Umbrella tracker for open issues caused or shaped by how Rolldown forms output chunks — cross-chunk execution order, inter-chunk cycles, cross-chunk init/binding wiring, chunk count/quality, chunk-graph parity vs Rollup, and the manual-chunking (advancedChunks / codeSplitting / preserveModules) surface. It spans rolldown/rolldown and the Rolldown-era vitejs/vite issues that surface these.

38 open (33 rolldown, 5 vite). Grouped by nature below; a priority-sorted view is in the collapsed section at the end. Last synced 2026-06-30.

correctness/execution-order (3)

Cross-chunk side-effects/modules emitted in the wrong run order; code runs before its dependency initialized.

• rolldown#9998 — P2 A manual codeSplitting group unions modules from disjoint entry-reachability sets into one eagerly-executed chunk, so wi…
• rolldown#9039 — P2 Certain export syntax breaks strictExecutionOrder under code splitting, producing a vendor chunk that runs before its de…
• vitejs/vite#5142 — Dep-optimizer code-splitting emits a common side-effect dependency (e.g. polymer boot.js defining JSCompiler_renamePrope…

correctness/circular-import (1)

Splitting creates an inter-chunk cycle; a binding/runtime-helper is read in TDZ / before its chunk ran.

• rolldown#7449 — P2 CJS + advancedChunks splitting forces a module into a separate chunk, creating a circular cross-chunk import where a con…

correctness/cross-chunk-init-binding (5)

A cross-chunk import/init binding is mis-wired, missing, or aliased wrong → value/helper undefined or wrong at runtime.

• rolldown#9993 — P1 Regression: the __commonJSMin/__commonJS runtime helper is hoisted into the entry chunk and re-imported by code-split CJ…
• rolldown#9887 — P2 advancedChunks + a CJS require + includeDependenciesRecursively:false places a cross-chunk import cycle so a wrapped-ESM…
• vitejs/vite#21952 — P2 With advancedChunks splitting node_modules into a 'vendor' chunk, leaflet's global L binding is undefined at runtime (…
• vitejs/vite#22756 — experimental.bundledDev: Rolldown's __reExport (export-* helper) is referenced in the served dev bundle but never emitte…
• vitejs/vite#22583 — Vite 8 / Rolldown multi-entry Vue build emits calls to init_*_esm_bundler helpers that are never defined or imported acr…

correctness/other (4)

Chunking-caused correctness bugs outside the cross-chunk-init families (filenames, missing facade, getter clash).

• rolldown#8761 — P2 With preserveModules and object-form entry, sanitizeFileName (and custom override) is ignored for emitted JS chunk filen…
• rolldown#5449 — P2 With inlineDynamicImports:true, collapsing all dynamic imports into one chunk causes a runtime TypeError (Cannot set pro…
• rolldown#9209 — P3 In unbundle/preserveModules mode the reachable subpath facade module (card/index.mjs) is not emitted, so the package's s…
• vitejs/vite#22740 — P3 chunkImportMap with multiple entries: shared CSS chunk gets a .js import-map entry pointing at a non-existent file, so t…

quantity/too-many-chunks (4)

Rolldown emits more chunks than needed / than Rollup, inflating request count + size.

• rolldown#4788 — P2 Rolldown does not merge side-effect-free shared chunks across multiple entries (as Rollup's experimentalMinChunkSize doe…
• rolldown#4246 — P2 Small modules (e.g. literal-only) shared across entries are kept as separate chunks instead of being duplicated/inlined,…
• rolldown#8116 — P3 Top-level-await entry plus a shared module is split into 4 chunks where Rollup produces only 3, so the splitting is sub-…
• rolldown#7473 — Default code-splitting produces thousands of tiny chunks (575 on one app) and advancedChunks attempts either break bundl…

quality/facade-empty-redundant-chunk (7)

An extra facade / empty / redundant re-export chunk Rollup would merge away.

• rolldown#9963 — P2 A common chunk that is executed by the entrypoint is no longer merged into the entrypoint, emitting 5 chunks where 4 are…
• rolldown#6677 — P2 With advancedChunks, a pure re-export common chunk becomes empty yet is still emitted and imported because its re-export…
• rolldown#9729 — P3 Manual grouping merges dynamic-import targets into a shared chunk but keeps one extra proxy/facade chunk per original ta…
• rolldown#8935 — P3 Rolldown emits two extra re-export facade chunks (3 total) where Rollup produces 2, since a re-export-only entry is not …
• rolldown#8501 — P3 With dts enabled, a plugin's virtual emitFile entry is treated as a second entry so runtime helpers get split into a red…
• rolldown#7281 — P3 A shared-entry chunk redundantly re-imports the entry before its own export * from external, where the import line cou…
• rolldown#3918 — P3 A side-effect-free dynamic import (await import('./hello')) still emits a real chunk, whereas Rollup inlines it as a f…

alignment/vs-rollup-graph (1)

Chunk-graph metadata/shape diverges from Rollup without a runtime break (parity / introspection).

• rolldown#8100 — P3 Modules fully inlined into a chunk are omitted from chunk.moduleIds, diverging from how Rollup reports modules in a chun…

config-api/manual-chunking (3)

Gaps/bugs in advancedChunks / codeSplitting / preserveModules manual control.

• rolldown#6083 — P2 With advancedChunks, a module shared by two manual chunks is merged into one of them (forcing chunk-to-chunk import) ins…
• rolldown#9603 — P3 Request to expose the post-tree-shake (included) dependency graph to advancedChunks/codeSplitting group callbacks so man…
• rolldown#7116 — P3 advancedChunks maxSize splits purely by file size, scattering related modules across chunks so many/all chunks get loade…

feature/enhancement (10)

Requested chunking capabilities, tracking tasks, and experimental-flag fate decisions.

• rolldown#6427 — P3 Feature request: surface why module execution order changed in the output. The reorder is a direct consequence of chunk …
• rolldown#4697 — P3 Request to apply preserveModules selectively (e.g. src but not node_modules) instead of all-or-nothing chunk emission.
• rolldown#2654 — P3 Request to inline rolldown:runtime helpers into each chunk instead of sharing one runtime chunk, to stop runtime chang…
• rolldown#9703 — Request a plugin hint to mark a module as inline-only so preserveModules folds it into importers instead of emitting a c…
• rolldown#9559 — Tracking task to decide whether to stabilize, keep as a debug toggle, or remove experimental.chunkOptimization once chun…
• rolldown#9558 — Tracking task to decide the fate of experimental.chunkModulesOrder, the in-chunk module rendering order that swung total…
• rolldown#9557 — Tracking task to decide the path to stable for experimental.chunkImportMap, blocked on validating the Vite 8.1 beta inte…
• rolldown#7309 — Documentation request for recommended advancedChunks recipes (vendor/shared presets) so users have a sane starting point…
• rolldown#7114 — Tracking issue for next steps on manual code splitting (webpack-style splitChunks, rename maxSize, eliminate barrel chun…
• rolldown#4437 — Tracking issue for controlling output chunking across default, preserveModules, and single-file (no-shared-chunk) modes,…