diff --git a/confutils/envvar/writer.nim b/confutils/envvar/writer.nim
index 36c5a7f..2b160e1 100644
--- a/confutils/envvar/writer.nim
+++ b/confutils/envvar/writer.nim
@@ -21,7 +21,7 @@ proc writeValue*(w: var EnvvarWriter, value: auto) =
   elif value is (SomePrimitives or range):
     let key = constructKey(w.prefix, w.key)
     setValue(key, value)
-  
+
   elif value is Option:
     if value.isSome:
       w.writeValue value.get
diff --git a/tests/test_config_file.nim b/tests/test_config_file.nim
index 6f9ef26..ad586f3 100644
--- a/tests/test_config_file.nim
+++ b/tests/test_config_file.nim
@@ -149,13 +149,19 @@ proc readValue(r: var TomlReader,
   value = T r.parseAsString()
 
 proc readValue(r: var TomlReader, value: var ValidIpAddress) =
-  value = ValidIpAddress.init(r.parseAsString())
+  try:
+    value = ValidIpAddress.init(r.parseAsString())
+  except ValueError as ex:
+    raise newException(SerializationError, ex.msg)
 
 proc readValue(r: var TomlReader, value: var Port) =
   value = r.parseInt(int).Port
 
 proc readValue(r: var TomlReader, value: var GraffitiBytes) =
-  value = hexToByteArray[value.len](r.parseAsString())
+  try:
+    value = hexToByteArray[value.len](r.parseAsString())
+  except ValueError as ex:
+    raise newException(SerializationError, ex.msg)
 
 proc readValue(r: var EnvvarReader,
   value: var (InputFile | InputDir | OutFile | OutDir | ValidatorKeyPath)) =