Fystack builds custody infrastructure that helps businesses automate their digital asset workflows, payments, treasury, payouts, and settlements - efficiently and at a fraction of the cost of traditional custodians.
We support multiple key management approaches including MPC threshold signing (keys never exist in one place), standard HD wallets, and AWS KMS integration so teams can choose the security model that fits their needs.
What you can build with Fystack:
Why teams choose Fystack:
An open-source MPC engine that lets teams run their own secure node cluster for distributed key management and transaction signing. Private keys are not stored or reconstructed in one place, with a threshold signing scheme requiring consensus across nodes before any operation executes.
Built for on/off-ramp providers, stablecoin payment platforms, OTC desks, and crypto neobanks that need full control over their keys, Fystack's custody platform gives teams production-ready wallet and key management. Combining MPC vaults for secure long-term storage with high-throughput wallets built for scale, Fystack supports 10+ blockchains with the capacity to manage over 10,000 wallets and process $500,000 in monthly transfer volume.
Fystack's crypto payment gateway lets businesses accept and process digital asset payments across multiple blockchains through a single integration. It detects incoming deposits in real time, automates settlement flows, and handles the full transaction lifecycle with auditability built in.
Production-ready for exchanges, payment gateways, and OTC desks monitoring high volumes of deposit addresses, Fystack offers an open-source indexer that detects deposits across 12+ blockchains in real time: parsing onchain transactions, matching destination addresses with sub-millisecond lookups, and streaming results for downstream processing.
Fystack's white-label solution lets businesses launch a fully branded digital asset custody product with wallet management, transaction controls, and compliance tooling under their own brand.
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