@xlabs-xyz/ts-sdk

A collection of TypeScript utilities for building robust, type-safe blockchain applications. The monorepo provides foundational tools from low-level binary serialization to high-level Solana fork testing.

Packages

Package	Description
@xlabs-xyz/const-utils	Type-safe utilities for readonly/const data structures, branding, and type manipulation
@xlabs-xyz/utils	Common runtime utilities: encoding, hashing, bigint JSON, assertions
@xlabs-xyz/binary-layout	Declarative DSL for binary serialization/deserialization with strong typing
@xlabs-xyz/amount	Type-safe amounts with units and arbitrary-precision arithmetic
@xlabs-xyz/common	Glue layer tying lower-level packages into practical building blocks
@xlabs-xyz/evm	Ethereum/EVM utilities: ERC20 client, Multicall3 queries, EIP-2612 permits, binary layouts
@xlabs-xyz/svm	Solana/SVM utilities and helpers
@xlabs-xyz/fork-svm	Anvil-style local SVM fork with lazy account fetching for testing

Dependency Graph

const-utils ──┬── utils ──────────┐
              ├── amount ─────────┼── common ──┬── svm ── fork-svm
              └── binary-layout ──┘            └── evm

Package Summaries

const-utils

The foundation layer providing type-safe utilities for working with readonly and const data structures:

• Const Maps: Bidirectional, type-safe mappings from hierarchical const specifications
• Array/Object Utilities: Const-preserving transformations (mapTo, zip, pick, omit, etc.)
• Branding: Hierarchical type branding with tag accumulation for nominal typing
• Type Utilities: RoUint8Array, deep readonly/mutable helpers, tuple types
• Piping: Function composition (pipe), assertions (ensure, forbid), predicates

utils

Common runtime utilities with minimal dependencies:

• Encoding: hex, base58, base64, bech32, bignum, UTF-8 bytes
• Hashing: Re-exports from @noble/hashes and @noble/curves
• BigInt JSON: Serialization that preserves bigints
• Assertions: Simple runtime checks (assertEqual, assertDistinct)

binary-layout

A declarative DSL for binary data serialization/deserialization:

• Pure TypeScript: No code generation or meta-compilation required
• Strong Typing: DeriveType infers types from layout definitions
• Composable: Nested structures, arrays, switches (tagged unions)
• Automatic Discrimination: Generates efficient discriminators for layout sets
• Custom Conversions: Transform between binary and domain types

amount

Type-safe handling of amounts with units and arbitrary-precision arithmetic:

• Rational: Exact arithmetic via normalized fractions
• Kind: Define dimensions with multiple unit systems (ETH/Gwei/wei, USD/cents, etc.)
• Amount: Values paired with kinds, with unit conversion and formatting
• Conversion: Type-safe ratios between kinds (prices, exchange rates)

common

Glue layer that ties the lower-level packages together:

• Layout Items: Binary-layout items that serialize to/from Amount, timestamps, etc.
• Units: Predefined kinds for currencies (USD, BTC, ETH, SOL), percentages, duration, bytes
• Helpers: Unit definition utilities for creating custom kinds

evm

Ethereum/EVM utilities built on viem:

• Layout Primitives: Word-aligned binary layouts, function selectors, storage slot computation
• Batched Queries: Multicall3-based read batching with block-consistent results
• ERC20 Client: Compose approve, transfer, permit, and query call data
• EIP-712 / EIP-2612: Domain reconstruction and permit message composition

svm

Solana/SVM utilities built on @solana/kit:

• Client Utilities: Type-safe RPC wrappers with optional Amount integration
• PDA Derivation: findPda, findAta, with type-safe seed handling
• Binary Layouts: Items for addresses, lamports, SPL accounts (mint, token, ALT)
• Instruction Composition: Type-safe instruction and transaction building
• Constants: All standard program IDs, sysvar IDs, size constants

fork-svm

Anvil-style local SVM fork for Solana testing:

• Lazy Forking: Accounts fetched on-demand from mainnet/devnet
• State Manipulation: Modify accounts, clock, and balances
• Snapshots: Save/restore state; persist to disk for reproducible CI
• Drop-in RPC: Compatible interface for existing RPC-based code
• In-Process: Fast, no separate validator process

Installation

# Install individual packages as needed
pnpm add @xlabs-xyz/const-utils
pnpm add @xlabs-xyz/binary-layout
pnpm add @xlabs-xyz/amount
# etc.

Packages use peer dependencies for internal cross-references, so install the packages you need directly.