---
title: How to determine which Vercel Deployment introduced an issue?
description: Process to quickly determine when a deployment issue was introduced using the Vercel CLI
url: "https://vercel.com/kb/guide/how-to-determine-which-vercel-deployment-introduced-an-issue"
published: 2025-11-03
last_updated: 2025-11-10
authors: Holden Altaffer
install_vercel_plugin: npx plugins add vercel/vercel-plugin
---

With Vercel Preview Deployments and [bisecting](https://vercel.com/docs/cli/bisect), you can quickly and efficiently determine which commit introduced a regression in your application, and then [instantly rollback](https://vercel.com/docs/concepts/deployments/instant-rollback).

[Watch a video tutorial](https://www.youtube.com/watch?v=6CTdji6s1GQ) or learn more in the following guide.

```bash
vercel bisect
```

## Use Vercel Bisect to find first broken deployment

Vercel Bisect is a command, inspired by the [git bisect](https://git-scm.com/docs/git-bisect) command, that helps identify the first Deployment an issue was introduced by traversing a range of preview deployments, marking them as either "good" or "bad". This tool was released in version 24 of the CLI.

To start your debugging session, run `vc bisect` in the terminal and you will be given an interactive prompt to help find where the bad commit was introduced. Start with a deployment URL where the bug occurs. Next, specify a deployment URL where the bug does _not_ occur. Lastly, specify a subpath to narrow down by page, such as `/login` or `/`.

Vercel Bisect will retrieve a list of deployments for you to review, starting in the middle of the list, utilizing a [Binary Search](https://en.wikipedia.org/wiki/Binary_search_algorithm). At each step, you’ll indicate if the deployment is “good” or “bad” to quickly narrow down to the root cause The number of steps left will be visible. After the full list of deployments has been traversed, the first bad deployment will be shown with the date, commit with message, and URL to inspect the deployment on the dashboard.

You can then [instantly rollback to a previous deployment](https://vercel.com/docs/concepts/deployments/instant-rollback) with Vercel.

## Related Documentation

- [Vercel CLI](https://vercel.com/docs/cli)

## More Vercel CLI guides

- [The Complete Guide to Vercel Connect](/kb/guide/vercel-connect): Use Vercel Connect to call provider APIs like Slack, GitHub, Linear, Microsoft, Discord, Snowflake, and Salesforce from your agents and services with short-lived, scoped tokens instead of long-lived secrets.
- [Does Vercel support Docker deployments?](/kb/guide/does-vercel-support-docker-deployments): Vercel supports deploying OCI-compatible container images through Vercel Functions and Vercel Container Registry, with Active CPU pricing and automatic scaling.
- [How can I run end-to-end tests after my Vercel Preview Deployment?](/kb/guide/how-can-i-run-end-to-end-tests-after-my-vercel-preview-deployment): Learn how to use the Vercel CLI in combination with your CI/CD provider to run end-to-end tests for every code change.

## Reference Architecture

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- [Agent stack](/kb/architecture/agents): Build and operate agents with models, tools, and durable workflows.
- [Web applications](/kb/architecture/web): Choose rendering, data, authentication, and caching approaches.
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