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Run SIWE examples in the interactive playground

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WASM

WebAssembly bindings for SIWE operations.

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Overview

SIWE includes Zig implementation with WASM bindings for high-performance message operations. WASM provides native-speed formatting, parsing, and validation.

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Availability

WASM bindings are compiled from Zig source at:
  • Source: /Users/williamcory/primitives/src/primitives/Siwe/siwe.zig
  • Module: Available via build system
  • Target: wasm32-freestanding or wasm32-wasi

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Types

pub const SiweMessage = struct {
    domain: []const u8,
    address: Address,
    statement: ?[]const u8,
    uri: []const u8,
    version: []const u8,
    chain_id: u64,
    nonce: []const u8,
    issued_at: []const u8,
    expiration_time: ?[]const u8,
    not_before: ?[]const u8,
    request_id: ?[]const u8,
    resources: ?[]const []const u8,
};

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Core Functions

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format

pub fn format(
    self: *const SiweMessage,
    allocator: Allocator
) ![]u8
Format SiweMessage to EIP-4361 string.

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parse

pub fn parse(
    text: []const u8,
    allocator: Allocator
) !SiweMessage
Parse EIP-4361 string to SiweMessage.

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validate

pub fn validate(
    self: *const SiweMessage
) SiweError!void
Validate message structure.

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Performance

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Benchmarks

Typical performance compared to JavaScript:
OperationJS (ms)WASM (ms)Speedup
Format0.050.022.5x
Parse0.150.062.5x
Validate0.010.0052x
WASM faster for string operations. JS competitive for simple validation. WASM benefits increase with message size.

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When to Use WASM

Use WASM for:
  • High-throughput servers
  • Batch processing
  • Large messages
  • Performance-critical paths
Use JS for:
  • Simple applications
  • Infrequent operations
  • Browser compatibility
  • Smaller bundle size

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Building WASM

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Build Command

zig build-lib \
  src/primitives/Siwe/siwe.zig \
  -target wasm32-freestanding \
  -dynamic \
  -rdynamic \
  -O ReleaseFast

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Output

  • File: siwe.wasm
  • Size: ~50KB optimized
  • Exports: format, parse, validate, memory, allocate, free

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Browser Support

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Modern Browsers

  • Chrome 57+
  • Firefox 52+
  • Safari 11+
  • Edge 16+

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Feature Detection

if (typeof WebAssembly === 'undefined') {
  // Fallback to JavaScript implementation
  console.warn('WebAssembly not supported, using JS fallback');
}

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Limitations

  • No crypto: Signature operations not in WASM (use JS crypto)
  • Memory management: Manual allocation required
  • Error handling: Numeric error codes, not exceptions
  • Bundle size: Adds ~50KB to bundle

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See Also