# \[CONSTITUTIONAL\] AIP: ArbOS Version 40 Callisto

**URL:** <https://forum.arbitrum.foundation/t/constitutional-aip-arbos-version-40-callisto/28436>\
**Category:** Finalized AIPs\
**Created:** [February 13, 2025, 1:55pm UTC](https://forum.arbitrum.foundation/t/constitutional-aip-arbos-version-40-callisto/28436 "2025-02-13T13:55:57Z")\
**Posts on this page:** 1\
**Showing post:** 51

<div class="post-metadata">

**Author:** ![Zeptimus](https://yyz1.discourse-cdn.com/flex029/user_avatar/forum.arbitrum.foundation/zeptimus/32/5471_2.png) [@Zeptimus](https://forum.arbitrum.foundation/u/Zeptimus)\
**Post date:** [May 19, 2025, 9:38pm UTC](https://forum.arbitrum.foundation/t/constitutional-aip-arbos-version-40-callisto/28436/51 "2025-05-19T21:38:33Z")

</div>

Voted YES on Tally. I believe staying aligned with Ethereum’s Pectra upgrade is crucial for Arbitrum’s growth.

Petra is running well on mainnet, and I trust the Arbitrum devs to deliver another solid implementation. Let’s do it!

---

_[View the full topic](https://forum.arbitrum.foundation/t/constitutional-aip-arbos-version-40-callisto/28436)._