# Incremental migration

> Move from ansi-escapes, terminal-link and term-img one import at a time, and from term-img's paths to bytes with one readFile.

Source: https://paratext.interlace.tools/docs/recipes/incremental-migration

Each drop-in is graded on its own, so a program can move one import at a time and ship in
between.

## One import at a time

```diff
- import ansiEscapes, { cursorTo, eraseLines, link } from 'ansi-escapes';
+ import ansiEscapes, { cursorTo, eraseLines, link } from 'paratext';
- import terminalLink from 'terminal-link';
+ import terminalLink from 'paratext/terminal-link';
- import terminalImage from 'term-img';
+ import terminalImage from 'paratext/term-img';
```

Or let the codemod do it: `npx burgee migrate --dry-run` lists every import it would rewrite —
only drop-ins graded level with their incumbent, so ansi-escapes and terminal-link and not
term-img — and `npx burgee migrate` rewrites them
([Migrate](https://burgee.interlace.tools/docs/migrate)).

## term-img: bytes instead of a path

`paratext/term-img` takes bytes. Where you passed a path, read it first:

```diff
+ import { readFile } from 'node:fs/promises';
- terminalImage('logo.png');
+ terminalImage(await readFile('logo.png'));
```

## What changes after the move

The ansi-escapes CSI calls are byte-for-byte what they were. `link`, `image` and `setCwd` now
write their text form on a pipe instead of escape bytes, which is the reason to move
([Compatibility](/docs/drop-ins#known-differences)). terminal-link and term-img keep their
incumbents' detection and fallbacks.

## Checking each step

```bash
npm uninstall ansi-escapes terminal-link term-img
npm ls ansi-escapes
```

`npm ls` shows what still pulls ansi-escapes in transitively — log-update and terminal-link
both depend on it.