Next.js Performance6 min read2026-09-18

Why a replaced image can stay stale after a Next.js deployment

Replacing a file inside public with a new image does not always change the URL. Browsers, CDNs and image optimizers can therefore keep serving the earlier response even though the deployment succeeded.

The URL is part of the cache key

A public path such as /images/work/project.png can keep the same address across deployments. If an upstream cache considers that response fresh, replacing the bytes alone may not invalidate it.

Use static imports for build-time screenshots

When an image is imported from source code, Next.js emits a content-hashed asset. Replacing the image produces a different output filename, so a new deployment naturally references a new URL.

Import local images into the content configuration
Let Next/Image generate responsive formats
Avoid manually cache-busting stable public URLs

Still clean the build output

A clean .next directory prevents an older local build from being reused by the CI job. Your deployment process should also copy both the standalone server and .next/static assets when using standalone output.

The URL is part of the cache key

Use static imports for build-time screenshots

Still clean the build output

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