> ## Documentation Index
> Fetch the complete documentation index at: https://docs.x0protocol.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Resources

> External documentation, references, and academic papers relevant to the x0 protocol.

## Solana

<CardGroup cols={2}>
  <Card title="Solana Documentation" icon="book" href="https://solana.com/docs">
    Official Solana developer documentation covering accounts, transactions, and programs.
  </Card>

  <Card title="Solana Cookbook" icon="utensils" href="https://solanacookbook.com">
    Practical recipes and patterns for Solana development.
  </Card>

  <Card title="Solana Program Library" icon="cube" href="https://spl.solana.com">
    SPL token programs, governance, and standard libraries.
  </Card>

  <Card title="Solana Explorer" icon="magnifying-glass" href="https://explorer.solana.com">
    On-chain transaction and account explorer.
  </Card>
</CardGroup>

## Token-2022

<CardGroup cols={2}>
  <Card title="Token-2022 Documentation" icon="coins" href="https://spl.solana.com/token-2022">
    SPL Token-2022 program with extension architecture.
  </Card>

  <Card title="Transfer Hook Guide" icon="hook" href="https://solana.com/developers/guides/token-extensions/transfer-hook">
    How to implement transfer hooks for custom validation logic.
  </Card>

  <Card title="Transfer Fee Extension" icon="percent" href="https://solana.com/developers/guides/token-extensions/transfer-fee">
    Automatic fee collection on every token transfer.
  </Card>

  <Card title="Confidential Transfers" icon="eye-slash" href="https://solana.com/developers/guides/token-extensions/confidential-transfer">
    ElGamal-encrypted token balances and transfers.
  </Card>
</CardGroup>

## Anchor Framework

<CardGroup cols={2}>
  <Card title="Anchor Documentation" icon="anchor" href="https://www.anchor-lang.com">
    Solana's Anchor framework for building on-chain programs.
  </Card>

  <Card title="Anchor Book" icon="book-open" href="https://book.anchor-lang.com">
    Comprehensive guide to Anchor program development.
  </Card>
</CardGroup>

## Cryptography

### Zero-Knowledge Proofs

| Resource                                          | Description                                                                                                                   |
| ------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------- |
| [Groth16 Paper](https://eprint.iacr.org/2016/260) | Jens Groth, "On the Size of Pairing-Based Non-interactive Arguments" (EUROCRYPT 2016) — the proof system used in x0-zk-proofs |
| [ZK Proof Standards](https://zkproof.org)         | Community standards for zero-knowledge proofs                                                                                 |

### ElGamal Encryption

| Resource                                                                   | Description                                                                          |
| -------------------------------------------------------------------------- | ------------------------------------------------------------------------------------ |
| [Ristretto Group](https://ristretto.group)                                 | The Ristretto group used for ElGamal encryption in Token-2022 confidential transfers |
| [curve25519-dalek](https://github.com/dalek-cryptography/curve25519-dalek) | Rust implementation of elliptic curve operations used by solana-zk-sdk               |
| [solana-zk-sdk](https://docs.rs/solana-zk-sdk/latest/solana_zk_sdk/)       | Solana's ZK proof SDK for confidential transfers                                     |

### Merkle Trees & Bloom Filters

| Resource                                                               | Description                                                              |
| ---------------------------------------------------------------------- | ------------------------------------------------------------------------ |
| [Merkle Tree (Wikipedia)](https://en.wikipedia.org/wiki/Merkle_tree)   | Hash tree structure used for efficient whitelist verification            |
| [Bloom Filter (Wikipedia)](https://en.wikipedia.org/wiki/Bloom_filter) | Probabilistic data structure used for space-efficient whitelist checking |

## Solana Actions (Blinks)

<CardGroup cols={2}>
  <Card title="Solana Actions Specification" icon="link" href="https://solana.com/docs/advanced/actions">
    Official specification for Solana Actions (Blinks).
  </Card>

  <Card title="Dialect Blinks" icon="comment" href="https://dialect.to">
    Blink client and tooling for Solana Actions.
  </Card>
</CardGroup>

## x0 Protocol

<CardGroup cols={2}>
  <Card title="GitHub Repository" icon="github" href="https://github.com/x0-01/x0-01">
    Full source code — on-chain programs, SDK, and documentation.
  </Card>

  <Card title="Whitepaper (PDF)" icon="file-pdf" href="https://github.com/x0-01/x0-01/blob/main/whitepaper.pdf">
    40-page technical specification covering architecture, cryptography, and economics.
  </Card>
</CardGroup>

## Development Tools

| Tool                                                        | Description                                        |
| ----------------------------------------------------------- | -------------------------------------------------- |
| [Solana CLI](https://docs.solanalabs.com/cli/install)       | Command-line tools for Solana development          |
| [Anchor CLI](https://www.anchor-lang.com/docs/installation) | Build, test, and deploy Anchor programs            |
| [wasm-pack](https://rustwasm.github.io/wasm-pack/)          | Build Rust-to-WASM packages (used by x0-zk-proofs) |
| [Solana Playground](https://beta.solpg.io)                  | Browser-based Solana IDE                           |