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hrkrshnn /
Last active November 2, 2023 13:09
Some generic writeup about common gas optimizations, etc.

Upgrade to at least 0.8.4

Using newer compiler versions and the optimizer gives gas optimizations and additional safety checks for free!

The advantages of versions 0.8.* over <0.8.0 are:

  • Safemath by default from 0.8.0 (can be more gas efficient than some library based safemath).
  • Low level inliner from 0.8.2, leads to cheaper runtime gas. Especially relevant when the contract has small functions. For
karmacoma-eth /
Last active August 27, 2023 18:42
Sending Ether Cheat Sheet

Sending Ether Cheat Sheet


🥇 Instead of sending Ether, use the withdrawal pattern

🥈 If you really need to send Ether, use a safe wrapper like OpenZeppelin's Address.sendValue(addr, amount)

🥉 If you really need to send Ether without dependencies, use (bool success, ) ={value: amount}("")

karmacoma-eth / quine.etk
Last active March 18, 2023 18:28
EVM quine
View quine.etk
# quine.etk
# ⬜ => ⬜
# A quine is a computer program which takes no input and produces a copy of its own source code as its only output.
# 0x80...f3 is the compiled code excluding the push16 instruction (from dup1 to return)
push16 0x8060801b17606f5953600152602136f3
# --- stack ---
dup1 # code code
push1 128 # 128 code code
karmacoma-eth / rev-calldata-chunks.huff
Created February 23, 2023 18:35
reverse calldata in chunks of 32 bytes
View rev-calldata-chunks.huff
// Reverse bytes received in calldata (abcd -> dcba)
// code length 206
/// @author Philippe Dumonet <> --
/// @author karma (@0xkarmacoma) --
/// @author kaden.eth (@0xKaden) --
#define macro reverse_word() = takes(1) returns(1) {
// [x0]