diff --git a/hooks/default.nix b/hooks/default.nix
index 5d56201..20f1756 100644
--- a/hooks/default.nix
+++ b/hooks/default.nix
@@ -3,15 +3,18 @@
 , makeSetupHook
 , wheel
 , pip
+, pkgs
 }:
 let
   callPackage = python.pythonForBuild.pkgs.callPackage;
   pythonInterpreter = python.pythonForBuild.interpreter;
   pythonSitePackages = python.sitePackages;
+  nonOverlayedPython = pkgs.python3.pythonForBuild.withPackages (ps: [ ps.tomlkit ]);
 in
 {
-
-  removePathDependenciesHook = callPackage
+  # NOTE: We have to use a non-overlayed Python here because otherwise we run into an infinite recursion
+  # because building of tomlkit and its dependencies also use these hooks.
+  removePathDependenciesHook = nonOverlayedPython.pkgs.callPackage
     (
       {}:
       makeSetupHook
@@ -19,8 +22,7 @@ in
           name = "remove-path-dependencies.sh";
           deps = [ ];
           substitutions = {
-            inherit pythonInterpreter;
-            yj = "${buildPackages.yj}/bin/yj";
+            pythonInterpreter = nonOverlayedPython.interpreter;
             pyprojectPatchScript = "${./pyproject-without-special-deps.py}";
             fields = [ "path" ];
             kind = "path";
@@ -29,15 +31,15 @@ in
     )
     { };
 
-  removeGitDependenciesHook = callPackage
-    ({}:
+  removeGitDependenciesHook = nonOverlayedPython.pkgs.callPackage
+    (
+      {}:
       makeSetupHook
         {
           name = "remove-git-dependencies.sh";
           deps = [ ];
           substitutions = {
-            inherit pythonInterpreter;
-            yj = "${buildPackages.yj}/bin/yj";
+            pythonInterpreter = nonOverlayedPython.interpreter;
             pyprojectPatchScript = "${./pyproject-without-special-deps.py}";
             fields = [ "git" "branch" "rev" "tag" ];
             kind = "git";
@@ -89,6 +91,4 @@ in
         } ./wheel-unpack-hook.sh
     )
     { };
-
-
 }
diff --git a/hooks/pyproject-without-special-deps.py b/hooks/pyproject-without-special-deps.py
index 9f79f9a..b74bfeb 100644
--- a/hooks/pyproject-without-special-deps.py
+++ b/hooks/pyproject-without-special-deps.py
@@ -1,13 +1,14 @@
 #!/usr/bin/env python
-# Patch out special dependencies (git and path) from a pyproject.json file
+# Patch out special dependencies (git and path) from a pyproject.toml file
 
 import argparse
-import json
 import sys
 
+import tomlkit
+
 
 def main(input, output, fields_to_remove):
-    data = json.load(input)
+    data = tomlkit.loads(input.read())
 
     try:
         deps = data["tool"]["poetry"]["dependencies"]
@@ -22,12 +23,7 @@ def main(input, output, fields_to_remove):
                 if any_removed:
                     dep["version"] = "*"
 
-    # Set ensure_ascii to False because TOML is valid UTF-8 so text that can't
-    # be represented in ASCII is perfectly legitimate
-    # HACK: Setting ensure_asscii to False breaks Python2 for some dependencies (like cachy==0.3.0)
-    json.dump(
-        data, output, separators=(",", ":"), ensure_ascii=sys.version_info.major < 3
-    )
+    output.write(tomlkit.dumps(data))
 
 
 if __name__ == "__main__":
@@ -37,20 +33,20 @@ if __name__ == "__main__":
         "--input",
         type=argparse.FileType("r"),
         default=sys.stdin,
-        help="Location from which to read input JSON",
+        help="Location from which to read input TOML",
     )
     p.add_argument(
         "-o",
         "--output",
         type=argparse.FileType("w"),
         default=sys.stdout,
-        help="Location to write output JSON",
+        help="Location to write output TOML",
     )
     p.add_argument(
         "-f",
         "--fields-to-remove",
         nargs="+",
-        help="The fields to remove from the dependency's JSON",
+        help="The fields to remove from the dependency's TOML",
     )
 
     args = p.parse_args()
diff --git a/hooks/remove-special-dependencies.sh b/hooks/remove-special-dependencies.sh
index 2d37667..a20b204 100644
--- a/hooks/remove-special-dependencies.sh
+++ b/hooks/remove-special-dependencies.sh
@@ -6,13 +6,11 @@ remove-@kind@-dependencies-hook() {
     echo "Removing @kind@ dependencies"
 
     # Tell poetry not to resolve special dependencies. Any version is fine!
-    @yj@ -tj < pyproject.toml | \
-        @pythonInterpreter@ \
-        @pyprojectPatchScript@ \
-        --fields-to-remove @fields@ > pyproject.json
-    @yj@ -jt < pyproject.json > pyproject.toml
+    @pythonInterpreter@ \
+    @pyprojectPatchScript@ \
+      --fields-to-remove @fields@ < pyproject.toml > pyproject.formatted.toml
 
-    rm pyproject.json
+    mv pyproject.formatted.toml pyproject.toml
 
     echo "Finished removing @kind@ dependencies"
 }