Cheap LFS Bambu build cloud, clone, and batching acceptance — 2026-07-23

This receipt records a live public-repository Cheap LFS acceptance with a real 14.8 GB Windows build tree. The four app-created payload batches, managed cloud caller, one-object-at-a-time compression, exact manifest verifier, immutable verification release, and initial fresh UI-clone integrity proof completed on the logged-in codingmachineedge Desktop Material account. The run used the fixed Lowlevel MCP server on an isolated off-screen Win32 desktop; no visible-desktop interaction or credential copying was used.

One UI-concurrency result remains deliberately open. The first explicit Materialize-all action overlapped clone/open automatic materialization and created two exact compare-and-swap recovery duplicates. All ten resulting working files still matched their expected hashes, but a corrected build with repository-scoped serialization must repeat that UI action before the final screenshot is promoted. This receipt does not turn that pending rerun into a success claim.

Repositories and inventory

• Source: clean Ding-Ding-Projects/BambuStudio commit 0c08db803478647e79895dac20a9db12d5719b94.
• Public destination: codingmachineedge/bambu-build.
• Copied payload: exactly 8,305 files and 14,809,588,162 bytes from the complete build folder, including the materialized src/Release/resources junction.
• Preserved destination content: the repository's original README.md.
• Cheap LFS set: exactly ten files strictly above 100 MiB, totaling 9,428,683,391 bytes. Every copied file matched its source SHA-256 before the app replaced it with a pointer.
• Storage release: prerelease tag bambu-build-20260723-1105-41718cda, with 13 retained raw assets. Three logical objects are split into two parts below the 1.5 GiB ceiling.

The ten pointer paths, logical sizes, source digests, and committed pointer-blob sizes at 712ad85f92f9002474f0f13b6bb6991153d586af are:

UI commit and batch-push proof

The installed app prepared all ten pointers and created four ordered commits through the real Changes UI. Each used the bilingual subject Add Bambu build / 加入 Bambu build and a bilingual body.

The first attempt used Git's normal packing and received HTTP 408 after 675.591 seconds. The exact pending commit remained durable and retryable, then the same immutable SHA succeeded with pack.window=0 and pack.compression=0 scoped to that exact push process. The following three batches used the same process-local fast-pack path. Normal pushes and persistent Git configuration remain unchanged.

For every batch, the run proved commit creation, exact-SHA fast-forward push, remote-tip equality, and durable pending-ref cleanup before the next commit. Local and remote main ended equal at f58fd4c026ba813fd01b2fe774835553d16a9044 before the cloud caller was added.

Cloud compression, manifest, and remote verification

The real UI added the managed public caller in bilingual commit fc1bedb2f98302e585a37e396fb411c34d16a594 only after the payload batches were remotely proved. Cloud run 30048474438 then processed each of the 13 raw Release objects independently. It compressed 13, kept 0 raw, and failed 0. Thirteen pointer-only bot commits ended at ce438aa4c1f87b55a152f632bffab4a0732792b9.

The storage release retained all 13 raw originals (9,428,683,391 bytes) and added 13 verified compressed assets (1,491,654,444 bytes), for 26 assets total. Keeping the originals preserves raw fallback for historical pointer commits even after current pointers adopt compressed parts.

The first verifier run 30048474451 failed as expected because no authoritative build manifest had been committed; it did not report a payload-integrity mismatch. The real Changes UI then committed and pushed exactly the manifest and managed-workflow action pin in 712ad85f92f9002474f0f13b6bb6991153d586af.

Verifier run 30054805137 passed the exact 8,305-file inventory, ten pointers, and 26 Release assets. Its immutable release bambu-build-verify-30054805137 points to exact commit 712ad85f92f9002474f0f13b6bb6991153d586af and contains one bambu-build-manifest.json asset: 5,489 bytes, SHA-256 234e88a446073d59c293e40966b6cbcfa080e21467fe14df840452d0c04694b3. The paired final cloud run 30054805097 completed as a clean no-op with 0 compressed, 0 kept raw, and 0 failed safely.

Fresh UI clone and serialization follow-up

Desktop Material cloned the public repository through the real Clone UI to a new owned directory. Local HEAD was exact 712ad85f92f9002474f0f13b6bb6991153d586af. All ten materialized working files matched the manifest SHA-256 values (10/10), while git cat-file proved that the committed objects remained the small pointer blobs shown in the table. This establishes remote restore integrity for the compressed objects and their locally decompressed output.

The same run exposed a UI scheduling race: clone/open automatic materialization was still active when Materialize all began. Two paths reached the exact compare-and-swap recovery-duplicate fence. The hashes ultimately remained correct, but that overlap is not accepted as final concurrency behavior. A repository-scoped serialization fix followed. Its deterministic real-Git and UI routing regressions pass, and the linked run manifest records the inspected live ten-pointer frame separately from this fresh-clone byte proof.

Safety and cleanup

• The three unrelated pre-existing ambiguous assets draft releases were not renamed, published, or deleted.
• The logged-in app credential was used in place; it was never printed or copied.
• The independent BambuStudio linked worktree and its untracked files were preserved.
• No force push or history rewrite was used.

The detailed headless run parameters, serialization regression receipt, and intermediate evidence are retained in 2026-07-23-bambu-build-cheap-lfs-live.md.