Self-Custody Lightning Wallets
Give your users real Lightning payments with real self-custody. No nodes, no channels, no liquidity headaches: just instant Bitcoin that users actually control.
Trusted by teams like Tether, Breez, and Xverse building on Spark
Lightning wallets forced a choice between speed and sovereignty
Self-custodial Lightning means running infrastructure: nodes, channels, inbound liquidity, watchtowers, backup complexity. Most teams that want to offer Lightning end up going custodial because the operational burden of doing it properly is too high. The ones that stay self-custodial ship a worse UX: failed payments, capacity limits, channel management pushed onto users, and no stablecoin support. Your users shouldn't have to choose between controlling their money and having it work.
What we do
One SDK for Lightning, self-custody, and stablecoins
No nodes, no channels, no ops
Traditional Lightning means running nodes, managing channels, provisioning inbound liquidity, and handling routing failures. Spark collapses all of that into a single SDK call. You get full Lightning send and receive without any of the infrastructure.
Self-custodial out of the box
Users hold their own keys. You never touch funds, never take on custodial risk. The SDK handles key generation, backup, and recovery: you get the UX of a managed wallet with a self-custodial security model.
Instant bitcoin deposits
On-chain bitcoin credits immediately with 0-conf. Users send to their address and see it in seconds, not blocks. No pending states, no 10-minute waits, no confused support tickets.
Bitcoin and stablecoins in one integration
BTC, USDT, and USDB live natively on Spark in the same wallet. One SDK gives your users bitcoin and stablecoins together: no bridges, no wrapped tokens, no separate chain to integrate.
Why Spark
Self-custodial Lightning without the operational burden
Users hold their own keys from day one
Spark wallets are self-custodial by default. Key generation, backup, and recovery are handled by the SDK. You never touch user funds and never take on custodial risk.
Lightning works without infrastructure
No nodes, no channels, no watchtowers, no liquidity provisioning. Spark provides full Lightning send and receive through a single SDK integration. The protocol handles everything that used to require ops teams.
On-chain and Lightning in one balance
Users receive on-chain bitcoin (credited instantly via 0-conf) and Lightning payments into the same wallet. No separate balances, no manual channel funding, no user-facing complexity.
Add stablecoins without adding chains
BTC, USDT, and USDB all live in the same Spark wallet. One integration gives your users bitcoin and stablecoins: no bridges, no wrapped tokens, no second infrastructure stack.
Ship fast, scale without ops
The Spark SDK runs on mobile, web, and server. A few lines of code to initialize a wallet. No infrastructure to maintain as your user base grows.
Case study
Self-custody Lightning is so back
The biggest Lightning wallet integrated Spark to bring self-custodial Lightning to their users for the first time, re-entering the U.S. market with a fully non-custodial experience.
Read case studyProducts
Instant Bitcoin Deposits
Receive on-chain bitcoin in seconds with 0-conf
Self-Custodial Lightning
Full Lightning send and receive, no nodes or channels
Bitcoin Buy and Sell
The cheapest way to buy and sell bitcoin directly to a self-custodial wallet
Bitcoin Rewards
Distribute bitcoin rewards and incentives at scale
Cross-Chain Bitcoin Swaps
The fastest, cheapest way to move bitcoin into stablecoins and other assets
Stablecoin Issuance
Issue and manage stablecoins natively on Bitcoin
Trusted by the world's best self-custody teams.
From wallets to stablecoin issuers, the best teams ship on Spark.Spark and WDK unlock programmable, resilient Bitcoin over Lightning: instant global payments without compromising custody or privacy.
We care deeply about network effects. Issuing on Spark is a no-brainer for Brale, it has the potential to bring billions of people to stablecoins.
Our goal is to make Xverse the definitive home of BitcoinFi, and integrating Spark is a monumental step.
Spark is transformative. It redefines what Bitcoin can be, evolving it from a monetary network into an application platform.
We're excited to build on Spark to unlock powerful Bitcoin-based rails for all the users we serve without requiring them to be crypto-native.
Flashnet couldn't exist without Spark. It's the best infrastructure for building real money apps on Bitcoin, period.
FAQ
Yes. Users hold their own private keys and can always exit to Bitcoin L1. Spark uses a trust-minimized architecture: it's not perfectly trustless, but users retain control of their funds and unilateral exit rights.
Traditional self-custodial Lightning requires nodes, channels, and liquidity management. Spark eliminates all of that. Your users get instant Lightning payments with full self-custody, and you get a single SDK instead of an infrastructure stack.
Users can exit to Bitcoin L1. Spark is designed so that funds are recoverable: users retain unilateral exit rights, similar to how Lightning channels work.
Yes. Unlike traditional Lightning, Spark supports offline receive. Payments are held securely and credited when the user comes back online.
The SDK handles key backup and recovery. Users can back up with seed phrases, or you can integrate your own auth flow (passkeys, social login) for a seamless UX.
Build a Lightning wallet without running Lightning
Spark handles the protocol complexity so you can ship a self-custodial Lightning wallet that actually works.