diff --git a/contrib/pyln-client/pyln/client/lightning.py b/contrib/pyln-client/pyln/client/lightning.py
index 1ac25530a..096809e38 100644
--- a/contrib/pyln-client/pyln/client/lightning.py
+++ b/contrib/pyln-client/pyln/client/lightning.py
@@ -5,6 +5,21 @@ import logging
 import os
 import socket
 import warnings
+from json import JSONEncoder
+
+
+def _patched_default(self, obj):
+    return getattr(obj.__class__, "to_json", _patched_default.default)(obj)
+
+
+def monkey_patch_json(patch=True):
+    is_patched = JSONEncoder.default == _patched_default
+
+    if patch and not is_patched:
+        _patched_default.default = JSONEncoder.default  # Save unmodified
+        JSONEncoder.default = _patched_default  # Replace it.
+    elif not patch and is_patched:
+        JSONEncoder.default = _patched_default.default
 
 
 class RpcError(ValueError):
@@ -327,7 +342,10 @@ class LightningRpc(UnixDomainSocketRpc):
             return json.JSONEncoder.default(self, o)
 
     class LightningJSONDecoder(json.JSONDecoder):
-        def __init__(self, *, object_hook=None, parse_float=None, parse_int=None, parse_constant=None, strict=True, object_pairs_hook=None):
+        def __init__(self, *, object_hook=None, parse_float=None,
+                     parse_int=None, parse_constant=None,
+                     strict=True, object_pairs_hook=None,
+                     patch_json=True):
             self.object_hook_next = object_hook
             super().__init__(object_hook=self.millisatoshi_hook, parse_float=parse_float, parse_int=parse_int, parse_constant=parse_constant, strict=strict, object_pairs_hook=object_pairs_hook)
 
@@ -357,8 +375,18 @@ class LightningRpc(UnixDomainSocketRpc):
                 obj = self.object_hook_next(obj)
             return obj
 
-    def __init__(self, socket_path, executor=None, logger=logging):
-        super().__init__(socket_path, executor, logger, self.LightningJSONEncoder, self.LightningJSONDecoder())
+    def __init__(self, socket_path, executor=None, logger=logging,
+                 patch_json=True):
+        super().__init__(
+            socket_path,
+            executor,
+            logger,
+            self.LightningJSONEncoder,
+            self.LightningJSONDecoder()
+        )
+
+        if patch_json:
+            monkey_patch_json(patch=True)
 
     def autocleaninvoice(self, cycle_seconds=None, expired_by=None):
         """