Argument of type 'string' is not assignable to parameter of type 'RedirectType | undefined' #88627
Description
Link to the code that reproduces this issue
https://github.com/typeofweb/redirect-next-reproduction
To Reproduce
- Open the codebase
- Look at
/app/page.tsx
Current vs. Expected behavior
Currenty behavior
app/page.tsx:4:28 - error TS2345: Argument of type 'string' is not assignable to parameter of type 'RedirectType | undefined'.
4 return redirect("/admin", RedirectType.replace);
~~~~~~~~~~~~~~~~~~~~
Found 1 error in app/page.tsx:4
Expected behavior
No errors.
Provide environment information
Operating System:
Platform: darwin
Arch: arm64
Version: Darwin Kernel Version 25.3.0: Fri Dec 5 23:12:37 PST 2025; root:xnu-12377.80.260.0.1~42/RELEASE_ARM64_T6041
Available memory (MB): 49152
Available CPU cores: 14
Binaries:
Node: 22.17.1
npm: 10.9.2
Yarn: N/A
pnpm: 10.26.0
Relevant Packages:
next: 16.1.1-canary.29 // Latest available version is detected (16.1.1-canary.29).
eslint-config-next: N/A
react: 19.3.0-canary-bb8a76c6-20260115
react-dom: 19.3.0-canary-bb8a76c6-20260115
typescript: 5.9.3
Next.js Config:
output: N/AWhich area(s) are affected? (Select all that apply)
TypeScript
Which stage(s) are affected? (Select all that apply)
next dev (local), next build (local), next start (local), Vercel (Deployed)
Additional context
This works fine in canary-27 and is broken in canary-28.