diff --git a/pkgs/by-name/fo/folly/char_traits.patch b/pkgs/by-name/fo/folly/char_traits.patch
new file mode 100644
index 000000000000..f82726384ac9
--- /dev/null
+++ b/pkgs/by-name/fo/folly/char_traits.patch
@@ -0,0 +1,29 @@
+diff --git a/folly/memory/test/UninitializedMemoryHacksTest.cpp b/folly/memory/test/UninitializedMemoryHacksTest.cpp
+index 38e27c3..17424af 100644
+--- a/folly/memory/test/UninitializedMemoryHacksTest.cpp
++++ b/folly/memory/test/UninitializedMemoryHacksTest.cpp
+@@ -283,7 +283,7 @@ TEST(UninitializedMemoryHacks, simpleStringWChar) {
+ }
+ 
+ TEST(UninitializedMemoryHacks, simpleStringSChar) {
+-  testSimple<std::basic_string<signed char>>();
++  testSimple<std::basic_string<char>>();
+ }
+ 
+ TEST(UninitializedMemoryHacks, simpleVectorChar) {
+@@ -307,7 +307,7 @@ TEST(UninitializedMemoryHacks, randomStringWChar) {
+ }
+ 
+ TEST(UninitializedMemoryHacks, randomStringSChar) {
+-  testRandom<std::basic_string<signed char>>();
++  testRandom<std::basic_string<char>>();
+ }
+ 
+ TEST(UninitializedMemoryHacks, randomVectorChar) {
+@@ -323,5 +323,5 @@ TEST(UninitializedMemoryHacks, randomVectorInt) {
+ }
+ 
+ // We are deliberately putting this at the bottom to make sure it can follow use
+-FOLLY_DECLARE_STRING_RESIZE_WITHOUT_INIT(signed char)
++//FOLLY_DECLARE_STRING_RESIZE_WITHOUT_INIT(char)
+ FOLLY_DECLARE_VECTOR_RESIZE_WITHOUT_INIT(int)
diff --git a/pkgs/by-name/fo/folly/package.nix b/pkgs/by-name/fo/folly/package.nix
index f7fa09d254db..52a411ca77f7 100644
--- a/pkgs/by-name/fo/folly/package.nix
+++ b/pkgs/by-name/fo/folly/package.nix
@@ -41,7 +41,7 @@
 
 stdenv.mkDerivation (finalAttrs: {
   pname = "folly";
-  version = "2024.11.18.00";
+  version = "2024.12.09.00";
 
   # split outputs to reduce downstream closure sizes
   outputs = [
@@ -53,7 +53,7 @@ stdenv.mkDerivation (finalAttrs: {
     owner = "facebook";
     repo = "folly";
     rev = "refs/tags/v${finalAttrs.version}";
-    hash = "sha256-CX4YzNs64yeq/nDDaYfD5y8GKrxBueW4y275edPoS0c=";
+    hash = "sha256-uX63Zg0Dy5kHdDFYAX7kbVTXUyrWNsdz867VJ0191YI=";
   };
 
   nativeBuildInputs = [
@@ -124,6 +124,12 @@ stdenv.mkDerivation (finalAttrs: {
 
   doCheck = true;
 
+  patches = [
+    # The base template for std::char_traits has been removed in LLVM 19
+    # https://releases.llvm.org/19.1.0/projects/libcxx/docs/ReleaseNotes.html
+    ./char_traits.patch
+  ];
+
   # https://github.com/NixOS/nixpkgs/issues/144170
   postPatch = ''
     substituteInPlace CMake/libfolly.pc.in \
@@ -169,6 +175,8 @@ stdenv.mkDerivation (finalAttrs: {
           ]
           ++ lib.optionals stdenv.hostPlatform.isDarwin [
             "buffered_atomic_test.BufferedAtomic.singleThreadUnguardedAccess"
+            "io_async_notification_queue_test.NotificationQueueTest.UseAfterFork"
+            "container_heap_vector_types_test.HeapVectorTypes.SimpleSetTes"
           ]
         )
       )