Backrun bundles

[dvush]

📝 Summary

Adds support for backrun bundles.

• adds eth_sendBackrunBundle rpc (see new rpc.rs)
• adds backrun bundle pool to store backrun bundles (see new '*pool.rs`)
• modified block builder to include backrun bundles (see context.rs change)

See module level docs in backrun_bundle/mod.rs for detailed explanation.

Also see docs and definitions for the following structs: BackrunBundleGlobalPool, BackrunBundlePayloadPool, StoredBackrunBundle, BackrunBundleRPCArgs.

💡 Motivation and Context

Backrun bundle is a new type of bundle that allows backrunning mempool transactions. If enabled, after mempool transaction is included builder tries to include the best available backruns for that transactions.

---

✅ I have completed the following steps:

• Run make lint
• Run make test
• Added tests (if applicable)

[Copilot]

Pull request overview

This pull request adds comprehensive support for backrun bundles to the op-rbuilder. A backrun bundle pairs a target transaction (already in the mempool) with a backrun transaction that executes immediately after the target lands in a block. The feature is opt-in via the --backruns.enabled flag.

Changes:

• Adds eth_sendBackrunBundle RPC endpoint with validation for bundle structure, block ranges, and replacement logic
• Implements a two-tier pool system: global pool for managing bundles across blocks and per-block payload pools for builder access
• Integrates backrun processing into the block builder to execute backruns after successful target transactions with priority fee and execution validation
• Adds comprehensive CLI configuration options, metrics tracking, and automatic pool cleanup on chain progression

Reviewed changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
crates/op-rbuilder/src/backrun_bundle/mod.rs	Module documentation and public API definitions for backrun bundle feature
crates/op-rbuilder/src/backrun_bundle/rpc.rs	RPC endpoint implementation with validation and bundle submission handling
crates/op-rbuilder/src/backrun_bundle/global_pool.rs	Global pool managing bundles across blocks with replacement logic
crates/op-rbuilder/src/backrun_bundle/payload_pool.rs	Per-block pool with priority-based backrun selection and filtering
crates/op-rbuilder/src/backrun_bundle/maintain.rs	Background task for pool cleanup on canonical state changes
crates/op-rbuilder/src/backrun_bundle/args.rs	CLI arguments and limit checking logic
crates/op-rbuilder/src/backrun_bundle/metrics.rs	Metrics definitions for pool monitoring
crates/op-rbuilder/src/backrun_bundle/test_utils.rs	Test utilities for creating backrun bundles
crates/op-rbuilder/src/builders/context.rs	Integration of backrun processing into block building pipeline
crates/op-rbuilder/src/builders/mod.rs	Added backrun pool and args to builder configuration
crates/op-rbuilder/src/builders/standard/payload.rs	Backrun context initialization for standard builder
crates/op-rbuilder/src/builders/flashblocks/payload.rs	Backrun context initialization for flashblocks builder
crates/op-rbuilder/src/builders/flashblocks/ctx.rs	Backrun context for flashblocks syncer
crates/op-rbuilder/src/launcher.rs	RPC registration and maintenance task spawning
crates/op-rbuilder/src/tests/framework/instance.rs	Test framework integration for backrun RPC
crates/op-rbuilder/src/tests/framework/txs.rs	Test helpers for sending backrun bundles
crates/op-rbuilder/src/tests/backrun.rs	Comprehensive test suite covering all backrun scenarios
crates/op-rbuilder/src/tests/mod.rs	Test module registration
crates/op-rbuilder/src/primitives/reth/execution.rs	New execution result variants for backrun-specific failures
crates/op-rbuilder/src/metrics.rs	Added backrun-related metrics to builder metrics
crates/op-rbuilder/src/args/op.rs	Added backrun bundle args to main CLI args
crates/op-rbuilder/src/lib.rs	Module registration

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

Pull request overview

Copilot reviewed 22 out of 22 changed files in this pull request and generated 3 comments.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.