Ethereum Staking Deposit Contract Could Be Updated for Future Key Formats

Ethereum’s core developers have opened a draft proposal that would modify the staking deposit contract to support future credential formats, including quantum‑resistant keys, and to provide a one‑way switch that could permanently retire the existing BLS12‑381 key format.

How the proposal changes the deposit contract

The current deposit contract only accepts public keys and signatures in a fixed BLS12‑381 format. The draft adds a scheme identifier and variable‑length fields for the public key and optional metadata, each limited to 8,192 bytes. When a deposit is made, the execution layer records the data while the consensus layer validates the credential before creating or updating a validator.

Three operational modes

• Disabled: No deposits are accepted.
• BLS enabled: Deposits using the existing BLS format are accepted.
• BLS retired: New BLS deposits are rejected; the contract only accepts non‑BLS credentials as opaque data.

Transitions between these modes are irreversible; once the contract enters the retired mode, BLS onboarding cannot be re‑enabled.

What remains to be defined

While the draft outlines how the contract would handle new key formats, separate specifications are still required for signature verification, validator state representation, top‑ups, duplicate handling, uniqueness checks, and key replacement. Implementing the changes would also need a coordinated fork of both the execution and consensus layers.

Post‑quantum roadmap context

Ethereum’s longer‑term plan pairs a hash‑based signature scheme (leanXMSS) with leanVM to aggregate larger post‑quantum signatures efficiently. The network targets around 2029 for a quantum‑resistant migration, though no quantum computer currently threatens Ethereum’s cryptography.

Current status

The proposal was opened as pull request #12235 on August 24 and remained an unmerged draft as of August 26. It has not been assigned an official EIP number, though an editor suggested EIP‑8394.