Mempool address balance updates

This library computes balance updates for a given BTC address.

The data source is the mempool.js confirmed transactions history for that address.

The focus is not to track the total balance, but its delta updates over time. Useful for analytics and market impact analysis.

Why is this needed?

A wallet balance is actually the sum of the UTXOs controlled by the wallet's private keys.

UTXO stands for Unspent Transaction (TX) Output. Every on-chain transaction sends BTC to one or more addresses, from at least zero (in case of a coinbase transcation) addresses.

An UTXO must be fully consumed, otherwise the sender loses the rest. So it is often seen that the sender sends BTC to a recipient, and sends the rest of the UTXO (change) back to its own address.

It is also possible to build elaborate unlock schemes such as multi sig: this is out of scope.

See https://en.bitcoin.it/wiki/Transaction

Developer guide: TSDX

Commands

TSDX scaffolds your new library inside /src.

To run TSDX, use:

npm start # or yarn start

This builds to /dist and runs the project in watch mode so any edits you save inside src causes a rebuild to /dist.

To do a one-off build, use npm run build or yarn build.

To run tests, use npm test or yarn test.

Configuration

Code quality is set up for you with prettier, husky, and lint-staged. Adjust the respective fields in package.json accordingly.

Jest

Jest tests are set up to run with npm test or yarn test.

Bundle Analysis

size-limit is set up to calculate the real cost of your library with npm run size and visualize the bundle with npm run analyze.

Setup Files

This is the folder structure we set up for you:

/src
  index.tsx       # EDIT THIS
/test
  blah.test.tsx   # EDIT THIS
.gitignore
package.json
README.md         # EDIT THIS
tsconfig.json

Rollup

TSDX uses Rollup as a bundler and generates multiple rollup configs for various module formats and build settings. See Optimizations for details.

TypeScript

tsconfig.json is set up to interpret dom and esnext types, as well as react for jsx. Adjust according to your needs.

Continuous Integration

GitHub Actions

Two actions are added by default:

• main which installs deps w/ cache, lints, tests, and builds on all pushes against a Node and OS matrix
• size which comments cost comparison of your library on every pull request using size-limit

Optimizations

Please see the main tsdx optimizations docs. In particular, know that you can take advantage of development-only optimizations:

// ./types/index.d.ts
declare var __DEV__: boolean;

// inside your code...
if (__DEV__) {
  console.log('foo');
}

You can also choose to install and use invariant and warning functions.

Module Formats

CJS, ESModules, and UMD module formats are supported.

The appropriate paths are configured in package.json and dist/index.js accordingly. Please report if any issues are found.

Named Exports

Per Palmer Group guidelines, always use named exports. Code split inside your React app instead of your React library.

Including Styles

There are many ways to ship styles, including with CSS-in-JS. TSDX has no opinion on this, configure how you like.

For vanilla CSS, you can include it at the root directory and add it to the files section in your package.json, so that it can be imported separately by your users and run through their bundler's loader.

Publishing to NPM

We recommend using np.