Issues

• [Bug] Negative POSIX timestamps cannot be deserialized after timestamp serialization

  marshmallow-code/marshmallow#3019 · Filter by author Sohel2309 opened on Aug 13, 2026
  2

• Inconsistent value type when validating nested schema fields

  marshmallow-code/marshmallow#2961 · Filter by author torotil opened on Apr 27, 2026
  4

• Dependency Dashboard

  marshmallow-code/marshmallow#2953 · Filter by author renovate opened on Apr 13, 2026

• Feature - allow inheriting load_default from nested schema populated with from_dict

  marshmallow-code/marshmallow#2889 · Filter by author nneul opened on Jan 6, 2026
  2

• Consistency with allow_none with serialization and deserialization

  marshmallow-code/marshmallow#2836 · Filter by author matejsp opened on Jul 16, 2025
  1

• SchemaOpts misses partial

  marshmallow-code/marshmallow#2834 · Filter by author number492 opened on Jun 24, 2025

• 'NoneType' object is not subscriptable when serializing fields that do not belong to the database is None

  question
  marshmallow-code/marshmallow#2833 · Filter by author dinghao-8 opened on Jun 20, 2025
  3

• Removing Schema context feels like a bad idea!

  marshmallow-code/marshmallow#2832 · Filter by author ThiefMaster opened on Jun 20, 2025
  3

• Is there a way to pre-define built-in validators that can be used multiple times?

  question
  marshmallow-code/marshmallow#2829 · Filter by author herkalurk opened on Jun 3, 2025
  2

• Extra documentation for new context implementation?

  polymorphismquestion
  marshmallow-code/marshmallow#2824 · Filter by author RosanneZe opened on Apr 24, 2025
  21

• TimeDelta misleading 'precision' argument & v4 breaking change

  feedback welcome
  marshmallow-code/marshmallow#2822 · Filter by author OJFord opened on Apr 21, 2025
  3

• Dump converts int or bool to float

  polymorphism
  marshmallow-code/marshmallow#2816 · Filter by author Oriel-Barroso opened on Mar 31, 2025
  1

• Remove only, exclude, many, and unknown parameters of Nested and require callables to return Schema instances

  backwards incompatfeedback welcome
  marshmallow-code/marshmallow#2794 · Filter by author sloria opened on Jan 19, 2025
  1

• fields.URL validation error should specify "not a valid FQDN" if trying to pass hostname without domain

  Feature

  marshmallow-code/marshmallow#2243 · Filter by author ff137 opened on Feb 20, 2024
  2

• Dot in key is not parsed correclty on loads()

  docs
  marshmallow-code/marshmallow#2194 · Filter by author dchirikov opened on Oct 5, 2023
  3

• [RFC] Add BigInt, SmallInt,... fields.

  marshmallow-code/marshmallow#2182 · Filter by author lafrech opened on Sep 11, 2023
  3

• Are nested options applied correctly?

  marshmallow-code/marshmallow#2180 · Filter by author matuqam opened on Sep 1, 2023
  1

• Doubly Nested Schemas instantiated via lambdas cannot be referenced with multiple dot notation with onlys/excludes

  Bug

  marshmallow-code/marshmallow#2165 · Filter by author somethingnew2-0 opened on Aug 11, 2023
  3

• Allow 'load_default' for required fields since they can be used with partial.

  marshmallow-code/marshmallow#2151 · Filter by author matejsp opened on Jul 19, 2023
  3

• Add ability to set partial default in Meta class

  Feature

  marshmallow-code/marshmallow#2103 · Filter by author npalmius opened on Feb 17, 2023
  2

• Emit warning when user passes string instead of list to OneOf

  Feature

  marshmallow-code/marshmallow#2074 · Filter by author lafrech opened on Nov 25, 2022
  1

• Include a nested relation to one schema, without modifying the rest of the functions that use it

  marshmallow-code/marshmallow#2069 · Filter by author abdielcs opened on Nov 10, 2022
  2

• Allow_none in additional parameters

  question
  marshmallow-code/marshmallow#2043 · Filter by author RedekG opened on Sep 1, 2022
  1

• Bug: several nested partial issues (sequence partial, data key, schema initialized partial)

  Bug

  marshmallow-code/marshmallow#2041 · Filter by author pavellos21 opened on Aug 31, 2022
  8

• [RFC] Don't pass attr, obj, data to fields (de)serialize methods

  backwards incompatfeedback welcome
  marshmallow-code/marshmallow#2039 · Filter by author lafrech opened on Aug 25, 2022 · 5.0
  8