The edit log

The edit log is the only state of an editing session. It is a JSON document: the source descriptor, the plugin versions that wrote it, optional assets, and an append-only list of operations.

json

{
  "version": 1,
  "source": { "id": "IMG_0042", "width": 6000, "height": 4000, "hash": "9f3e…" },
  "plugins": { "crop": 1, "finetune": 1, "filter": 1 },
  "ops": [
    { "type": "finetune.set", "id": "01J…", "params": { "brightness": 0.1 } },
    { "type": "crop.set", "id": "01K…", "rotation": 0.0872, "rect": { "x": 0.1, "y": 0.1, "width": 0.8, "height": 0.8 } }
  ]
}

A pure reducer folds ops[0..index) into a document (what the UI binds to) and a render plan (what the core executes). Undo, redo and time travel are prefix slices; nothing is ever re-encoded.

Every op is validated at runtime with the plugin's schema. Unknown plugins are rejected. Old logs migrate through migrate(fromVersion, op). The parsed log then records the current plugin versions, so a second parse migrates nothing.

Ops carry an id and an optional at. Neither affects pixels: the renderer ignores them, so a log that differs only in ids and timestamps renders the same bytes.

The edit log ​

The edit log