Minimal reproduction for an rspack production-build panic:

RealContentHashPlugin: circular hash dependency

yarn install
yarn build:mf

Expected output:

crates/rspack_plugin_real_content_hash/src/lib.rs:464:9
RealContentHashPlugin: circular hash dependency

RealContentHashPlugin scans asset contents for provisional [contenthash] strings and topologically sorts them for replacement. When multiple async chunks each embed the same chunk-id→hash map (as production MF remotes do via __webpack_require__.u), every chunk references every other chunk's hash while also owning its own → topological sort fails.

This repo uses:

1. A small MF remote (entry: {}, 10 exposes, 200 lazy async chunks by default).
2. output.chunkFilename: 'chunks/[id]/chunk-[contenthash].js' with optimization.realContentHash: true.
3. DuplicateChunkHashMapPlugin — copies the container's hash map into 2 async chunks at stage PROCESS_ASSETS_STAGE_OPTIMIZE_HASH - 1, matching the multi-runtime structure observed in production (~10 chunks there; 2 is enough to form a cycle).

Without step 3, standalone MF builds only put the full map in the container entry and do not panic.

FEATURE_COUNT=10 LAZY_PER_FEATURE=20 DUPLICATE_COUNT=2 yarn build:mf

REAL_CONTENT_HASH=false yarn build:mf
# or use [chunkhash] in async chunkFilename instead of [contenthash]

MIT