" "ghc91320241230" ]
+  meta.disabled =
+       builtins.elem compiler-nix-name [ "ghc91320250523" ]
     || stdenv.hostPlatform.isMusl
     || stdenv.hostPlatform.isGhcjs
     || stdenv.hostPlatform.isWindows
diff --git a/test/th-dlls/default.nix b/test/th-dlls/default.nix
index 8ee93eea0f..33315dc011 100644
--- a/test/th-dlls/default.nix
+++ b/test/th-dlls/default.nix
@@ -22,14 +22,16 @@ in recurseIntoAttrs {
   meta.disabled = stdenv.hostPlatform.isGhcjs
     # On aarch64 this test also breaks form musl builds (including cross compiles on x86_64-linux)
     || (stdenv.hostPlatform.isAarch64 && stdenv.hostPlatform.isMusl)
+    # Not sure why this is failing with a seg fault
+    || (builtins.elem compiler-nix-name ["ghc9102" "ghc9102llvm"] && stdenv.hostPlatform.isAndroid && stdenv.hostPlatform.isAarch32)
+    # unhandled ELF relocation(Rel) type 10
+    || (stdenv.hostPlatform.isMusl && stdenv.hostPlatform.isx86_32)
+
+    ## Old GHC versions (TODO remove)
     # Failed to lookup symbol: __aarch64_swp8_acq_rel
     || (builtins.elem compiler-nix-name ["ghc947" "ghc948"] && haskellLib.isCrossHost && stdenv.hostPlatform.isAarch64)
-    # Not sure why this is failing with a seg fault
-    || (builtins.elem compiler-nix-name ["ghc9102"] && stdenv.hostPlatform.isAndroid && stdenv.hostPlatform.isAarch32)
     # We have been unable to get windows cross compilation of th-orphans to work for GHC 8.10 using the latest nixpkgs
     || (compiler-nix-name == "ghc8107" && stdenv.hostPlatform.isWindows)
-    # unhandled ELF relocation(Rel) type 10
-    || (stdenv.hostPlatform.isMusl && stdenv.hostPlatform.isx86_32)
     ;
 
   ifdInputs = {
@@ -41,7 +43,7 @@ in recurseIntoAttrs {
   build-ei = packages-ei.th-dlls.components.library;
   just-template-haskell-ei = packages-ei.th-dlls.components.exes.just-template-haskell;
 } // optionalAttrs
-    (!(builtins.elem compiler-nix-name ["ghc984" "ghc9121" "ghc912120241215" "ghc91320241230" "ghc912120250219"]  && stdenv.buildPlatform.isx86_64 && stdenv.hostPlatform.isAarch64)) {
+    (!(builtins.elem compiler-nix-name ["ghc984" "ghc9122" "ghc91320250523"]  && stdenv.buildPlatform.isx86_64 && stdenv.hostPlatform.isAarch64)) {
   # On for aarch64 cross compile on GHC this test is fails sometimes for non profiled builds
   # (and always for the profiled builds).
   # This may be related to the memory allocation changes made in 9.8.4 that