evm-tracer

A high-performance EVM execution tracer with prestate reconstruction, custom tracer support, and parallelized replay.

In the Ethereum ecosystem, extracting a complete list of ERC-20 token holders might sound straightforward — yet in practice, it’s one of the hardest challenges in reconstructing on-chain state.

• The EVM’s mapping(address => uint256) is non-iterable by design.
• Transfer events can be missing, reordered, or inconsistent.
• Archive nodes are expensive and resource-intensive.
• JSON-RPC queries are slow and limited by rate controls.

evm-tracer addresses this by replaying EVM execution directly, capturing every balance mutation as it happens —
ensuring complete, verifiable, and event-independent state reconstruction.

Instead of inferring state from events, evm-tracer directly observes how the EVM state evolves in real time — offering true God-mode visibility into on-chain behavior.

🚀 Features

• Full Block Replay — execute every transaction locally and reconstruct state transitions precisely.
• Prestate Support — load pre-execution state using debug_traceBlockByNumber.
• Custom Tracer Support — use built-in or custom Go tracers (callTracer, 4byteTracer, prestateTracer, etc).
• Parallel Execution — multi-core accelerated transaction replay.
• Structured JSON Output — returns detailed call traces and receipts.
• Archive-Level Accuracy — no reliance on event logs or approximations.

🧠 Core Concept

evm-tracer doesn’t guess the state — it observes it.

• Captures SSTORE operations that modify contract storage.
• Replays full blocks locally for verifiable execution context.
• Outputs both execution traces and state changes as structured JSON.

This is not log parsing — it’s state machine replay.

🧮 Use Cases

• Reconstruct ERC-20/721/1155 token holder snapshots
• Analyze MEV and internal transactions
• Trace contract execution paths and storage slot mutations
• Lightweight archive-node alternative
• On-chain audit and compliance reporting

⚡ Performance Comparison

Feature	Traditional Approach	evm-tracer
Data Source	Transfer Events + eth_call	Full Block + Prestate
RPC Calls	Tens of thousands	Only 2
Accuracy	Depends on event integrity	State-level accuracy
Historical Query	Requires Archive Node	Native support
Bottleneck	Network / RPC rate	Local computation

🧪 Example Usage

Example: trace all transactions in block #20000000 on Ethereum mainnet.

make run

🔍 WASM Demo

build to WASM:

make wasm

UI and demo: https://1block.dev

🧭 Roadmap

• Multi-chain support (BSC, Polygon, Arbitrum, Optimism, etc)
• Built-in parsers for ERC-20 / ERC-721 / ERC-1155 state changes
• Wasm tracer engine
• gRPC / REST API / CLI service layer
• Web-based visualization tool

📄 License

MIT