File System
A file system is the durable, versioned store — one shared timeline. Autosave checkpoints are kept as a recent recovery window; permanent snapshots are kept until you delete them (see Retention).- CLI
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Mount
A mount gives a sandbox a directory backed by a file system.- CLI
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/work like any other directory while the sandbox is running. Reads stream in lazily, so mounting is fast regardless of how much the file system holds.
Session
A session is the state behind one writable mount. It records which checkpoint the mount started from and owns a crash-safe local journal for changes that have not reached the server yet. Sessions survive unmounts and sandbox crashes. Remounting a file system this machine has a detached session for resumes that session:- CLI
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tl fs ls agent-scratch lists a file system’s sessions.
Autosave Checkpoint
An autosave checkpoint is a durable, shared recovery point for the mounted file state. Writable mounts replicate settled changes through a per-session server WAL automatically, including at a bounded interval when an agent writes continuously. The server verifies and applies each acknowledged checkpoint to the shared file-system timeline before returning success. Following mounts can observe it on their next head poll, typically within seconds of the original writes settling. Automatic points appear underRecent autosave WAL in tl fs history. They are ephemeral: Tensorlake retains the newest 256 and all points from at least the most recent 24 hours, then truncates older entries automatically.
Permanent Snapshot
A snapshot with new changes marks that generation as a permanent, billed retention point:- CLI
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tl fs history, can be restored or mounted read-only, and remain until you run tl fs delete-snapshot.
Retention
Autosave checkpoints are retained as a bounded recent window so long-running mounts do not accumulate history without limit. Permanent snapshots are billed storage, structurally exempt from automatic expiry, and remain until you delete them.Publishing
Writable mounts publish: every acknowledged autosave checkpoint advances the file system’s shared timeline, and other mounts converge to it automatically. The server WAL is the crash-safe commit path, not a private 15-minute staging window.tl fs status shows the mode:
Concurrent Writes
Several mounts can write to one file system at once. Crystallized updates that touch different paths merge automatically. Two mounts publishing the same file in overlapping windows are last-writer-wins — the later ordered update’s version sticks, silently. A file system is a shared drive, not a set of branches, so there are no conflict markers. See Concurrent Writes.Retained Files
After a checkpoint publishes, the mount keeps local copies of its files as a byte cache — reads stay local and future autosaves stay incremental.tl fs status counts them under retained:. They are already durable; the cache only costs local disk.
Credentials
tl login stores a Tensorlake CLI credential. tl fs commands mint and refresh the short-lived credentials they need automatically — including inside sandboxes, where tl fs token <filesystem> mints the scoped credential a guest needs to attach one file system.
You only handle credentials yourself on the Git surface. See Authentication.