diff --git a/manifest.dhall b/manifest.dhall
index 42392d914968972c3863a162a057dcf956e99de0..14fa3a5050b97c4765320271947572871fddc7b9 100644
--- a/manifest.dhall
+++ b/manifest.dhall
@@ -573,6 +573,7 @@ in  [ callHackage "Cabal" "3.8.1.0"
     , callHackage "these" "1.1.1.1"
     , callHackage "these-skinny" "0.7.5"
     , callHackage "tf-random" "0.5"
+    , callHackage "th-expand-syns" "0.4.10.0"
     , callHackage "th-extras" "0.0.0.6"
     , callHackage "th-lift-instances" "0.1.20"
     , callHackage "tidal" "1.8.1"
diff --git a/overlay.nix b/overlay.nix
index 2c4192be0ec01b1fd57ba0c925712c111d0b6dcf..a8e2d24cbfaa84d5f8a1a47ab3582a97acc81785 100644
--- a/overlay.nix
+++ b/overlay.nix
@@ -773,6 +773,8 @@ final: prev: with pkgs.haskell.lib; {
 
   tf-random = prev.callPackage (./pkgs/tf-random.nix) { };
 
+  th-expand-syns = prev.callPackage (./pkgs/th-expand-syns.nix) { };
+
   th-extras = prev.callPackage (./pkgs/th-extras.nix) { };
 
   th-lift-instances = prev.callPackage (./pkgs/th-lift-instances.nix) { };
diff --git a/pkgs/th-expand-syns.nix b/pkgs/th-expand-syns.nix
new file mode 100644
index 0000000000000000000000000000000000000000..9d7034591d2961602f6d022e941f70d285b6e6a2
--- /dev/null
+++ b/pkgs/th-expand-syns.nix
@@ -0,0 +1,35 @@
+{ mkDerivation
+, base
+, containers
+, lib
+, syb
+, template-haskell
+, th-abstraction
+}:
+mkDerivation {
+  pname = "th-expand-syns";
+  version = "0.4.10.0";
+  sha256 = "f5455844e27578cf937c2eb670f15f6c10a45c29b2599e32bf308245360c9010";
+  isLibrary = true;
+  isExecutable = false;
+  enableSeparateDataOutput = false;
+  libraryHaskellDepends = [
+    base
+    containers
+    syb
+    template-haskell
+    th-abstraction
+  ];
+  testHaskellDepends = [ base template-haskell th-abstraction ];
+  enableLibraryProfiling = false;
+  enableExecutableProfiling = false;
+  doHaddock = false;
+  jailbreak = true;
+  doCheck = false;
+  doBenchmark = false;
+  hyperlinkSource = false;
+  homepage = "https://github.com/DanielSchuessler/th-expand-syns";
+  description = "Expands type synonyms in Template Haskell ASTs";
+  license = lib.licenses.bsd3;
+  broken = false;
+}