Won´t start in a docker container

[Arcade1080]

Given this docker image:

ARG NODE_VERSION
ARG BUILDER

FROM ${BUILDER} as build

WORKDIR /usr/src/build

RUN yarn workspace website build

RUN yarn workspaces focus website --production


FROM node:${NODE_VERSION}-alpine as website

ARG NODE_ENV

ENV NODE_ENV=${NODE_ENV}

WORKDIR /usr/app

RUN npm install -g pm2@4.5.6

COPY --from=build --chown=node:node /usr/src/build/node_modules ./node_modules
COPY --from=build --chown=node:node /usr/src/build/packages/website/package.json ./
COPY --from=build --chown=node:node /usr/src/build/packages/website/.next ./.next
COPY --from=build --chown=node:node /usr/src/build/packages/website/public ./public
COPY --from=build --chown=node:node /usr/src/build/packages/website/next.config.mjs ./
COPY --from=build --chown=node:node /usr/src/build/packages/website/theme.config.jsx ./
COPY --chown=node:node ./process.yml ./

RUN mkdir -p .next/cache/images && chown node:node .next/cache/images

USER node

EXPOSE 5002

CMD [ "pm2-runtime", "/usr/app/process.yml"]

(process.yml starts nextra w/ "npm run start")

The container displays this error message (via docker logs ..) after starting:

⨯ Failed to load next.config.mjs, see more info here https://nextjs.org/docs/messages/next-config-error Error: > Couldn't find any pagesorapp directory. Please create one under the project root at findPagesDir (/usr/app/node_modules/next/dist/lib/find-pages-dir.js:42:15) at findPagesDirectory (/usr/app/node_modules/nextra/dist/index.js:169:15) at Object.<anonymous> (/usr/app/node_modules/nextra/dist/index.js:173:53) at Module._compile (node:internal/modules/cjs/loader:1375:14) at Module._extensions..js (node:internal/modules/cjs/loader:1434:10) at Module.load (node:internal/modules/cjs/loader:1206:32) at Module._load (node:internal/modules/cjs/loader:1022:12) at cjsLoader (node:internal/modules/esm/translators:358:17) at ModuleWrap.<anonymous> (node:internal/modules/esm/translators:307:7) at ModuleJob.run (node:internal/modules/esm/module_job:218:25)

This is the next.config.mjs:

/** @type {import('next').NextConfig} */
const nextConfig = {
  pageExtensions: ["js", "jsx", "ts", "tsx", "mdx"],
};

import nextra from "nextra";

const withNextra = nextra({
  theme: "nextra-theme-docs",
  themeConfig: "./theme.config.jsx",
});

export default withNextra(nextConfig);

Any help would be much appreciated.