diff --git a/cashu/core/base.py b/cashu/core/base.py
index 6fa9fe9..63d7f5c 100644
--- a/cashu/core/base.py
+++ b/cashu/core/base.py
@@ -1,5 +1,5 @@
 from sqlite3 import Row
-from typing import List
+from typing import List, Union
 
 from pydantic import BaseModel
 
@@ -12,7 +12,7 @@ class CashuError(BaseModel):
 class P2SHScript(BaseModel):
     script: str
     signature: str
-    address: str = None
+    address: Union[str, None] = None
 
     @classmethod
     def from_row(cls, row: Row):
@@ -28,7 +28,7 @@ class Proof(BaseModel):
     amount: int
     secret: str = ""
     C: str
-    script: P2SHScript = None
+    script: Union[P2SHScript, None] = None
     reserved: bool = False  # whether this proof is reserved for sending
     send_id: str = ""  # unique ID of send attempt
     time_created: str = ""
@@ -121,15 +121,17 @@ class GetMintResponse(BaseModel):
 
 
 class GetMeltResponse(BaseModel):
-    paid: str
-    preimage: str
+    paid: Union[bool, None]
+    preimage: Union[str, None]
 
 
 class SplitRequest(BaseModel):
     proofs: List[Proof]
     amount: int
-    output_data: MintRequest = None  # backwards compatibility with clients < v0.2.2
-    outputs: MintRequest = None
+    output_data: Union[
+        MintRequest, None
+    ] = None  # backwards compatibility with clients < v0.2.2
+    outputs: Union[MintRequest, None] = None
 
     def __init__(self, **data):
         super().__init__(**data)
diff --git a/cashu/core/settings.py b/cashu/core/settings.py
index 99aa9a7..e328d3e 100644
--- a/cashu/core/settings.py
+++ b/cashu/core/settings.py
@@ -1,13 +1,13 @@
 import os
 import sys
 from pathlib import Path
+from typing import Union
 
 from environs import Env  # type: ignore
-from loguru import logger
 
 env = Env()
 
-ENV_FILE = os.path.join(str(Path.home()), ".cashu", ".env")
+ENV_FILE: Union[str, None] = os.path.join(str(Path.home()), ".cashu", ".env")
 if not os.path.isfile(ENV_FILE):
     ENV_FILE = os.path.join(os.getcwd(), ".env")
 if os.path.isfile(ENV_FILE):
diff --git a/cashu/mint/router.py b/cashu/mint/router.py
index ad70992..bb91695 100644
--- a/cashu/mint/router.py
+++ b/cashu/mint/router.py
@@ -80,7 +80,7 @@ async def split(payload: SplitRequest):
     """
     proofs = payload.proofs
     amount = payload.amount
-    outputs = payload.outputs.blinded_messages
+    outputs = payload.outputs.blinded_messages if payload.outputs else None
     try:
         split_return = await ledger.split(proofs, amount, outputs)
     except Exception as exc: