Two Artifacts
.postsnail is the private editable Shell. .zip is the public signed Website artifact. Importing the Shell restores the real project; public ZIP recovery can only recover public content.
Stable Core
Protocol records use protocol postsnail and version 1. The required core features are signed-manifest and file-hashes.
Optional Extensions
Unknown optional features and extension data are ignored safely. Current optional features include identity documents, commit history, sitemap, workspace vaults, tracker announce, Forest tracker, ShellNames, Site Moves, comments, deployment assistants, and plugins.
Required Features
Unknown required features fail clearly. A feature should become required only when ignoring it would make verification unsafe or misleading.
Legacy Exports
Old valid exports may miss feature declarations or optional files. PostSnail verifies them when signatures, hashes, and required proof data are valid, then shows legacy warnings.
Workspace Migrations
Old workspaces migrate step by step. Future unsupported versions fail with This workspace was created by a newer PostSnail version.