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Matthew
Matthew

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evm-lens: Instant, Local EVM CLI Bytecode Disassembly

#evm #rust #cli #tooling

“Understanding what the EVM is actually doing is the first step toward optimizing your gas usage.”

I’m thrilled to announce evm-lens v0.1.1, a lean, lightning-fast CLI and library that transforms raw EVM bytecode into a readable, color-coded opcode listing—all on your machine, in milliseconds.

Demo

🚀 TL;DR

  • v0.1.1 adds:
    • STDIN loader (--stdin) – pipe in hex from any source
    • On-chain loader (--address) – fetch code via eth_getCode
  • Works with .bin files, raw hex, or live contracts
  • Pure Rust, zero external dependencies beyond revm
  • ✅ Fully tested, CI-friendly, no SaaS lock-in 
cargo install evm-lens
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🔍 The Pain Point

Smart-contract auditors, MEV researchers, and tooling engineers spend too much time:

  1. Copy-pasting hex into online disassemblers (often rate-limited or incomplete)
  2. Writing brittle scripts (curl | jq | sed) to fetch on-chain code
  3. Context-switching between terminal, browser, and local files

By the time you’ve wrangled inputs, the actual opcode analysis feels like an afterthought.

🔧 How evm-lens Helps

1. Instant, Local Disassembly 

evm-lens --file MyToken.bin | less -R
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In under 10 ms, you get a line-numbered, color-coded opcode dump—no network round-trips, no web UI.

2. Flexible Input Sources

  • Direct Hex 
  evm-lens 60FF61ABCD00
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  • File 
  evm-lens --file path/to/Token.bin
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  • Standard Input 
  echo "0x60FF61ABCD00" | evm-lens --stdin
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  • Blockchain Input 
  evm-lens --address 0xAbC… --rpc https://eth.llamarpc.com
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👥 Who Should Care

  • Security Auditors & Researchers Integrate evm-lens into your CI pipeline for reliable, local bytecode snapshots.
  • Gas Optimizers Track opcode counts and static gas to measure PR impact instantly.
  • Tooling Authors Import evm-lens-core into your Rust projects and build on a battle-tested foundation.

🔮 What’s Next

Release Highlight
v0.2 --abi flag: resolve 4byte selectors & annotate CALL opcodes
v0.3 storage-diff subcommand: slot layouts, collision grading, HTML
v0.4 gas-flame: offline SVG/CSV flamegraphs for gas hot-spot analysis
v0.5 tracing: trace live blockchain transactions locally - similar to Tenderly

📥 Get Started

  1. Install or upgrade 
   cargo install evm-lens
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  1. Run the CLI 
   # Direct hex input
   evm-lens 60FF61ABCD00

   # From file
   evm-lens --file path/to/Token.bin

   # From stdin
   echo "0x60FF61ABCD00" | evm-lens --stdin

   # On-chain
   evm-lens --address 0xAbC… --rpc https://eth.llamarpc.com
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  1. Explore the library 
   use lens_core::disassemble;
   let bytecode = hex::decode("60FF61ABCD00")?;
   let ops = disassemble(&bytecode)?;
   for (position, opcode) in ops {
       println!("{:04x}: {:?}", position, opcode);
   }
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Find the repo, file issues, and leave a star:

👉 https://github.com/andyrobert3/evm-lens

Thanks for reading! Your feedback drives this project—drop issues, PRs, or comments in Discussions. Let’s make EVM bytecode transparent and accessible to everyone.

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