# Dev Update 28 September 2026

**URL:** <https://talk.neptune.cash/t/dev-update-28-september-2026/399>\
**Category:** News and Announcements\
**Created:** [September 28, 2026, 7:51pm UTC](https://talk.neptune.cash/t/dev-update-28-september-2026/399 "2026-09-28T19:51:02Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![aszepieniec](https://talk.neptune.cash/user_avatar/talk.neptune.cash/aszepieniec/32/5_2.png) [@aszepieniec](https://talk.neptune.cash/u/aszepieniec)\
**Post date:** [September 28, 2026, 7:51pm UTC](https://talk.neptune.cash/t/dev-update-28-september-2026/399/1 "2026-09-28T19:51:02Z")

</div>

# Dev Update

## 1. Last Week by the Numbers

### [neptune-core](https://github.com/Neptune-Crypto/neptune-core)

- Pull Requests: 1 opened, 2 merged
- Commits: 13 merged into master

### [triton-vm](https://github.com/TritonVM/triton-vm)

- Pull Requests: 1 opened, 0 merged

### [twenty-first](https://github.com/Neptune-Crypto/twenty-first)

- Pull Requests: 1 opened, 0 merged

## 2. Stand-up Summary

### Alan Szepieniec

- **Last Week:** Analyzed trade-offs of succinctness scaling proposals (including nullifier sets and UTXO membership proofs); and refined the smart contract plug-in architecture to favor an online subscriber mechanism over CLI callback scripts.
- **Coming Week:** Implement a thread registration mechanism within Neptune Core to facilitate smart contract event loops while ensuring the design remains generalizable.

### Thorkil Værge

- **Last Week:** Addressed peer-to-peer DHT warning messages using hardcoded nodes; separated networking and chain data state locks to enable concurrent networking tasks during block processing; optimized succinctness metrics down to 110,000 AET rows per input; and outlined design proposals for transaction input scaling (witness data removal, VM sparse Merkle tree chunk hashes, and nullifier sets).
- **Coming Week:** Develop an RPC endpoint to define the block composition state for future Neptune contracts, and manage node versioning by keeping one hardcoded node on an older software version during the DHT upgrade.

## 3. Technical Discussion

- **Networking & State Lock Separation:** Addressed peer-to-peer connection warnings by updating distributed hash tables with hardcoded nodes to prevent consensus-level splits. Separated global state locks into distinct locks for networking and chain data, enabling networking tasks to run concurrently while processing blocks.
- **Succinctness & Transaction Input Scaling:** Proving micro-optimizations and active input index updates brought metrics down to 110,000 AET rows per input. Confirmed that succinctness cannot be achieved via a soft fork, making a hard fork necessary. Evaluated several design options for scaling transaction input capacity:
  - Removing witness data from blocks (reduces proving complexity by a factor of 4.5 and size per input by a factor of 2, requiring an archival mutator set), with an option kept open to store witness data in an extra block.
  - Updating chunk hash definitions to use a sparse Merkle tree inside the virtual machine.
  - Replacing the sliding window bloom filter with a nullifier set, noting the trade-off of losing free membership proofs for unspent transaction outputs (UTXOs) and requiring retrieval from an archival data structure.

- **Smart Contract Architecture:** Refined the smart contract plug-in interface to ensure Neptune Core remains independent of overlay protocols. Selected an online subscriber mechanism over CLI callback scripts, as persistent state requires secure process memory via an event loop and core must request information from subscribers during block composition. Future Neptune coins were selected as the initial example to finalize the interface.

## 4. Updates and Announcements

- No upcoming or past events, announcements, or media uploads were recorded for this period.