stellar · kalepail · Feb 6, 2026 · Feb 2, 2026 · Feb 2, 2026 · Feb 2, 2026
diff --git a/skill/SKILL.md b/skill/SKILL.md
@@ -1,6 +1,6 @@
 ---
 name: stellar-dev
-description: End-to-end Stellar development playbook (Jan 2026). Covers Soroban smart contracts (Rust SDK), Stellar CLI, JavaScript/Python/Go SDKs for client apps, Stellar RPC (preferred) and Horizon API (legacy), Stellar Assets vs Soroban tokens (SAC bridge), wallet integration (Freighter, Stellar Wallets Kit), smart accounts with passkeys, testing strategies, security patterns, and common pitfalls. Optimized for payments, asset tokenization, DeFi, and financial applications. Use when building on Stellar, Soroban, or working with XLM, Stellar Assets, trustlines, anchors, SEPs, or the Stellar RPC/Horizon APIs.
+description: End-to-end Stellar development playbook (Jan 2026). Covers Soroban smart contracts (Rust SDK), Stellar CLI, JavaScript/Python/Go SDKs for client apps, Stellar RPC (preferred) and Horizon API (legacy), Stellar Assets vs Soroban tokens (SAC bridge), wallet integration (Freighter, Stellar Wallets Kit), smart accounts with passkeys, zero-knowledge proofs (Protocol 25 X-Ray, BN254, Poseidon), testing strategies, security patterns, and common pitfalls. Optimized for payments, asset tokenization, DeFi, privacy-preserving applications, and financial applications. Use when building on Stellar, Soroban, or working with XLM, Stellar Assets, trustlines, anchors, SEPs, ZK proofs, privacy pools, or the Stellar RPC/Horizon APIs.
 user-invocable: true
 argument-hint: "[task-description]"
 ---
@@ -15,6 +15,8 @@ Use this Skill when the user asks for:
 - Transaction building / sending / confirmation
 - Stellar Asset issuance and management
 - Client SDK usage (JavaScript, Python, Go, Rust)
+- Zero-knowledge proof verification (BN254, Poseidon, Groth16)
+- Privacy-preserving applications (privacy pools, confidential tokens)
 - Local testing and deployment
 - Security hardening and audit-style reviews
 
@@ -76,6 +78,7 @@ Use this Skill when the user asks for:
 - Need custom on-chain logic? → [contracts-soroban.md](contracts-soroban.md)
 - Building a frontend/dApp? → [frontend-stellar-sdk.md](frontend-stellar-sdk.md)
 - Issuing or managing tokens? → [stellar-assets.md](stellar-assets.md)
+- Zero-knowledge proofs or privacy? → [zk-proofs.md](zk-proofs.md)
 - Setting up tests/CI? → [testing.md](testing.md)
 - Querying chain data or indexing? → [api-rpc-horizon.md](api-rpc-horizon.md) (also see [Data Docs](https://developers.stellar.org/docs/data))
 - Security review? → [security.md](security.md)
@@ -115,6 +118,7 @@ When you implement changes, provide:
 - Frontend + wallets: [frontend-stellar-sdk.md](frontend-stellar-sdk.md)
 - Testing strategy: [testing.md](testing.md)
 - Stellar Assets: [stellar-assets.md](stellar-assets.md)
+- Zero-knowledge proofs: [zk-proofs.md](zk-proofs.md)
 - API access (RPC/Horizon): [api-rpc-horizon.md](api-rpc-horizon.md)
 - Security checklist: [security.md](security.md)
 - Common pitfalls: [common-pitfalls.md](common-pitfalls.md)
@@ -124,4 +128,6 @@ When you implement changes, provide:
 ## Keywords
 stellar, soroban, xlm, smart contracts, rust, wasm, webassembly, rpc, horizon,
 freighter, stellar-sdk, soroban-sdk, stellar-cli, trustline, anchor, sep, passkey,
-smart wallet, sac, stellar asset contract, defi, token, nft, scaffold stellar
+smart wallet, sac, stellar asset contract, defi, token, nft, scaffold stellar,
+zero-knowledge, zk, zk-snark, groth16, bn254, poseidon, pairing, privacy, confidential,
+x-ray, protocol 25, noir, risc zero, privacy pool, merkle tree
diff --git a/skill/contracts-soroban.md b/skill/contracts-soroban.md
@@ -523,3 +523,5 @@ ZK-friendly hash functions (two orders of magnitude fewer ZK constraints than SH
 - [BLS Signature](https://github.com/stellar/soroban-examples) — BLS12-381 signature verification
 
 > **Note**: BLS12-381 curve operations were added in Protocol 22 via CAP-0059. Protocol 25 adds BN254 as a complement, matching Ethereum's curve for easier migration of EVM ZK applications.
+
+> See [zk-proofs.md](zk-proofs.md) for Groth16 verification patterns, Poseidon usage, Noir/RISC Zero integration, and complete implementation guidance.
diff --git a/skill/resources.md b/skill/resources.md
@@ -109,6 +109,26 @@ For vulnerability patterns, checklists, and detailed tooling guides, see [securi
 - [CoinFabrik Audit Reports](https://www.coinfabrik.com/smart-contract-audit-reports/)
 - [Certora Security Reports](https://github.com/Certora/SecurityReports) - Includes Stellar verifications
 
+## Zero-Knowledge Proofs (Protocol 25 X-Ray)
+
+For comprehensive ZK development guidance, see [zk-proofs.md](zk-proofs.md).
+
+### Protocol & Specifications
+- [X-Ray Announcement](https://stellar.org/blog/developers/announcing-stellar-x-ray-protocol-25) - Protocol 25 overview
+- [CAP-0074](https://github.com/stellar/stellar-protocol/blob/master/core/cap-0074.md) - BN254 elliptic curve specification
+- [CAP-0075](https://github.com/stellar/stellar-protocol/blob/master/core/cap-0075.md) - Poseidon hash function specification
+
+### SDK Documentation
+- [Soroban SDK BN254](https://docs.rs/soroban-sdk/latest/soroban_sdk/crypto/bn254/) - BN254 types and functions
+- [Soroban SDK Crypto](https://docs.rs/soroban-sdk/latest/soroban_sdk/crypto/) - Full crypto module reference
+
+### Proving Systems & Tooling
+- [Noir Documentation](https://noir-lang.org/docs/) - Aztec's ZK domain-specific language
+- [RISC Zero](https://dev.risczero.com/) - General-purpose zkVM for Rust programs
+
+### Example Contracts
+- [Soroban Examples](https://github.com/stellar/soroban-examples) - Official examples (includes `groth16_verifier`, `privacy-pools`, `import_ark_bn254`)
- [Soroban Examples](https://github.com/stellar/soroban-examples) - Official examples (includes `groth16_verifier`, `privacy-pools`, `import_ark_bn254`)
+- [Soroban Examples](https://github.com/stellar/soroban-examples) - Official examples (e.g., `groth16_verifier`, `import_ark_bn254`)
- [Soroban Examples](https://github.com/stellar/soroban-examples) - Official examples (includes `groth16_verifier`, `privacy-pools`, `import_ark_bn254`)
+- [Soroban Examples](https://github.com/stellar/soroban-examples) - Official examples (e.g., `groth16_verifier`, `import_ark_bn254`)
+
 ## Testing
 
 ### Testing Guides
Original file line number	Diff line number	Diff line change
Expand Up		@@ -523,3 +523,5 @@ ZK-friendly hash functions (two orders of magnitude fewer ZK constraints than SH
		- [BLS Signature](https://github.com/stellar/soroban-examples) — BLS12-381 signature verification

		> Note: BLS12-381 curve operations were added in Protocol 22 via CAP-0059. Protocol 25 adds BN254 as a complement, matching Ethereum's curve for easier migration of EVM ZK applications.

		> See [zk-proofs.md](zk-proofs.md) for Groth16 verification patterns, Poseidon usage, Noir/RISC Zero integration, and complete implementation guidance.
Copilot AI Feb 2, 2026 Copy link Choose a reason for hiding this comment The reason will be displayed to describe this comment to others. Learn more. The reference to zk-proofs.md is helpful, but the BN254 API examples shown earlier in this section (lines 495-508) use a different API style than what's documented in zk-proofs.md. The old examples use method calls like `bn254.g1_add()` while zk-proofs.md uses operator overloading like `G1Affine + G1Affine`. Similarly, the Poseidon description at line 512 mentions `env.crypto_hazmat()` with a `hazmat` feature flag, while zk-proofs.md shows `env.crypto().poseidon_hash()`. Consider either updating the earlier examples in this section to match zk-proofs.md's API, or removing them entirely to avoid confusion since comprehensive guidance is now in the dedicated file. Copilot uses AI. Check for mistakes.