Protocol 26 (Yardstick): Stellar's Next Major Upgrade Goes Live on Testnet

On April 16, 2026, the Stellar Development Foundation (SDF) launched the testnet for Protocol 26, codenamed "Yardstick." This upgrade represents a significant step forward in Stellar's capabilities, with a mainnet validator vote scheduled for May 2026.

What Is Protocol 26 (Yardstick)?

Protocol 26 is the next major upgrade to the Stellar network, building on the foundation laid by Protocol 21 (Soroban launch) and subsequent improvements. The "Yardstick" codename reflects its focus on establishing new benchmarks for network performance and capability.

Key Changes in Protocol 26

1. Enhanced Transaction Throughput

Yardstick introduces optimizations to the Stellar Consensus Protocol (SCP) that enable higher transaction throughput. The target is to support sustained 5,000+ TPS under production conditions, up from the current practical limit of approximately 1,000 TPS.

Key improvements include:

Parallel ledger close processing: Multiple ledger components can now be finalized simultaneously

Optimized nomination rounds: Reduced consensus overhead for faster agreement

Batch transaction validation: Groups of transactions validated together for efficiency

2. Soroban VM Improvements

The Soroban smart contract runtime receives several enhancements:

Increased compute budget: Smart contracts can perform more complex operations per invocation

Memory optimizations: Reduced memory overhead for contract execution

New host functions: Additional built-in functions for common operations (hashing, cryptographic verification)

Improved state archival: More efficient handling of archived contract state

3. Network Fee Refinements

Protocol 26 introduces a more dynamic fee model:

Surge pricing improvements: Smoother fee scaling during high-demand periods

Fee estimation API: New RPC method for accurate fee prediction

Resource-based pricing: Fees more closely reflect actual computational resources consumed

4. Cross-Chain Interoperability Primitives

New protocol-level features to support cross-chain communication:

Hash time-locked contracts (HTLCs) at the protocol level for atomic swaps

Standardized bridge message format for interoperability protocols

Merkle proof verification as a native operation

Testnet Timeline

Milestone	Date	Status
Testnet Launch	April 16, 2026	Active
Developer Preview	April 21, 2026	Upcoming
Public Testing Period	April 21 - May 10, 2026	Upcoming
Validator Vote	May 2026	Scheduled
Mainnet Activation	May/June 2026	Pending Vote

What Developers Should Do

1. Test Your Applications

If you have applications running on Stellar, test them against the Protocol 26 testnet. Focus on:

Transaction submission and fee estimation

Soroban contract interactions

Any custom logic that depends on protocol-specific behavior

2. Update Your SDKs

The Stellar SDK team will release updated versions of all official SDKs (JavaScript, Go, Python, Java) with Protocol 26 support. Update early to take advantage of new features.

3. Review New Host Functions

If you're building Soroban contracts, review the new host functions available in Protocol 26. These can simplify your contract code and reduce gas costs.

How to Connect to the Testnet

You can connect to the Protocol 26 testnet using:

# Horizon API (testnet)
curl https://horizon-testnet.stellar.org/ledgers?limit=1

# Soroban RPC (testnet)
curl -X POST https://soroban-testnet.stellar.org \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","id":1,"method":"getHealth"}'

Impact on LumenQuery

LumenQuery will fully support Protocol 26 features as they become available on mainnet. Our Horizon API and Soroban RPC endpoints will be updated to handle new transaction types, fee models, and host functions. No action is required from LumenQuery users; the transition will be seamless.

Stay informed about Protocol 26 progress through our analytics dashboard and documentation at lumenquery.io/docs.