Re-map import paths

The imports field in deno.json is an import map: any specifier prefix can be re-mapped to any location. Besides naming packages, it replaces the paths section of tsconfig.json for path aliases like @/.

Alias a directory Jump to heading#

A key ending in / maps a whole prefix. The common convention aliases the source root:

{
  "imports": {
    "@/": "./src/"
  }
}

Imports anywhere in the project can now address files from the root instead of counting ../ segments:

import { greet } from "@/greet.ts";

Alias a single module Jump to heading#

A key without a trailing slash maps one bare name to one file, which reads nicely for modules used everywhere:

{
  "imports": {
    "@/": "./src/",
    "logger": "./src/utils/logger.ts"
  }
}

import { greet } from "@/greet.ts";
import { log } from "logger";

log(greet("import maps"));

$ deno run main.ts
[log] Hello, import maps!

Editor support Jump to heading#

The Deno language server reads the same file, so completions and go-to-definition follow the aliases with no extra tsconfig.json configuration. If you migrate a project that has compilerOptions.paths, move those entries into imports.

Scoped overrides Jump to heading#

The standard import map scopes field also works, remapping a specifier only for imports that originate under a given path prefix:

{
  "imports": {
    "logger": "./src/utils/logger.ts"
  },
  "scopes": {
    "./vendor/": {
      "logger": "./vendor/legacy_logger.ts"
    }
  }
}

Modules under vendor/ get the legacy logger; everything else gets the default.

For how packages themselves are named and versioned in the import map, see Add and remove dependencies and the modules documentation.