---
title: Turborepo 1.9
date: 2023/04/11
description: Turborepo 1.9 focuses on improving observability for your task runs to better understand your caching behavior.
tag: "web development"
ogImage: /images/blog/turbo-1-9-0/twitter-card.png
---

# Turborepo 1.9

import { Authors } from '../../components/Authors'
import Badge from '../../components/Badge'
import Date from "../../components/blog/Date";

<Date>
  Monday, April 11th, 2023
</Date>

<Authors authors={[
  'gregsoltis',
  'nathanhammond',
  'tomknickman',
  'anthonyshew',
  'jaredpalmer',
  'mehulkar',
  'chrisolszewski',
  'nicholasyang',
  'alexanderlyon'
]} />

Turborepo 1.9 focuses on improving observability for your task runs to better understand your caching behavior:

- [**Run Summaries**](#view-and-compare-task-runs): Use the `--summarize` flag to generate a summary of your task to compare against previous runs.
- [**Easier Starters**](#bring-your-own-starter): Use the `--example` flag with `npx create-turbo` to start from official Turborepo examples or custom repositories.
- [**Strict Environments** <Badge>Experimental</Badge>](#strict-environments-experimental): Try enabling strict mode to restrict the environment variables your tasks have access to.

Update today by running `npx @turbo/codemod migrate`.

## View and compare task runs

You can now produce a JSON summary of your task run using the `--summarize` flag:

```bash
turbo build --summarize
```

When this flag is enabled, Turborepo will generate a summary in `.turbo/runs/` that contains all the information necessary to understand how `turbo` interpreted your your task's configuration and code.

```bash
Tasks:    3 successful, 3 total
Cached:   0 cached, 3 total
Time:     1.707s
Summary:  /Users/acme/projects/acme/.turbo/runs/2Nn3X6nWDhP9ag8BnmivWRxHpHC.json
```

You can then compare summaries using your favorite JSON diffing tool to understand why you got a cache hit or a cache miss.

Learn more in the [docs](/repo/docs/reference/command-line-reference#--summarize) to learn more.

## Bring your own starter

`create-turbo` now supports starting a new project from any of the official [Turborepo examples](https://github.com/vercel/turbo/tree/main/examples). Get started with an example using a single command:

```bash
npx create-turbo@latest -e kitchen-sink
```

In your terminal UI, choose your preferred package manager and `create-turbo` will automatically convert the chosen example to your package manager of choice.

Additionally, you can use `create-turbo` with custom repository sources, allowing you to re-use your own custom starter or another starter from around the community:

```bash
npx create-turbo -e https://github.com/your-org/turbo-starter
```

## Strict Environments <Badge>Experimental</Badge>

You can now use the `--experimental-env-mode=strict` flag to restrict the environment variables your tasks have access to. Your tasks will only be aware of the variables you explicitly state, creating a safer caching environment.

In `strict` mode, Turborepo will pass environment variables declared in:

- `globalEnv` and `experimentalGlobalPassThroughEnv` to all tasks
- `env` and `experimentalPassThroughEnv` for each task

```json
{
  // Available to all tasks
  "experimentalGlobalPassThroughEnv": ["GLOBAL_VAR_1"],

  // Available to all tasks and invalidates caches
  "globalEnv": ["GLOBAL_VAR_2"],

  "pipeline": {
    "build": {
      // Only available to `build` tasks
      "experimentalPassThroughEnv": ["VAR_1"],

      // Available to `build` task and invalidates caches
      "env": ["VAR_2"]
    }
  }
}
```

In `strict` mode, this configuration will only expose four environment variables to your `build` tasks, helping you catch missing variables earlier in the development process.

`--experimental-env-mode` also supports `loose` and `infer`.

Learn more in the [docs](/repo/docs/reference/command-line-reference#--experimental-env-mode).

## Community

Since releasing [Turborepo v1.8](/blog/turbo-1-8-0) we've seen incredible adoption and community growth:

- [20.5k+ GitHub Stars](https://github.com/vercel/turbo)
- [1.1M weekly NPM downloads](https://www.npmjs.com/package/turbo)
- 64 years of compute time saved through [Remote Caching on Vercel](https://vercel.com/docs/concepts/monorepos/remote-caching)

Turborepo is the result of the combined work of all of its contributors, including our core team.

Thank you for your continued support, feedback, and collaboration to make Turborepo your build tool of choice.
