# v3.10.3

Released on 2021-10-08.

Fixes more regressions from 3.10.0. All changes are backward-compatible.

- Fixes [extended-diagnostics](../../api/macros/json_diagnostics.md) assertions triggered by
  [`update`](../../api/basic_json/update.md) and by inserting into arrays.
- Supports custom allocators when writing binary formats into a `std::vector`, and allows conversion
  from types that only provide `begin()`/`end()`.

[Full release notes](https://github.com/nlohmann/json/releases/tag/v3.10.3).

## API changes

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