# Ic-py Development and Ongoing Maintenance

**URL:** <https://forum.dfinity.org/t/ic-py-development-and-ongoing-maintenance/47455>\
**Category:** Developers\
**Tags:** Discussing, agent\
**Created:** [May 8, 2025, 8:54am UTC](https://forum.dfinity.org/t/ic-py-development-and-ongoing-maintenance/47455 "2025-05-08T08:54:35Z")\
**Posts on this page:** 2\
**Page:** 5

<div class="post-metadata">

**Author:** ![C-B-Elite](https://sea1.discourse-cdn.com/flex023/user_avatar/forum.dfinity.org/c-b-elite/32/34356_2.png) [@C-B-Elite](https://forum.dfinity.org/u/C-B-Elite)\
**Post date:** [May 12, 2026, 9:38am UTC](https://forum.dfinity.org/t/ic-py-development-and-ongoing-maintenance/47455/81 "2026-05-12T09:38:30Z")

</div>

Sorry, I just returned from a long trip. I’ll look into this issue and fix it over the next couple of days, and then I’ll release a new version shortly afterward. Thanks for pointing out the issue.

---

<div class="post-metadata">

**Author:** ![C-B-Elite](https://sea1.discourse-cdn.com/flex023/user_avatar/forum.dfinity.org/c-b-elite/32/34356_2.png) [@C-B-Elite](https://forum.dfinity.org/u/C-B-Elite)\
**Post date:** [May 13, 2026, 10:23am UTC](https://forum.dfinity.org/t/ic-py-development-and-ongoing-maintenance/47455/82 "2026-05-13T10:23:29Z")

</div>

# icp-py-core v2.3.1 Released

I have released **icp-py-core v2.3.1** with bug fixes for IC spec compliance and new ECDSA P-256 (secp256r1) support. Upgrade with:

```bash
pip install --upgrade icp-py-core

```

This is a drop-in upgrade — no API changes; existing code continues to work.

* * *

## New features

**ECDSA P-256 (secp256r1) identity**

`Identity` now supports P-256 alongside Ed25519 and secp256k1. Useful for WebAuthn / passkey integrations.

```python
from icp_identity.identity import Identity

iden = Identity(type="p256") # or "secp256r1"

```

* * *

## Bug fixes

These are silent correctness issues — your code didn’t change, but it now behaves correctly per the IC interface spec.

**`reject_code` now reports the real value**

Previously, update calls rejected via the polling / async path silently reported `reject_code = 0`. You now get the actual reject code (e.g. `5` for  
`CANISTER_REJECT`).

**`Principal.from_str` is case-insensitive**

`Principal.from_str("AAAAA-AA")` and `"aaaaa-aa"` both work now, per spec.

**`Principal.self_authenticating` accepts more key types**

Previously rejected valid BLS subnet keys (including the IC root key) and P-256 keys. Now accepts any well-formed DER public key.

**`update_raw_async` uses the v4 synchronous response**

The async path was always polling, even when `/call` returned the result inline. Now matches the sync fast path — one fewer round-trip in the common case.

**Request ID encoding fix**

`to_request_id` was using Signed LEB128 for natural numbers instead of Unsigned LEB128 as the spec mandates. Latent bug fixed before it could bite.

**cbor2 6.x compatibility**

Closes [#14](https://github.com/eliezhao/icp-py-core/issues/14). cbor2 6.0+ returns `frozendict` for tagged maps; the library now accepts both `dict` (5.x) and  
`frozendict` (6.x). You can use the latest cbor2 without pinning.  
@marc0olo @icpp

**Candid `composite_query` round-trip**

Loading a DID file that declares `composite_query` methods now works end-to-end.

* * *

## Links

- **PyPI:** [icp-py-core · PyPI](https://pypi.org/project/icp-py-core/)
- **Repo & changelog:** [GitHub - eliezhao/icp-py-core: Python Agent Library for the DFINITY Internet Computer · GitHub](https://github.com/eliezhao/icp-py-core)
- **Release notes:** [Release v2.3.1 — Candid spec compliance · eliezhao/icp-py-core · GitHub](https://github.com/eliezhao/icp-py-core/releases/tag/v2.3.1)

[Previous page](https://forum.dfinity.org/t/ic-py-development-and-ongoing-maintenance/47455.md?page=4)