--- title: Pending Synchronization status: draft maturity: hypothesis families: [synchronization] scales: [L2, L6] admission: research-candidate-only --- # Pending Synchronization Context: edits persist while connectivity is absent or intermittent. Problem: local success does not establish a remote receipt. `offline-usability` competes with `freshness`; retries add `reconciliation-complexity`. Proposed solution: retain stable revision/operation identity and pending work across restart, retry on reconnection, and distinguish queued, sent and acknowledged states. A sent request alone never means synchronized. Define deduplication and the acknowledgement scope at the receiver before retrying. Do not infer that every other device has seen it. Result: progress can resume after interruption without relying on volatile UI state. A lost response leaves the same operation pending; an idempotent retry or lookup must resolve uncertainty. Infinite retries, expired authorization and sync-disabled items need explicit observable states rather than a permanent spinner. Evidence: [expansion review](../reviews/LocalFirstEvidenceExpansion.md) E05/E06 documents Joplin's distinct sync process and per-item progress metadata. The precise retry protocol here is a hypothesis, not a verified implementation description. Known uses of the full contract and recurrence: unknown. Alternative: server-required writes, which sacrifice offline operation; untracked best-effort upload, which lacks restart recovery. Proposed connections: [Local Commit Boundary](LocalCommitBoundary.md) provides a persistent origin; detected divergence may create context for [Conflict Copy](ConflictCopy.md). Neither relation implies every sync needs a conflict copy. See the VC-02 walkthrough.