#13180·next-auth

Unable to resolve dependency tree when updating to Nodemailer V7

Author: stanlee786Created Aug 20, 2025Updated May 31, 2026
Labelsbugtriage

Environment

System: OS: Linux 6.16 Arch Linux CPU: (12) x64 AMD Ryzen 5 7640U w/ Radeon 760M Graphics Memory: 8.82 GB / 14.93 GB Container: Yes Shell: 4.0.2 - /usr/bin/fish Binaries: Node: 22.18.0 - ~/.local/share/nvm/v22.18.0/bin/node npm: 11.5.2 - ~/.local/share/nvm/v22.18.0/bin/npm npmPackages: next: ^15.5 => 15.5.0 next-auth: ^4.24 => 4.24.11 react: ^19.1 => 19.1.1

Reproduction URL

https://github.com/stanlee786/next-auth-example

Describe the issue

When trying to update from Nodemailer V6 to V7, I get the following error:

bash
npm warn ERESOLVE overriding peer dependency
npm error code ERESOLVE
npm error ERESOLVE could not resolve
npm error
npm error While resolving: [email protected]
npm error Found: [email protected]
npm error node_modules/nodemailer
npm error   peerOptional nodemailer@"^6.8.0" from @auth/[email protected]
npm error   node_modules/next-auth/node_modules/@auth/core
npm error     @auth/core@"0.40.0" from [email protected]
npm error     node_modules/next-auth
npm error       next-auth@"beta" from the root project
npm error
npm error Could not resolve dependency:
npm error peerOptional nodemailer@"^6.6.5" from [email protected]
npm error node_modules/next-auth
npm error   next-auth@"beta" from the root project
npm error
npm error Conflicting peer dependency: [email protected]
npm error node_modules/nodemailer
npm error   peerOptional nodemailer@"^6.6.5" from [email protected]
npm error   node_modules/next-auth
npm error     next-auth@"beta" from the root project
npm error
npm error Fix the upstream dependency conflict, or retry
npm error this command with --force or --legacy-peer-deps
npm error to accept an incorrect (and potentially broken) dependency resolution.

Nodemailer V7 contains the following breaking change:

  • SESv2 SDK support, removed older SES SDK v2 and v3 , removed SES rate limiting and idling features

How to reproduce

Try updating Nodemailer V6 to V7 in a Next.js 15 environment configured with NextAuth. Alternatively you can try installing Nodemailer V7, this will have the same result.

Expected behavior

Latest NextAuth version to support Nodemailer V7 and update without error.