Argument-0007: Retention at Rank I

Member details

• Matrix username: @michal:parity.io
• Polkadot address: 14T9NGF7LdCY7SK2j6oNXmB9NqfKYyrxBChUvYRjtFdvZBMo
• Current rank: 1
• Date of initial induction: 2024/06/02
• Date of last report: 2026/03/05
• Area(s) of Expertise/Interest: Substrate node ,Transaction Pool, ChainSpec/GenesisConfig

Reporting period

• Start date: 2026/03/05
• End date: 2026/06/08

Argument

During this period I worked on the Substrate node, the fork-aware transaction pool, light-client data retrieval, test tooling, and JAM metrics observability.

Light-client data retrieval (bitswap). I worked on a streaming bitswap RPC: I extended the existing bitswap implementation with streaming functionality. The method is specified in json-rpc-interface-spec#186, implemented node-side in polkadot-sdk#12029, with matching light-client support in smoldot (#3264, plus an advertised-address fix in #3245). To get some visibility into this load I proposed a light-client/bitswap metrics scheme (polkadot-sdk#12083) and added the litep2p bitswap metrics in #12232. I also reviewed the related PRs: the bitswap client (#12038), TransactionStorageApi v2 (#11939), prefetched indexed transactions (#12086), and the runtime-api storage-overlay change (#12084), which deepened my knowledge of the bulletin chain.

Fork-aware transaction pool. The pool continues in maintenance mode, mostly around stuck-transaction edge cases. I looked into and fixed a case where a per-fork validation ban propagates across all views and silently rejects an otherwise-valid transaction for the full ban duration (unban viewless transactions after mempool revalidation, #11731), and fixed a wrong inblock event (#11733).

Test tooling — Zombienet snapshots. Building DB snapshots for warp-sync and light-client smoke tests had been hand-rolled in each test. I proposed (zombienet-sdk#541) and added a snapshot API to the SDK.

JAM / PolkaJam. I continued the metrics observability work on jamtart: after some further events-streaming improvements, I worked on #15 (a cross-event enricher, Grafana endpoints for JIP-3 telemetry, on-chain endpoints from JAM RPC, some database schema and query changes, and Grafana dashboards). This is still very much work in progress that I plan to get back to.

The PoV size reclaim fix (#10215) and RFC-158 remain open and carried over from the previous period.

Voting record

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