The bdk-wasm
library aims at providing access to the excellent BitcoinDevKit to JS and Node environments (and eventually any device supporting WebAssembly).
It specializes in compiling BDK on the wasm32-unknown-unknown
target and use wasm-bindgen
to create TypeScript bindings.
This repo handles the packaging and publishing of the bitcoindevkit
NPM package, using wasm-pack
.
This library offers all the desired functionality to build a Bitcoin wallet out of the box:
- UTXO management
- Coin selection
- Wallet upates by syncing and scanning the chain data
- Bitcoin descriptors for flexibility in the definition of spending conditions. Supports all address types from legacy to Taproot.
- State update and persistence
- Transaction creation, signing and broadcasting
- Dynamic addresses
- and much more
For a lightweight library providing stateless utility functions, see bitcoinjs
.
yarn add bitcoindevkit
Warning
There are several limitations to using BDK in WASM. Basically any functionality that requires the OS standard library is not directly available in WASM. However, there are viable workarounds documented below. Some key limitations include:
- No access to the file system
- Network access is limited to http(s)
With no direct access to the file system, persistence cannot be handled by BDK directly. Instead, an in memory wallet must be used in the WASM environment, and the data must be exported using wallet.take_staged()
. This will export the changeset for the updates to the wallet state, which must then be merged with current wallet state in JS (will depend on your persistence strategy). The persisted ChangeSet
can be passed to wallet.load()
to recover the wallet.
This essentially means the library only supports Esplora as blockchain client. Both RPC and Electrum clients require sockets and will not work for BDK in a WASM environment out of the box.
Refers to this section.
Important
You need the wasm32-unknown-unknown
toolchain to be installed:
rustup target add wasm32-unknown-unknown
wasm-pack build
Choose your desired features when building:
--features "esplora"
wasm-pack test --headless --firefox
Works with
--firefox
,--chrome
or--safari
.
Licensed under either of
- Apache License, Version 2.0, (LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or https://opensource.org/licenses/MIT)
at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.