Argument-0010: Retention at Rank II

Member details

• Current rank: II
• Polkadot address: 13WGadgNgqSjiGQvfhimw9pX26mvGdYQ6XgrjPANSEDRoGMt
• Date of initial induction: 2024/04/22
• Date of last report: 2026/04/15
• Link to last report: https://github.com/polkadot-fellows/Evaluations/pull/278
• Area(s) of Expertise/Interest: WebAssembly, PolkaVM, PVF execution, host functions, statement store, proof of personhood

Reporting period

• Start date: 2026/04/16
• End date: 2026/07/05

Argument

During the reporting period, I stayed a core part of the team, carrying forward my established lines of work around PVF execution and host functions, and taking on a new major area — the statement store that underpins the Proof of Personhood effort.

RFC-145 (runtime-side memory allocator and host functions). I kept driving the reference implementation forward. The main PR (#8641) is under active review, and I peeled off self-contained improvements to make it landable in pieces — most notably public-keys caching (#12099, merged), with a refactor of the storage cursor allocation (#12200) and passing the storage root hash unencoded (#12117) in flight. This is the long-awaited change that makes PVF execution more deterministic and faster, and it is now close to the finish line.

BLS12-381 host functions (RFC-156). I continued stabilizing the BLS signatures and their host functions (#10327), which are needed to equip BEEFY with BLS and are essential for the accountable light-client protocol. Along the way I tracked down and fixed two nasty defects on the author_rotateKeys / BEEFY paired-session-key path in the filesystem-backed keystore (#12053): a deterministic panic when generating ecdsa_bls381 keys without a seed, and a keystore filename overflow for BLS381 / ECDSA_BLS381 keys that exceeded the 255-byte limit.

Statement store — Proof of Personhood infrastructure. I took over the index-scaling work for the statement store, which is the backbone of the Proof of Personhood effort. Following the roadmap in #10910, I landed stage 1 (#11480, merged), splitting the single index into independent read/write structures to cut lock contention, and I am now pushing stage 2a (#12304), which moves the read and "evicted" indexes to disk behind a cache and removes the RAM bound on how many statements a node can hold.

Correctness and toolchain. I root-caused and fixed a subtle state-trie bug where the OverlayedChanges::storage_root cache bled across StateVersion (#11833 → #11918, merged), and adapted the SDK to a rust-lld 1.96.0 regression that broke Wasm imports and could have blocked the toolchain upgrade (#12440, merged).

PolkaVM and virtualization. I kept the PolkaVM-for-parachain-runtimes MVP rebased and alive pending RFC-145 adoption, and reviewed the sp-virtualization API rework (#11767) that builds on the virtualization work I landed in the previous period.

To summarize, my work during the reporting period was valuable, and therefore, I'm applying for retention at Rank II.

Voting record