Migrate balancer v2 sources to alloy #4023

jmg-duarte · 2026-01-06T11:39:16Z

Description

Migrates Balancer V2 sources module from ethcontract to alloy primitives, continuing the project-wide modernization
effort. This simplifies the codebase and improves type safety across pool fetching, pool implementations, and swap math
calculations.

Changes

Replace ethcontract contract bindings with alloy types in pool fetching
Add alloy block support to recent_block_cache.rs
Migrate all pool types (Weighted, Stable, Composable Stable, LBP) to alloy
Convert swap math modules to use alloy primitives
Update pool storage, registry, and boundary liquidity handlers
Remove ethcontract-specific workarounds from sources/mod.rs

How to test

Existing tests

gemini-code-assist · 2026-01-06T11:40:12Z

Summary of Changes

Hello @jmg-duarte, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request represents a significant internal refactoring effort, transitioning the Balancer V2 liquidity source implementation to leverage the alloy library's modern primitive types and utilities. This modernization streamlines the codebase by adopting a more consistent and up-to-date Ethereum ecosystem library, impacting data structures, contract interactions, and core mathematical operations. The changes also simplify the configuration of Balancer V2 factories, indicating an evolution in how these components are managed within the system.

Highlights

Alloy Migration: This pull request performs an extensive migration of Balancer V2 related code to utilize the alloy library's primitive types and utilities, replacing older ethcontract and web3::types constructs.
Type System Modernization: Key data types such as 256-bit hashes (H256 to B256), unsigned integers (U256), Ethereum addresses (Address), and block identifiers (BlockId) have been updated to their alloy::primitives and alloy::eips equivalents, removing the need for explicit conversion traits like IntoLegacy and IntoAlloy.
Refactored Balancer Factory Handling: The mechanism for configuring and instantiating Balancer V2 factories has been simplified, with the removal of the BalancerFactoryKind enum and associated command-line arguments, suggesting a more streamlined internal management approach.
Updated Arithmetic Operations: Fixed-point arithmetic (Bfp) and other mathematical operations have been adjusted to align with alloy's U256 methods, ensuring compatibility and leveraging alloy's optimized implementations.

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jmg-duarte · 2026-01-06T11:40:48Z

/gemini review

gemini-code-assist

Code Review

This pull request is a significant and well-executed refactoring to migrate Balancer V2 sources from ethcontract types to alloy types. The changes span across multiple crates, including driver, shared, solver, and solvers, consistently replacing types like H256, U256, and BlockId with their alloy equivalents. The removal of BalancerFactoryKind from command-line arguments and its associated logic is a good simplification. The test suite has been diligently updated to reflect these type changes. Overall, the migration appears to be thorough and correct, improving type consistency across the codebase.

gemini-code-assist

Code Review

This pull request migrates the Balancer V2 liquidity sources from ethcontract types to alloy types. This is a significant refactoring that touches many files across driver, shared, solver, and solvers crates. The changes primarily involve replacing ethcontract::{H256, U256} with their alloy counterparts (B256, U256), removing the IntoAlloy/IntoLegacy conversion traits, and updating contract calls and tests to use alloy idioms. Additionally, the configuration of Balancer factories has been refactored, removing the BalancerFactoryKind enum in favor of direct address configuration.

Overall, the migration is well-executed and improves code clarity by using alloy's more idiomatic constants and methods. The changes are consistent across the codebase.

I have one comment regarding a change that seems out of scope for this PR.

I am having trouble creating individual review comments. Click here to see my feedback.

crates/shared/src/sources/mod.rs (79-98)

The removal of PoolAggregator and its PoolFetching implementation seems unrelated to the PR's goal of migrating Balancer V2 sources to Alloy. This logic is for Uniswap V2 pools. Was this removal intentional? If so, it might be better to move it to a separate PR to keep this one focused. If it was not intentional, it should be reverted.

jmg-duarte · 2026-01-07T15:04:43Z

/gemini review

jmg-duarte · 2026-01-07T15:05:53Z

crates/shared/src/sources/balancer_v2/pool_fetching/mod.rs

-#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq, ValueEnum)]
-#[clap(rename_all = "verbatim")]
-pub enum BalancerFactoryKind {
-    Weighted,
-    WeightedV3,
-    WeightedV4,
-    Weighted2Token,
-    StableV2,
-    LiquidityBootstrapping,
-    NoProtocolFeeLiquidityBootstrapping,
-    ComposableStable,
-    ComposableStableV3,
-    ComposableStableV4,
-    ComposableStableV5,
-    ComposableStableV6,


This was unused

jmg-duarte · 2026-01-07T15:06:50Z

crates/shared/src/arguments.rs

Also unused, on the infra repo too

gemini-code-assist

Code Review

This pull request successfully migrates the Balancer V2 sources module from ethcontract to alloy primitives, which is a great step forward in modernizing the codebase. The changes simplify the code and improve type safety across various components like pool fetching, pool implementations, and swap math. The refactoring is well-executed and the code is much cleaner. The identified minor issues, such as a typo in a comment and duplicated test assertions, can be addressed for further improvement.

crates/shared/src/sources/balancer_v2/pool_fetching/pool_storage.rs

m-sz

Small typo, otherwise LGTM!

crates/shared/src/sources/balancer_v2/pool_fetching/pool_storage.rs

…ge.rs Co-authored-by: Marcin Szymczak <[email protected]>

Migrate balancer v2 sources to alloy

9dc5da3

jmg-duarte requested a review from a team as a code owner January 6, 2026 11:39

jmg-duarte marked this pull request as draft January 6, 2026 11:40

gemini-code-assist bot reviewed Jan 6, 2026

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jmg-duarte added 3 commits January 6, 2026 11:59

Address CI failures

a869b5f

Merge branch 'main' into jmgd/alloy/sources

c886f97

fmt and comp fix

3c8f31c

jmg-duarte commented Jan 7, 2026

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crates/shared/src/arguments.rs

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jmg-duarte Jan 7, 2026

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Also unused, on the infra repo too

jmg-duarte changed the title ~~[NEEDS #4002] Migrate balancer v2 sources to alloy~~ Migrate balancer v2 sources to alloy Jan 7, 2026

jmg-duarte marked this pull request as ready for review January 7, 2026 15:07

gemini-code-assist bot reviewed Jan 7, 2026

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crates/shared/src/sources/balancer_v2/pool_fetching/pool_storage.rs Outdated Show resolved Hide resolved

m-sz approved these changes Jan 7, 2026

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crates/shared/src/sources/balancer_v2/pool_fetching/pool_storage.rs Outdated Show resolved Hide resolved

Update crates/shared/src/sources/balancer_v2/pool_fetching/pool_stora…

5640967

…ge.rs Co-authored-by: Marcin Szymczak <[email protected]>

squadgazzz approved these changes Jan 7, 2026

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jmg-duarte added this pull request to the merge queue Jan 7, 2026

Merged via the queue into main with commit b9ff845 Jan 7, 2026
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jmg-duarte deleted the jmgd/alloy/sources branch January 7, 2026 16:29

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jmg-duarte commented Jan 6, 2026 •

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Description

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Summary of Changes

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crates/shared/src/sources/mod.rs (79-98)

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jmg-duarte commented Jan 6, 2026 •

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