> For the complete documentation index, see [llms.txt](https://solana-unchained.gitbook.io/whitepaper/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://solana-unchained.gitbook.io/whitepaper/technical-specifications/crypto-agility-and-post-quantum-readiness.md).

# Crypto-Agility & Post-Quantum Readiness

1\. **Current Cryptographic Baseline**

Solana wallets currently use:

* Ed25519 elliptic curve signatures for transaction signing
* SHA-256 / Keccak for address derivation and hashing
* BPF bytecode for on-chain programs

Ed25519 is not quantum-resistant. A sufficiently powerful quantum computer running Shor's algorithm could derive a private key from a known public key exposed on-chain.

2\. **Risk Tiers by Wallet State**

| Wallet State                     | Quantum Risk Level | Reason                              |
| -------------------------------- | ------------------ | ----------------------------------- |
| Created, never transacted        | Low                | Public key not yet exposed on-chain |
| Transacted at least once         | Medium-High        | Public key permanently on-chain     |
| Large balance, high-value wallet | Critical           | High incentive target               |

3\. **Unchained Wallet's Mitigation Architecture**

*Layer 1 — Social Recovery as Migration Escape Hatch*

* Pre-configured guardians can co-sign a recovery transaction to migrate assets to a new quantum-resistant keypair
* Does not require the original private key — effective even if the old key is already compromised

*Layer 2 — On-Chain Inheritance as Contingency*

* A post-quantum beneficiary address can be registered in advance
* Time-lock mechanism releases assets to the designated address if the original wallet is compromised

*Layer 3 — Planned Post-Quantum Key Support*

* Key management modules are abstracted from the signing layer
* When Solana introduces post-quantum schemes (e.g., CRYSTALS-Dilithium, SPHINCS+, XMSS), the wallet integrates them as drop-in signing modules

*Layer 4 — Proactive User Guidance*

* App notifications before any upgrade window
* One-tap "Migrate to Quantum-Safe Key" flow
* Guardian co-signatures authorize migration on-chain

4\. **Migration Flow for Pre-Upgrade Wallets**

Pre-quantum wallet (Ed25519)

        ↓

Guardian co-signs migration transaction

        ↓

New wallet generated with post-quantum keypair

        ↓

Assets transferred atomically in single transaction

        ↓

Old address marked deprecated on-chain

5\. **Residual Risks**

| Risk                                   | Status                                                                                |
| -------------------------------------- | ------------------------------------------------------------------------------------- |
| User never sets up social recovery     | Unmitigated — dependent on Solana's base layer upgrade path                           |
| Quantum computing timeline uncertainty | Estimates range 10–30 years for cryptographically relevant machines                   |
| Solana core protocol dependency        | Unchained cannot implement post-quantum signatures until Solana runtime supports them |
| Guardian collusion                     | Mitigated by M-of-N threshold requirement                                             |