eth.zig

The Ethereum library for Zig.

eth.zig provides everything you need to interact with Ethereum from Zig -- signing transactions, encoding ABI calls, managing HD wallets, reading ERC-20 tokens, talking to nodes over JSON-RPC, and more.

Why eth.zig?

Zero dependencies -- Built entirely on Zig's standard library. No C bindings, no vendored C code, no system libraries. Just zig build and go.

Comptime-first -- Function selectors and event topics are computed at compile time with zero runtime cost. The compiler does the hashing so your program doesn't have to.

Pure Zig crypto -- secp256k1 ECDSA, Keccak-256, BIP-32/39/44 HD wallets -- all implemented in pure Zig. No OpenSSL, no libsecp256k1, no FFI.

Quick Start

Derive an address from a private key

const eth = @import("eth");

const private_key = try eth.hex.hexToBytesFixed(32, "ac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80");
const signer = eth.signer.Signer.init(private_key);
const addr = try signer.address();
const checksum = eth.primitives.addressToChecksum(&addr);
// "0xf39Fd6e51aad88F6F4ce6aB8827279cffFb92266"

Sign and send a transaction

const eth = @import("eth");

var transport = eth.http_transport.HttpTransport.init(allocator, "https://rpc.example.com");
defer transport.deinit();
var provider = eth.provider.Provider.init(allocator, &transport);

var wallet = eth.wallet.Wallet.init(allocator, private_key, &provider);
const tx_hash = try wallet.sendTransaction(.{
    .to = recipient_address,
    .value = eth.units.parseEther(1.0),
});

Read an ERC-20 token

const eth = @import("eth");

// Comptime selectors -- zero runtime cost
const balance_sel = eth.erc20.selectors.balanceOf;

// Or use the typed wrapper
var token = eth.erc20.ERC20.init(allocator, token_addr, &provider);
const balance = try token.balanceOf(holder_addr);
const name = try token.name();
defer allocator.free(name);

Comptime function selectors and event topics

const eth = @import("eth");

// Computed at compile time -- zero runtime cost
const transfer_sel = eth.abi_comptime.comptimeSelector("transfer(address,uint256)");
// transfer_sel == [4]u8{ 0xa9, 0x05, 0x9c, 0xbb }

const transfer_topic = eth.abi_comptime.comptimeTopic("Transfer(address,address,uint256)");
// transfer_topic == keccak256("Transfer(address,address,uint256)")

HD wallet from mnemonic

const eth = @import("eth");

const words = [_][]const u8{
    "abandon", "abandon", "abandon", "abandon",
    "abandon", "abandon", "abandon", "abandon",
    "abandon", "abandon", "abandon", "about",
};
const seed = try eth.mnemonic.toSeed(&words, "");
const key = try eth.hd_wallet.deriveEthAccount(seed, 0);
const addr = key.toAddress();

Installation

One-liner:

zig fetch --save git+https://github.com/StrobeLabs/eth.zig.git#v0.1.0

Or add manually to your build.zig.zon:

.dependencies = .{
    .eth = .{
        .url = "git+https://github.com/StrobeLabs/eth.zig.git#v0.1.0",
        .hash = "...", // run `zig build` and it will tell you the expected hash
    },
},

Then import in your build.zig:

const eth_dep = b.dependency("eth", .{
    .target = target,
    .optimize = optimize,
});
exe.root_module.addImport("eth", eth_dep.module("eth"));

Examples

The examples/ directory contains self-contained programs demonstrating each major feature:

Example	Description	Requires RPC
01_derive_address	Derive address from private key	No
02_check_balance	Query ETH balance via JSON-RPC	Yes
03_sign_message	EIP-191 personal message signing	No
04_send_transaction	Send ETH with Wallet	Yes (Anvil)
05_read_erc20	ERC-20 module API showcase	Yes
06_hd_wallet	BIP-44 HD wallet derivation	No
07_comptime_selectors	Comptime function selectors	No

Run any example:

cd examples && zig build && ./zig-out/bin/01_derive_address

Modules

Layer	Modules	Description
Primitives	primitives, uint256, hex	Address, Hash, Bytes32, u256, hex encoding
Encoding	rlp, abi_encode, abi_decode, abi_types, abi_comptime	RLP and ABI encoding/decoding, comptime selectors
Crypto	secp256k1, signer, signature, keccak, eip155	ECDSA signing (RFC 6979), Keccak-256, EIP-155
Types	transaction, receipt, block, blob, access_list	Legacy, EIP-2930, EIP-1559, EIP-4844 transactions
Accounts	mnemonic, hd_wallet	BIP-32/39/44 HD wallets and mnemonic generation
Transport	http_transport, ws_transport, json_rpc, provider, subscription	HTTP and WebSocket JSON-RPC transports
ENS	ens_namehash, ens_resolver, ens_reverse	ENS name resolution and reverse lookup
Client	wallet, contract, multicall, event, erc20, erc721	Signing wallet, contract interaction, Multicall3, token wrappers
Standards	eip712, abi_json	EIP-712 typed data signing, Solidity JSON ABI parsing
Chains	chains	Ethereum, Arbitrum, Optimism, Base, Polygon definitions

Features

Feature	Status
Primitives (Address, Hash, u256)	Complete
RLP encoding/decoding	Complete
ABI encoding/decoding (all Solidity types)	Complete
Keccak-256 hashing	Complete
secp256k1 ECDSA signing (RFC 6979, EIP-2 low-S)	Complete
Transaction types (Legacy, EIP-2930, EIP-1559, EIP-4844)	Complete
EIP-155 replay protection	Complete
EIP-191 personal message signing	Complete
EIP-712 typed structured data signing	Complete
EIP-55 address checksums	Complete
BIP-32/39/44 HD wallets	Complete
HTTP transport	Complete
WebSocket transport (with TLS)	Complete
JSON-RPC provider (24+ methods)	Complete
ENS resolution (forward + reverse)	Complete
Contract read/write helpers	Complete
Multicall3 batch calls	Complete
Event log decoding and filtering	Complete
Chain definitions (5 networks)	Complete
Unit conversions (Wei/Gwei/Ether)	Complete
ERC-20 typed wrapper	Complete
ERC-721 typed wrapper	Complete
JSON ABI parsing	Complete
EIP-7702 transactions	Planned
IPC transport	Planned
Provider middleware (retry, caching)	Planned
Hardware wallet signers	Planned

Feature Comparison vs Zabi

Feature	eth.zig	Zabi
Dependencies	0	0
Comptime selectors	Yes	No
Pure Zig crypto (secp256k1)	Yes	No (C binding)
ABI encode/decode	Yes	Yes
HD wallets (BIP-32/39/44)	Yes	Yes
ERC-20/721 wrappers	Yes	No
JSON ABI parsing	Yes	Yes
WebSocket transport	Yes	Yes
ENS resolution	Yes	Yes
EIP-712 typed data	Yes	Yes
Multicall3	Yes	No

Requirements

• Zig >= 0.15.2

Running Tests

zig build test                # Unit tests
zig build integration-test    # Integration tests (requires Anvil)

Contributing

Contributions are welcome. Please open an issue or pull request on GitHub.

Before submitting:

1. Run zig build test and ensure all tests pass.
2. Follow the existing code style -- no external dependencies, comptime where possible.
3. Add tests for any new functionality.

License

MIT -- see LICENSE for details.

Copyright 2025-2026 Strobe Labs