feat: add ZK examples (zk-id, zk-nullifier, zk-merkle-proof)

- Move zk-id from root to zk/ folder
- Add zk-nullifier: single and batch (4x) nullifier creation with Groth16
- Add zk-merkle-proof: merkle proof verification with compressed accounts
- Update CI to test zk/zk-id, zk/zk-nullifier, zk/zk-merkle-proof

Author: tilo-14

.github/workflows/rust-tests.yml

@@ -29,7 +29,9 @@ jobs:
           - counter/native
           - counter/pinocchio
           - account-comparison
-          - zk-id
+          - zk/zk-id
+          - zk/zk-nullifier
+          - zk/zk-merkle-proof
           - airdrop-implementations/simple-claim/program
         include:
           - example: basic-operations/native
@@ -51,10 +53,10 @@ jobs:
           example: ${{ matrix.example }}
           solana-cli-version: ${{ env.SOLANA_CLI_VERSION }}
           rust-toolchain: ${{ env.RUST_TOOLCHAIN }}
-          install-circom: ${{ matrix.example == 'zk-id' }}
+          install-circom: ${{ startsWith(matrix.example, 'zk/') || startsWith(matrix.example, 'zk/') }}
 
       - name: Setup ZK circuits
-        if: matrix.example == 'zk-id'
+        if: startsWith(matrix.example, 'zk/') || startsWith(matrix.example, 'zk/')
         working-directory: ${{ matrix.example }}
         run: ./scripts/setup.sh
 

README.md

@@ -12,16 +12,18 @@
 For simple client side distribution visit [this example](https://github.com/Lightprotocol/example-token-distribution).
 
 ### Basic Operations
-- **[create-nullifier](./basic-operations/anchor/create-nullifier)** - Basic Anchor example to create nullifiers.
-- **[basic-operations/anchor](./basic-operations/anchor/)** - Anchor program with Rust and TypeScript tests
-- **[basic-operations/native-rust](./basic-operations/native-rust/)** - Native Solana program with light-sdk and Rust tests.
 
-Basic Operations include:
-- **create** - Initialize a new compressed account.
-- **update** - Modify data in an existing compressed account.
-- **close** - Clear account data and preserve its address.
-- **reinit** - Reinitialize a closed account with the same address.
-- **burn** - Permanently delete a compressed account.
+- **[create-nullifier](./basic-operations/anchor/create-nullifier)** - Basic Anchor example to create nullifiers for payments.
+- **create** - Initialize a new compressed account
+  - [Anchor](./basic-operations/anchor/create) | [Native](./basic-operations/native/programs/create)
+- **update** - Modify data in an existing compressed account
+  - [Anchor](./basic-operations/anchor/update) | [Native](./basic-operations/native/programs/update)
+- **close** - Clear account data and preserve its address
+  - [Anchor](./basic-operations/anchor/close) | [Native](./basic-operations/native/programs/close)
+- **reinit** - Reinitialize a closed account with the same address
+  - [Anchor](./basic-operations/anchor/reinit) | [Native](./basic-operations/native/programs/reinit)
+- **burn** - Permanently delete a compressed account
+  - [Anchor](./basic-operations/anchor/burn) | [Native](./basic-operations/native/programs/burn)
 
 ### Counter Program
 
@@ -45,9 +47,17 @@ Full compressed account lifecycle (create, increment, decrement, reset, close):
 
 - **[account-comparison](./account-comparison/)** - Compare compressed vs regular Solana accounts.
 
-### zk-id Program
+### ZK Programs
 
-- **[zk-id](./zk-id)** - A minimal zk id Solana program that uses zero-knowledge proofs for identity verification with compressed accounts.
+**Full Examples:**
+
+- **[zk-id](./zk/zk-id)** - Identity verification using Groth16 proofs. Issuers create credentials; users prove ownership without revealing the credential.
+- **[shielded-pool](./zk/shielded-pool)** - Privacy-preserving deposit/withdrawal .
+
+**Basic Examples:**
+
+- **[zk-nullifier](./zk/zk-nullifier)** - Creates one or four nullifiers. Uses Groth16 proofs and compressed accounts.
+- **[zk-merkle-proof](./zk/zk-merkle-proof)** - Creates compressed accounts and verifies with Groth16 proofs (without nullifier).
 
 
 ## Light Protocol dependencies

zk/README.md

@@ -0,0 +1,21 @@
+# ZK Examples
+
+Building a private Solana program requires a Merkle tree to store state, a way to track nullifiers, and an indexer to serve Merkle proofs.
+
+You can use Light to:
+- Track and store nullifiers rent-free in indexed address Merkle trees
+- Store state rent-free in indexed state Merkle trees as compressed accounts
+
+[Learn more in the documentation](https://www.zkcompression.com/zk/overview)
+
+## Examples
+
+**Full Examples:**
+
+- **[zk-id](./zk/zk-id)** - Identity verification using Groth16 proofs. Issuers create credentials; users prove ownership without revealing the credential.
+- **[shielded-pool](./zk/shielded-pool)** - Privacy-preserving deposit/withdrawal .
+
+**Basic Examples:**
+
+- **[zk-nullifier](./zk/zk-nullifier)** - Creates one or four nullifiers. Uses Groth16 proofs and compressed accounts.
+- **[zk-merkle-proof](./zk/zk-merkle-proof)** - Creates compressed accounts and verifies with Groth16 proofs (without nullifier).

zk-id/.gitignore zk/zk-id/.gitignorezk-id/.gitignore renamed to zk/zk-id/.gitignore

@@ -0,0 +1,23 @@
+[toolchain]
+anchor_version = "0.31.1"
+
+[features]
+resolution = true
+skip-lint = false
+
+[workspace]
+members = ["."]
+
+[programs.localnet]
+zk_id = "HNqStLMpNuNJqhBF1FbGTKHEFbBLJmq8RdJJmZKWz6jH"
+
+[registry]
+url = "https://api.apr.dev"
+
+[provider]
+cluster = "localnet"
+wallet = "~/.config/solana/id.json"
+
+[scripts]
+test = "yarn run ts-mocha -p ./tsconfig.json -t 1000000 tests/**/*.ts"
+

zk/zk-id/Anchor.toml

@@ -37,3 +37,6 @@ groth16-solana = { git = "https://github.com/Lightprotocol/groth16-solana", feat
 [target.'cfg(not(target_os = "solana"))'.build-dependencies]
 rust-witness = "0.1"
 groth16-solana = { git = "https://github.com/Lightprotocol/groth16-solana", features = ["vk"], rev = "66c0dc87d0808c4d2aadb53c61435b6edb8ddfd9" }
+
+[profile.release]
+overflow-checks = true

zk-id/CLAUDE.md zk/zk-id/CLAUDE.mdzk-id/CLAUDE.md renamed to zk/zk-id/CLAUDE.md

@@ -67,14 +67,22 @@ This script will:
 
 ## Build and Test
 
+**Build:**
 ```bash
-# Build the program
 cargo build-sbf
+```
 
-# Run tests and see tx
+**Rust tests** (full ZK verification flow):
+```bash
 RUST_BACKTRACE=1 cargo test-sbf -- --nocapture
 ```
 
+**TypeScript tests** (requires local validator with Light Protocol):
+```bash
+npm install
+npm test
+```
+
 ## Structure
 
 ```
@@ -89,7 +97,8 @@ zk-id/
 ├── src/
 │   └── lib.rs             # Solana program implementation
 └── tests/
-    └── test.rs            # Integration tests
+    ├── test.rs            # Rust integration tests
+    └── zk-id.ts           # TypeScript integration tests
 ```
 
 ## Cleaning Build Artifacts