> ## Documentation Index
> Fetch the complete documentation index at: https://docs.optimism.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Holocene

> Hardfork registry entry for the Holocene network upgrade, which introduced stricter derivation and dynamic EIP-1559 parameters.

<Info>
  **Normative spec:** the [Holocene specification](https://specs.optimism.io/protocol/holocene/overview.html)
  is the canonical definition of this upgrade. This page records activation data
  and operational pointers; it does not restate the spec.
</Info>

Holocene reworked derivation rules and made EIP-1559 fee parameters
configurable by chain operators.

|                                         |                                                                                                                              |
| --------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------- |
| Status                                  | Active                                                                                                                       |
| Governing spec                          | [specs.optimism.io](https://specs.optimism.io/protocol/holocene/overview.html)                                               |
| Governance approval                     | [proposal](https://vote.optimism.io/proposals/20127877429053636874064552098716749508236019236440427814457915785398876262515) |
| Operator notice                         | [View notice](/notices/archive/holocene-changes)                                                                             |
| Mainnet activation (superchain default) | Thu, 09 Jan 2025 18:00:01 UTC (`1736445601`)                                                                                 |
| Sepolia activation (superchain default) | Tue, 26 Nov 2024 15:00:00 UTC (`1732633200`)                                                                                 |

Minimum component versions (from [Holocene notice](/notices/archive/holocene-changes)):

| Component | Minimum version |
| --------- | --------------- |
| `op-node` | `v1.10.2`       |
| `op-geth` | `v1.101411.4`   |

## What changed

Per the [spec overview](https://specs.optimism.io/protocol/holocene/overview.html):

* Execution layer: [dynamic EIP-1559 parameters](https://specs.optimism.io/protocol/holocene/exec-engine.html#dynamic-eip-1559-parameters).
* Consensus layer: [Holocene derivation](https://specs.optimism.io/protocol/holocene/derivation.html#holocene-derivation).
* Smart contracts: `SystemConfig` updates.

The [Holocene notice](/notices/archive/holocene-changes) covers the operator
steps that accompanied activation, including the L1 contract upgrades.