This Month in Forest — August 🌲

[AlexeyKrasnoperov]

This Month in Forest — August 🌲

Welcome to the August edition of This Month in Forest! We are excited to share the latest updates and improvements to the Forest Filecoin client (and more!).

Highlights

• v0.29.0 "Fëanor" released. Optional, yet improving snapshot UX, adding FRC-0108, and fixing ChainNotify RPC Method.
• 3 FIPs important for NV27 were implemented and merged into builtin-actors: FIP-0101, FIP-0103, FIP-0106. Great work, @akaladarshi, @sudo-shashank and @elmattic!
• Forest team introduced a cacheless iterator in the fvm_ipld_amt crate. This allows for a much more performant iterations of the AMT. An example use-case is iterating the mainnet deals AMT; a regular caching iteration takes over 50 minutes and over 64 GiB of memory. The Amt::for_each_cacheless enables performing this iteration in under two minutes with minimal RAM overhead, which in turn allows for more efficient APIs. #2189 @LesnyRumcajs 💪
• Want to understand how we tackled memory challenges in Forest? Hubert (@LesnyRumcajs) wrote an excellent article on Rust memory analysis: Memory analysis in Rust.
• All archival calibnet snapshots were backfilled till 2025-08-09. 🏗️ We're working on backfilling mainnet snapshots.
• NV27 Network Upgrade Planning Discussion

Request for comments

In Forest, we're always looking for ways to make Filecoin more efficient. We’ve implemented an experimental API that optimizes the usage of Filecoin.StateMarketDeals. Specifically, we introduced the Forest.StateMarketDealsDump and Forest.StateMarketDealsFiltered methods. With these methods, some of our clients are seeing significant performance improvements (up to 10x fewer resources used and 10x faster execution). Since these methods are still experimental, we’re not certain they will remain unless there is validated client demand. If you think they could be useful for your app, feel free to leave your comments in the PR: #5907

Development

F3 Snapshots are ready 🚀

F3 Snapshots, introduced by FIP-0108, are now fully supported in Forest. Import, export, the necessary tooling are in place - thanks to @hanabi1224 🏆 (#5886, #5956, #5963).

StateDecodeParams

This beast was never the easiest to deal with, but we’ve taken a few more steps to tame it.
Filecoin.StateDecodeParams got 8 feature PRs in August, which brought support for reward, multisig, verifiedreg, miner, evm, eam, ethaccount and payment channel actors.

Conformance Tests

At Forest, we take the reliability and interoperability of nodes seriously. That's why we cover RPC methods with conformance tests to ensure that Forest and Lotus respond to API calls in the same correct way. This month, we improved our testing framework and expanded coverage to include more methods critical for wallet operations: Filecoin.WalletBalance, Filecoin.WalletValidateAddress, and Filecoin.WalletVerify (#5959).

Other

As always, see the CHANGELOG for details. Note that it contains primarily client-facing changes, so if you're interested in the nitty-gritty details, you'll need to go through the commit history. 🤓