Ashen SDK

The Ashen SDK provides Zig modules for writing smart contracts that run on Ashen’s RISC-V execution environment.

Quick Start

const sdk = @import("ashen-sdk");

export fn _start(calldata_ptr: [*]const u8, calldata_len: usize) sdk.ByteSlice {
    sdk.heap.reset();
    const calldata = if (calldata_len == 0) &[_]u8{} else calldata_ptr[0..calldata_len];
    // Your contract logic here
    return sdk.ByteSlice.from(result);
}

pub const panic = sdk.panic;

Modules

sdk.storage - Persistent key-value storage

const storage = sdk.storage;

// Read/write raw bytes
const value = storage.read(key);
storage.write(key, data);

// Typed helpers for u128
const balance = storage.readU128(key);
storage.writeU128(key, amount);

sdk.context - Block and transaction context

const ctx = sdk.context;

const sender = ctx.caller();      // Immediate caller
const tx_origin = ctx.origin();   // Transaction originator
const height = ctx.blockHeight();
const attached = ctx.value();     // Attached value

sdk.crypto - Hash functions

const crypto = sdk.crypto;

const k_hash = crypto.keccak256(data);
const s_hash = crypto.sha256(data);
const b_hash = crypto.blake3(data);

sdk.events - Typed event emission

const events = sdk.events;

// Define event signature
const Transfer = events.define("Transfer(address,address,uint256)");

// Emit with indexed topics
Transfer.emit2(from, to, events.toTopicU128(amount), &[_]u8{});

sdk.math - Fixed-point arithmetic

const math = sdk.math;

const shares = math.isqrt(product);      // Integer sqrt
const fee = math.bpsMul(amount, 30);     // 0.3% (30 bps)
const smaller = math.min(u128, a, b);
const larger = math.max(u128, a, b);

sdk.guards - Safety utilities

const guards = sdk.guards;

// Reentrancy protection
try guards.enterNonReentrant();
defer guards.exitNonReentrant();

// Safe arithmetic (returns error on overflow)
const sum = guards.safeAdd(u128, a, b) catch return error;
const diff = guards.safeSub(u128, a, b) catch return error;

Module Reference

Module	Import	Purpose
`heap`	`sdk.heap`	Bump allocator
`storage`	`sdk.storage`	State read/write
`context`	`sdk.context`	Caller, origin, block info
`crypto`	`sdk.crypto`	Keccak256, SHA256, Blake3
`events`	`sdk.events`	Event emission
`guards`	`sdk.guards`	Reentrancy, safe math
`math`	`sdk.math`	WAD/RAY/BPS math

Next Steps

Zig Guide Detailed Zig contract tutorial

IDL & ABI Interface definitions

Examples Sample contracts

Deploying Deployment guide

Execution VM architecture

Gas & Fees Gas metering

RPC API Contract calls