How does Atlas handle Next.js specific configurations during upgrades?

Atlas understands Next.js project structures, including `next.config.js` and the `app` directory. It can read these files and propose changes that respect server/client boundaries, always presenting a unified diff for your explicit approval before writing.

Can Atlas upgrade Next.js itself to a new major version?

Yes, Atlas can upgrade Next.js to a new major version. It uses `pnpm` to perform the upgrade and then systematically addresses any resulting compile or test failures, just like any other dependency, by reading compiler output and running `Vitest with React Testing Library`.

What testing tools does Atlas integrate with for Next.js?

Atlas integrates directly with `Vitest with React Testing Library`, running your existing test suite via `pnpm test` to validate fixes and ensure the upgraded Next.js application remains functional. It uses the `bash` tool to execute these commands.

How does Atlas ensure code quality after a Next.js dependency upgrade?

Atlas ensures code quality by iteratively running `pnpm build` and `pnpm test` until all errors are resolved. It also respects your project's `prettier` configuration, ensuring formatting consistency, and presents all changes as a diff for review.

Is it safe to let Atlas modify my Next.js codebase?

Yes, Atlas is designed for safety. Every tool call is permission-gated against allow, ask, and deny rules, and all proposed file edits, including those to `next.config.js` or `app` routes, are presented as a unified diff for your explicit approval before being written.

How does Atlas get context on breaking changes for Next.js libraries?

Atlas uses the `webfetch` tool to retrieve official release notes and changelogs directly from the library's documentation. This ensures that fixes for your Next.js project are based on accurate, up-to-date information, rather than assumptions about breaking changes.

Can Atlas handle complex Next.js monorepo upgrades?

While the context does not explicitly detail monorepo support, Atlas's ability to drive `pnpm` and read real compiler output means it can operate within any Next.js project structure where `pnpm` and `next.config` are present, addressing issues across multiple packages if configured.

Upgrade a Next.js Dependency and Fix Breakage with Atlas in 2026

In 2026, upgrading a major dependency in a Next.js project and fixing all resulting compile and test failures is streamlined with Atlas, which directly interacts with your `pnpm` package manager, reads `next.config` files, and leverages `Vitest with React Testing Library` for validation. Atlas drives the entire process from upgrade to commit.

How Atlas upgrades Next.js dependencies and fixes compile errors

Atlas streamlines dependency upgrades in Next.js projects by directly invoking `pnpm` to bump versions, then reading the actual compiler output to identify and resolve breakage. This process ensures that in 2026, developers can confidently update critical libraries like React or Next.js itself.

Atlas initiates the dependency upgrade by executing `pnpm upgrade <package-name>@latest` through its `bash` tool. It captures the complete output, which can be extensive, saving it to a file if it exceeds terminal limits for later review using the `read` tool. Once the upgrade is complete, Atlas runs `pnpm build` to compile the Next.js application and capture all compiler errors. Instead of guessing, Atlas uses this real-time feedback to identify specific breakage points. For each error, Atlas employs its `edit` tool to modify the relevant Next.js files, such as those within the `app` directory or API routes. It leverages the `lsp` tool's `goToDefinition` operation to inspect the new signatures and types in the upgraded package, ensuring fixes are precise and align with the new API. This iterative process of building and fixing continues until the Next.js project compiles without errors.

Accessing Next.js release notes and changelogs with Atlas

To accurately fix breaking changes in a Next.js dependency upgrade, Atlas uses `webfetch` to retrieve the library's release notes and changelogs. This ensures that in 2026, fixes align precisely with documented changes, preventing guesswork and accelerating the migration process.

When a major version upgrade introduces breaking changes, understanding the official migration path is crucial. Atlas addresses this by using its `webfetch` tool to pull the release notes and changelogs directly from the upgraded library's documentation. This provides the agent with the necessary context to understand the breaking changes and how to properly adapt the Next.js codebase. For instance, if a core React library used within Next.js components changes its API, Atlas can fetch the official React changelog. This information guides the `edit` tool's operations, ensuring that modifications to Next.js components, server components, or API routes correctly implement the new patterns and avoid introducing new issues. This direct access to authoritative documentation makes the migration process more reliable and efficient.

Validating Next.js fixes with Vitest and real-time feedback

After applying fixes, Atlas validates the Next.js codebase by repeatedly running `Vitest with React Testing Library` and the `pnpm build` command. This iterative approach ensures that by 2026, all compile and test failures are resolved, providing immediate feedback on every change.

Once compile errors are addressed, Atlas moves to validate the functional correctness of the Next.js application. It executes the project's test suite by running `pnpm test` through the `bash` tool, which in a Next.js project typically invokes `Vitest with React Testing Library`. Atlas captures the output of these tests, identifying any failures. Similar to compile errors, test failures provide concrete feedback on areas that still require attention. Atlas then uses its `edit` tool to modify the relevant Next.js components, hooks, or utility functions to resolve these test failures. The `lsp` tool can again be used to inspect types and definitions within the upgraded package to ensure correct usage. This cycle of running `pnpm build`, `pnpm test`, and applying fixes with `edit` continues until both the build is clean and all `Vitest with React Testing Library` tests pass, ensuring the Next.js application is fully functional and stable after the upgrade.

Reviewing and committing Next.js dependency upgrades with Atlas

Atlas ensures safety and transparency in Next.js dependency upgrades by presenting a unified diff of all file edits for approval before writing. In 2026, developers can review every change, including modifications to `next.config.js` or `app` routes, and then stage and commit directly.

Before any changes are permanently written to your Next.js project, Atlas computes a unified diff for every file it has modified. This includes changes to `next.config.js`, files within the `app` directory, server components, client components, and API routes. This comprehensive diff is surfaced for your explicit approval, giving you full control over the outcome. Every Atlas tool call is permission-gated, meaning you must allow, ask, or deny its execution. This ensures that no changes are made without your consent. Atlas also snapshots file changes as git patches, allowing edits to be easily diffed and rolled back if necessary. Once you approve the changes, Atlas can read your git branches and status, and then stage the modified files and create a commit on your behalf, completing the dependency upgrade workflow in a secure and transparent manner.

Step by step

01Initiate the dependency upgrade in your Next.js project by asking Atlas to run `pnpm upgrade <package-name>@latest` using the `bash` tool, capturing the full output.
02Instruct Atlas to fetch the upgraded library's release notes and changelog using the `webfetch` tool, providing context for breaking changes.
03Ask Atlas to run `pnpm build` via the `bash` tool to enumerate compile-time breakage in your Next.js application, reading the output for errors.
04Fix each identified error in your Next.js files using the `edit` tool, leveraging `lsp`'s `goToDefinition` to inspect new signatures in the upgraded package.
05Iteratively re-run `pnpm build` and `pnpm test` (which executes `Vitest with React Testing Library`) with the `bash` tool until all compile and test failures are resolved.
06Review the unified diff of all changes, including modifications to `next.config.js` or `app` routes, presented by Atlas before approving the writes.
07Approve the changes and ask Atlas to stage and create a commit for the Next.js dependency upgrade.

Frequently asked questions

How does Atlas handle Next.js specific configurations during upgrades?: Atlas understands Next.js project structures, including `next.config.js` and the `app` directory. It can read these files and propose changes that respect server/client boundaries, always presenting a unified diff for your explicit approval before writing.
Can Atlas upgrade Next.js itself to a new major version?: Yes, Atlas can upgrade Next.js to a new major version. It uses `pnpm` to perform the upgrade and then systematically addresses any resulting compile or test failures, just like any other dependency, by reading compiler output and running `Vitest with React Testing Library`.
What testing tools does Atlas integrate with for Next.js?: Atlas integrates directly with `Vitest with React Testing Library`, running your existing test suite via `pnpm test` to validate fixes and ensure the upgraded Next.js application remains functional. It uses the `bash` tool to execute these commands.
How does Atlas ensure code quality after a Next.js dependency upgrade?: Atlas ensures code quality by iteratively running `pnpm build` and `pnpm test` until all errors are resolved. It also respects your project's `prettier` configuration, ensuring formatting consistency, and presents all changes as a diff for review.
Is it safe to let Atlas modify my Next.js codebase?: Yes, Atlas is designed for safety. Every tool call is permission-gated against allow, ask, and deny rules, and all proposed file edits, including those to `next.config.js` or `app` routes, are presented as a unified diff for your explicit approval before being written.
How does Atlas get context on breaking changes for Next.js libraries?: Atlas uses the `webfetch` tool to retrieve official release notes and changelogs directly from the library's documentation. This ensures that fixes for your Next.js project are based on accurate, up-to-date information, rather than assumptions about breaking changes.
Can Atlas handle complex Next.js monorepo upgrades?: While the context does not explicitly detail monorepo support, Atlas's ability to drive `pnpm` and read real compiler output means it can operate within any Next.js project structure where `pnpm` and `next.config` are present, addressing issues across multiple packages if configured.

Try Atlas in your terminal

The terminal-native AI coding agent. Free core, single binary.

Install Atlas

Related guides

Upgrade a Dependency and Fix the Breakage with Atlas (2026 Workflow)

How to upgrade a dependency and fix the breakage with Atlas in 2026: bash drives the package manager, webfetch pulls the release notes, edit fixes each compiler error.

Atlas for Next.js in 2026

Adopt Atlas, the terminal-native AI coding agent, for Next.js development in 2026. Enhance productivity across App Router, server components, and API routes with secure, reviewable AI assistance.

Self-review your working diff before committing in Next.js with Atlas in 2026

Next.js developers in 2026 use Atlas to self-review uncommitted diffs, catching mistakes before CI. Leverage Vitest, prettier, and pnpm with Atlas's AI agent.

Research a Third-Party API Before Integrating It in Next.js with Atlas (2026 Guide)

Pull a live API's real shape into context before writing a Next.js route handler: Atlas websearch, webfetch, grep, then pnpm, Vitest with React Testing Library.

Write Unit Tests for Untested Next.js Code with Atlas in 2026

In 2026, Atlas helps Next.js developers write unit tests for untested code using Vitest and React Testing Library. Automate test generation, match existing conventions, and ensure code quality in your Next.js projects

Debug a Single Failing Test in Next.js with Atlas in 2026

In 2026, Atlas helps Next.js developers efficiently debug single failing tests using Vitest with React Testing Library and pnpm. Pinpoint issues in your Next.js codebase with AI-driven precision.

Trace a runtime bug from a stack trace in Next.js with Atlas in 2026

Pinpoint and fix Next.js runtime bugs from production stack traces without a debugger. Atlas leverages its AI tools to navigate your Next.js codebase, identify root causes, and propose fixes with `Vitest with React

Refactor a Legacy Next.js Module with Atlas in 2026

Streamline your Next.js codebase in 2026 by refactoring legacy modules with Atlas. Maintain behavior and prevent breaking changes across your App Router and API routes.

Browse this resource hub