# Fystack

> Fystack is a self-custody digital asset platform. Its API lets you create and manage MPC and HD wallets, receive deposits, send withdrawals, sign Web3 transactions, enforce programmable policies and multi-party approvals, and receive webhooks, across EVM chains, Solana, Tron, Bitcoin and more.

Notes for AI agents:

- Production API base URL: `https://api.fystack.io/api/v1`. Sandbox: `https://api.enterprise-sandbox.fystack.io/api/v1`. The SDK defaults to production when no environment is set.
- Every request is signed. Read [API Authentication](https://docs.fystack.io/authentication.md) before writing request code.
- Official SDKs: TypeScript `@fystack/sdk` (npm) and Go `github.com/fystack/platform-sdk-go`. Prefer them over hand-rolled signing.
- Any page on this site is available as Markdown by appending `.md` to its URL, or by sending `Accept: text/markdown`.

## Product Documentation

- [Product Documentation](https://docs.fystack.io/product.md): Overview of the Fystack product: workspaces, network and user management, approval groups, security, withdrawals, Web3 signing, gas station, automation, policies, and alerts.
- [Withdrawal](https://docs.fystack.io/product/withdrawal.md): Send funds from a Fystack wallet to an external address.
- [Web3 Sign](https://docs.fystack.io/product/web3-sign.md): Create Web3 signing requests through the SDK or API and review pending approvals in the dashboard.
- [Approval Group](https://docs.fystack.io/product/approval-group.md): An approval group is a named set of workspace members plus the number of signatures required from them before a sensitive action takes effect.
- [Address Book](https://docs.fystack.io/product/address-book.md): A multi-chain address book entry is a named record holding every address a single counterparty uses across the chains it supports.
- [Automation & Sweep](https://docs.fystack.io/product/automation.md): Fystack's automation tools help businesses streamline their crypto operations, reduce development time, and minimize operational overhead.
- [Gas Station](https://docs.fystack.io/product/gas-station.md): The Gas Station is Fystack's built-in gas management hub.
- [Alerts](https://docs.fystack.io/product/alerts.md): The Alerts module lets you monitor wallet activity in real time and receive instant notifications through external channels like Telegram.
- [Policies](https://docs.fystack.io/product/policies.md): Set programmable guardrails that automatically allow, block, or route sensitive actions through normal approval in your workspace.
- [Security & 2FA](https://docs.fystack.io/product/security.md): Secure your Fystack account with Passkey and TOTP two-factor authentication.
- [Workspace](https://docs.fystack.io/product/workspace.md): A Workspace is the top-level organizational unit in Fystack. It acts as an isolated environment where you manage wallets, users, transactions, and settings independently from other workspaces.
- [User Management](https://docs.fystack.io/product/user-management.md): Manage workspace members, control access levels, and maintain operational security through Fystack's User Management module.
- [Asset Management](https://docs.fystack.io/product/asset-management.md): The Asset page lists every cryptocurrency asset configured for your workspace, along with its contract address, decimal precision, and current status.
- [Network Management](https://docs.fystack.io/product/network.md): Manage and monitor your blockchain networks efficiently. Configure network settings, monitor health status, and maintain data integrity through our network management tools.

## Guides

- [Introduction](https://docs.fystack.io/index.md): Fystack helps Web3 projects, fintechs & stablecoin issuers automate digital asset workflows across multiple chains at scale: secure, compliant, self-hosted.
- [Quickstart](https://docs.fystack.io/quickstart.md): Get started with the Fystack API: log in to your workspace, create an API key, install the SDK, create your first wallet and make your first deposit.
- [SDKs](https://docs.fystack.io/sdks.md): Official Fystack SDKs for TypeScript and Go that handle request signing, key management, wallets, withdrawals, Web3 signing, and webhook verification.
- [Building with AI](https://docs.fystack.io/building-with-ai.md): Use Fystack docs with AI coding assistants such as Claude Code, Cursor, Codex and ChatGPT through llms.txt, Markdown pages and copy-ready prompts.
- [API Authentication](https://docs.fystack.io/authentication.md): In this guide, we'll look at how authentication works. Fystack API uses HMAC-based authentication to securely verify your API requests.
- [Pagination](https://docs.fystack.io/pagination.md): In this guide, we will look at how to work with paginated responses when querying the Fystack API
- [Errors](https://docs.fystack.io/errors.md): In this guide, we will talk about what happens when something goes wrong while you work with the API.

## APIs

- [APIs](https://docs.fystack.io/apis.md): Overview of the Fystack API: API keys, wallets, transfers, webhooks, checkout, networks, assets, workspaces, and policies.
- [API Keys](https://docs.fystack.io/api-keys.md): How to get the HMAC secret or generate the Ed25519 client key pair used to sign API requests, with OpenSSL or AWS KMS.
- [Wallets](https://docs.fystack.io/wallets.md): This guide explains how to create and manage wallets using the Fystack API.
- [Transfers](https://docs.fystack.io/withdrawals.md): Learn how to initiate and manage transfers from your wallets.
- [Web3 Sign](https://docs.fystack.io/web3-sign.md): Sign messages, typed data, and transactions with Fystack wallets.
- [Webhooks](https://docs.fystack.io/webhooks.md): API reference for Fystack's webhook system.
- [Pay](https://docs.fystack.io/checkout.md): Integrate Fystack's Checkout API to create seamless payment experiences for your users.
- [Networks](https://docs.fystack.io/networks.md): This guide explains how to retrieve and manage blockchain networks using the Fystack API.
- [Assets](https://docs.fystack.io/assets.md): This guide explains how to retrieve and query cryptocurrency assets using the Fystack API.
- [Workspaces](https://docs.fystack.io/workspaces.md): This guide explains how to retrieve workspace statistics and analytics using the Fystack API.
- [Policies](https://docs.fystack.io/policies.md): Learn how Fystack programmable policies evaluate withdrawals, Web3 transfers, contract calls, and message signing, and how to create, validate, approve, and manage policy rules.

## MPCIUM - Distributed MPC cluster

- [Overview](https://docs.fystack.io/mpcium.md): MPCium is a highly resilient, secure MPC engine that implements threshold signature schemes for distributed key management and transaction signing.
- [MPC Node Installation](https://docs.fystack.io/mpcium/installation.md): Learn how to install and set up Mpcium in your environment.
- [MPC Client](https://docs.fystack.io/mpcium/client.md): A TypeScript client for interacting with Mpcium Multi-Party Computation (MPC) service to generate and manage wallets and sign transactions across multiple blockchains.
- [Security](https://docs.fystack.io/mpcium/security.md): Mpcium Security Model
- [Key Backup & Recovery](https://docs.fystack.io/mpcium/backup.md): Learn how to configure automatic backups, recover your MPCIUM database, and integrate with AWS S3 for cloud storage.

## Cosigner - Self-hosted MPC signer

- [Overview](https://docs.fystack.io/cosigner.md): The Fystack Cosigner is a self-hosted MPC participant. It holds one key share on your infrastructure and signs only what your policy approves.
- [Architecture](https://docs.fystack.io/cosigner/architecture.md): Cosigner architecture: components, transport channels, trust boundaries and the MPC session lifecycle.
- [Key Lifecycle & Signing](https://docs.fystack.io/cosigner/signing-flow.md): How the cosigner runs keygen, threshold signing and resharing, and every check it applies before signing.
- [Approval Callback](https://docs.fystack.io/cosigner/approval-callback.md): Approve or reject every cosigner operation from your own server using RS256-signed JWTs.
- [Installation](https://docs.fystack.io/cosigner/installation.md): Install cosigner-cli, verify the signed runtime, pair with Fystack and start the cosigner.
- [Operations](https://docs.fystack.io/cosigner/operations.md): cosigner-cli reference, backups, recovery exports, updates and monitoring.
- [Nitro Enclave Deployment](https://docs.fystack.io/cosigner/nitro-enclave.md): Nitro Enclave deployment for the Fystack Cosigner is coming soon.
- [Security Model](https://docs.fystack.io/cosigner/security.md): Cosigner security model: trust boundaries, authentication, encryption at rest, hardening, audit and supply chain verification.

## Security

- [Security](https://docs.fystack.io/security.md): Overview of Fystack's security architecture: encryption at rest, database integrity, in-memory runtime protection, secret management, MPC wallet security, supply chain security, and deployment hardening.
- [Encryption at Rest](https://docs.fystack.io/security/encryption-at-rest.md): How Fystack protects private keys, seeds, and secrets by encrypting every asset at rest with AES-256-GCM and layered key management.
- [Data Tampering Detection](https://docs.fystack.io/security/database-integrity.md): How Fystack detects database tampering with Ed25519 signatures, SHA-256 hashing, and automated verification to keep wallet data trustworthy.
- [In Memory Runtime encryption](https://docs.fystack.io/security/runtime-key-encryption.md): How Fystack protects sensitive credentials in memory using guarded buffers, zeroization, and runtime policies to prevent memory-based attacks.
- [Secret Store & KMS Integration](https://docs.fystack.io/security/secret-store-kms-integration.md): How Fystack integrates with enterprise-grade secret stores and key management systems to securely manage credentials and signing keys in hardware and cloud environments.
- [MPC Wallet Security](https://docs.fystack.io/security/mpc-security.md): How Fystack implements Multi-Party Computation (MPC) wallet security with threshold signatures, distributed key generation, and secure multi-party signing protocols.
- [Supply Chain Security](https://docs.fystack.io/security/supply-chain-security.md): Overview of how Fystack verifies dependencies, build artifacts, and deployment pipelines to prevent supply chain attacks.
- [Container Security & Build Provenance](https://docs.fystack.io/security/docker-build-hardening.md): How Fystack ensures verifiable, tamper-resistant container builds through SLSA-compliant provenance, keyless cryptographic signing, and public transparency logs.
- [Deployment Best Practices](https://docs.fystack.io/security/deployment-best-practices.md): How Fystack implements secure deployment practices with private network isolation, strict IAM controls, and endpoint detection to protect production infrastructure.

## Optional

- [Full documentation](https://docs.fystack.io/llms-full.txt): every page above in one file
- [Changelog](https://docs.fystack.io/changelog.md): Release notes for every Fystack version, from v0.1.5 to the current release.
- [v0.3.1](https://docs.fystack.io/changelog/v0.3.1.md): Release notes for v0.3.1 including KYT screening with Webacy, detailed webhook delivery logs, workspace creation by owner invitation, and a refreshed dashboard.
- [v0.3.0](https://docs.fystack.io/changelog/v0.3.0.md): Release notes for v0.3.0 including the multi-chain address book, sweep monitoring, plans and usage, workspace-wide MFA enforcement, second factor on every sign-in, and login alerts.
- [v0.2](https://docs.fystack.io/changelog/v0.2.md): Release notes for v0.2 including Approval Groups for multi-signature governance of wallets and policies, Ed25519 Client Key Pair authentication for the API, and API key expiration dates.
- [v0.1.16](https://docs.fystack.io/changelog/v0.1.16.md): Release notes for v0.1.16 including mandatory email verification, a redesigned Withdrawal Center, live multi-signature approval tracking, wallet balance and overview endpoints, and analytics permission scoping.
- [v0.1.15](https://docs.fystack.io/changelog/v0.1.15.md): Release notes for v0.1.15 including Programmable Policy Engine v2, cryptographically signed policy bundles, custom role management, granular per-module permissions, and live policy reload.
- [v0.1.14](https://docs.fystack.io/changelog/v0.1.14.md): Release notes for v0.1.14 including the self-hosted license key system, real-time notifications over Server-Sent Events, API key IP whitelisting, the first wave of role-based access control, and an RFC 8785 canonical JSON signing fix.
- [v0.1.13](https://docs.fystack.io/changelog/v0.1.13.md): Release notes for v0.1.13 including Gas Sponsorship (Auto-Fuel) for EVM, Solana, and TRON, a redesigned multi-withdrawal tracker, per-field permissions for wallet settings, network-scoped wallets, and wallet lifecycle actions.
- [v0.1.12](https://docs.fystack.io/changelog/v0.1.12.md): Release notes for v0.1.12 including passkey-based 2FA, workspace rename and delete, human-readable asset identifiers, and cross-tab session coordination.
- [v0.1.11](https://docs.fystack.io/changelog/v0.1.11.md): Release notes for v0.1.11 including KYT integration, Tron savings, role-based alert policies, and a cancel transaction API.
- [v0.1.10](https://docs.fystack.io/changelog/v0.1.10.md): Release notes for v0.1.10 including Bitcoin support, idempotency keys, withdrawal approvals UI, and the new Alerts module.
- [v0.1.9](https://docs.fystack.io/changelog/v0.1.9.md): Release notes for v0.1.9 including proposer role, withdrawal categories, expense dashboard, balance query improvements, and MPCIUM key derivation enhancements.
- [v0.1.8](https://docs.fystack.io/changelog/v0.1.8.md): Release notes for v0.1.8 including security enhancements, Tron improvements, alert features, and infrastructure upgrades.
- [v0.1.7](https://docs.fystack.io/changelog/v0.1.7.md): Release notes for v0.1.7 including TRON blockchain support, high availability features, and major infrastructure improvements.
- [v0.1.6](https://docs.fystack.io/changelog/v0.1.6.md): Release notes for v0.1.6 including withdrawal improvements, webhook enhancements, and API additions.
- [v0.1.5](https://docs.fystack.io/changelog/v0.1.5.md): Release notes for v0.1.5 including major enhancements, new APIs, improved reliability, and extensive bug fixes.