- An image a layer or style still shows can't be removed: removing it and
putting other bytes under its key would swap the picture that layer
shows, which giving the key other bytes directly can't. A batch made by
the diff stops using an image (node changes, then styles) before it
removes it; an undo keeps the changes that apply, so its image may stay.
- Restore and replay leave out the image entries history written under
older rules can't apply, using one method shared with the undo history
(Replica::apply_kept, extracted from history.rs). It is exact for every
image rule, including removals in use and replacements, and leaves out
only image entries: any other change that doesn't apply is still an
error. The image-only filter it replaces is gone.
- A server whose restore or replay left image entries out, or whose saved
log puts images, catches every resuming client up with its snapshot,
including one at the same sequence number.
- Tests: an_image_in_use_cannot_be_removed,
an_image_no_longer_in_use_can_be_removed, undoing_an_image_layer_still_works,
a_restart_replays_past_a_logged_removal_of_an_image_in_use,
a_resume_after_history_was_left_out_catches_up_with_the_snapshot,
a_resume_after_a_clean_restart_catches_up_with_the_log,
a_snapshot_with_a_broken_layer_change_still_fails_to_open.
- Docs: collab-protocol.md, collaboration-parity.md.
- without_refused_images judges each image entry against the document it
applies to and the batch's earlier entries (image_for, shared with
apply): a logged put of other bytes under a key the replay state holds
is left out, so a restart no longer stops there and drops the rest of
the log.
- Server::restore keeps its saved log only when the log puts no images:
a resuming client may already hold other bytes under a logged key, which
the restored state can't check, so clients catch up with the checked
snapshot instead.
- Tests: a_restart_replays_past_a_logged_image_replacement,
a_client_resuming_past_a_refused_image_in_the_saved_log_catches_up,
a_client_resuming_past_a_replaced_image_in_the_saved_log_catches_up.
- Docs: collab-protocol.md, collaboration-parity.md.
- The entry size cap is figcraft_doc::ImageData::MAX_BYTES (256 MiB), the
cap the .fig, .sketch and REST importers already read images with (now
one constant), instead of 32 MiB: an imported image larger than 32 MiB
made the document unjoinable and its server snapshot unrestorable.
- History written before the checks (a restored or joined snapshot, a
replayed server log, a file published to a server) applies without the
image entries they refuse (docprops::without_refused_images), instead of
the file not opening or a restart dropping every edit after the image.
- A key that already holds an image can't be given other bytes: producers
key images by their bytes (the REST importer's placeholder keys always
hold the same picture), and merge treats a key's image as never
changing.
- REST import: an unresolved imageRef shaped like a content hash shares
the rest-image-missing placeholder (the placeholder's bytes don't hash to
it); ImageData::claims_content_hash is shared with collab.
- Tests: collab image_tests (4 new, size test uses a small cap), format
image_tests (1 new).
- Docs: collab-protocol.md, collaboration-parity.md, file-format-parity.md.
The Share popover is one flow: Online (the file is published to the server in
Preferences and the server names its links with short codes) or Local network
(the app hosts; the code carries its address and the session's secret), one
Start sharing button, the code large with Copy code and Copy link, who is here,
can edit / can view, and Stop sharing. Join with a code is one field in the
popover, on the home screen and in the Join dialog, for a code of either kind
or an invite link.
Protocol (within version 2, new variants last): Resolve / Resolved and Admin
code. The server keeps a stretched hash and the wrapped token, never the code,
and limits wrong codes per address (with a lockout) and for everyone. Older
servers leave the links in place of a code; older apps join by link.
collab.share, collab.join {code}, code and share in collab.peers; the server
preference defaults to the built-in server and can be reset or turned off.
Fixes from the security review of the public server:
- team libraries only in key-published files on open servers; unpacking
bounded by the file cap (zip bombs refused)
- byte-bounded send queues per connection and in all, a bound on bytes
waiting for the hub, per-address and global download budgets
- batches checked against the file, per-address and total caps as files
grow (refused with a Reject the app rolls back); the core's recent-batch
memory bounded in bytes; nothing confirmed when a log can't be written
- usage reports kept in memory; per-kind message caps checked while read
- layered IPv6 limits (/64, /56, /48), a global publish rate, connections
reserved for sessions, short idle timeout for one-shot requests
- revoked links and removed files cut library connections
- data directory 0700, server key 0600 from creation
- install.sh: SSH ports from sshd, ufw left off when other services
listen, unprivileged builds of the latest tag, settings checked before
use, own Caddy snippet; systemd memory and network caps; backups check
free space and say they hold the key
- linger reads raw bytes after an oversized frame (tungstenite asserted)
Config-gated (open_publish): anyone publishes without the server key and
gets an owner token (128-bit, shown once, stored hashed) that manages only
that file. Per-address limits (X-Forwarded-For only from trusted_proxy,
bounded tables), global caps, idle expiry, reports, persisted blocks,
files list --sort, check, GET /healthz on the same listener, startup
warnings. The app asks the server first, publishes without a key when it
is open, shows the owner token once, the host/terms line, the expiry date
and a report button; collab.serverInfo, collab.manageFile, collab.report
and pref.publishServer for MCP/CLI. Protocol additions stay within
version 2, gated like signals.
A self-hosted plugin directory, with no third-party service: `figcraft-server` keeps plugin bundles,
the app browses, installs and updates from it, and `figcraft-cli` publishes to it.
- **Bundles** (`figcraft_plugin::bundle`): a plugin's manifest, module and up to 32 plain-named
assets in one uncompressed, length-prefixed binary form (nothing can expand beyond the bytes
sent). Its SHA-256 names it. `Bundle::decode` never allocates beyond its input and refuses
trailing bytes; `Bundle::check` parses the manifest (refusing a plugin API this build doesn't
run), requires a version of 1-4 numbers, compiles the module without running it (only the
sandbox's imports allowed) and checks asset names (no paths, no dot files, no Windows device
names, unique ignoring case). Manifests gain an optional `author`.
- **Protocol**: a new connection kind next to managing and team-library connections:
`OpenPlugins {key}` then `Plugins {list | fetch | publish | unpublish}`. Browsing needs no
credential; publishing and unpublishing need the server key (a wrong key is refused). Older
servers refuse the connection and the app says the server has no plugin directory. The protocol
version is unchanged; old clients are unaffected.
- **Server** (`apps/figcraft-server/src/directory.rs`): `<data>/plugins/index.json` plus
`<data>/plugins/<sha256>.bin`, so no publisher-chosen name reaches the file system. Every publish
is checked in full and must be a newer version; caps `max_plugins` (versions, 0 turns it off),
`max_plugin_mb` (<= 32), `max_plugins_mb`. Fetches re-hash the file before sending (a damaged
bundle is never sent) and share a download budget (~32 MiB/s) so a flood is refused, not queued.
Damaged index entries are skipped and reported, never deleted; an unreadable index lists nothing
and refuses writes until the operator fixes it. Operator moderation:
`figcraft-server plugins [list]` and `plugins remove ID [--version V]` (offline or through the
running server). Logs name ids and versions, never keys.
- **App**: Plugins > Manage plugins gets Installed / Browse tabs. Browse lists a server's plugins
(version, author as typed, size, access) with a search; nothing is fetched until Browse is
pressed. Install / Update open a confirmation listing the permissions asked for, the source and
the SHA-256; only its button downloads. The download must match the listed SHA-256 (and the one
shown), then is checked like an imported plugin before anything is written. Installed plugins
live per user under `<settings>/FigCraft/Plugins/<hash of id>/` and run in the same sandbox;
Remove deletes the folder.
- **Commands**: `plugin.directory.list {server?, query?}`, `plugin.directory.install {id, version?,
confirm, server?, sha256?}` (refused without `confirm: true`; never opens a dialog),
`plugin.directory.publish {path | plugin, server}`, `plugin.directory.unpublish {id, version?,
server}`. `ui.set {pluginsTab, pluginConfirm}` on the control channel.
- **CLI**: `figcraft-cli plugin publish FOLDER --server ws://host:port/` with the key from
`FIGCRAFT_SERVER_KEY` (or `?key=`), never printed.
- Docs: plugins.md (directories, publishing, commands, manifest), server.md (operating the
directory: access, checks, caps, moderation, backups, security), collab-protocol.md, mcp.md,
cli.md, control-protocol.md, target-app-parity area 18 and Ecosystem, ROADMAP, roadmap.md M11,
gaps.md gap 6. Plugins & widgets 55%/32% -> 60%/35%, 10-30 h -> 8-26 h.
Two presence features for live sessions, with no accounts needed:
- **Cursor chat.** In a live session, `/` on the canvas opens a bubble in your colour at your pointer. What you type goes to everyone as you type, and others see it next to your cursor in place of your name tag. Enter (or clicking away) sends it and closes the box. On every screen it fades a few seconds after its last change (5 s, then a 1 s fade; with reduced motion it vanishes without fading). Escape takes it back at once and doesn't deselect. A box left open without typing closes by itself. Limits: 100 characters, control characters become spaces. Agents use `collab.cursorChat {text}`.
- **Spotlight.** Your avatar (top of the right panel) now has a menu with Spotlight me / Stop spotlighting (`collab.spotlight {on?}`). Everyone else follows your view and page, using the existing follow. People who join later are told by the server and follow too. Anyone who pans, zooms or presses Escape stops following, and a canvas banner ("Hana is spotlighting", Follow) lets them follow again. A newer spotlight takes over the old one. The presenter leaving or stopping ends it. The presenter sees a banner with Stop. After a reconnect, your spotlight goes out again.
- **Protocol: signals.** New `ClientMsg::Signal {kind, text}` and `ServerMsg::Signal {client_id, signal}` carry ephemeral presence. Signals never go into the document, the log or a saved state; the server keeps only who is spotlighting, for newcomers. The server cleans each signal: unknown kinds, malformed spotlights, a client's `ready` and anything over 1 KiB are dropped, and chat is capped and has control characters replaced. The app checks what arrives again before showing it. The hub rate-limits signals per connection (20 a second, bursts of 40) and drops the excess without closing the connection.
- **Compatibility, both directions.** A client that reads signals announces it with the word `signals` in its hello's `client_version`, and the server sends signals only to those clients, so older clients never see a message they can't decode. A server that takes signals answers with a `ready` signal after the welcome, and the client sends signals only after that, so older servers never get one; the app says the host runs an older version. Signals are kind plus text, so clients skip kinds added later and servers drop them.
- Engine: `Live` keeps `signals`, `chats`, `chat`, `spotlight` and `spotlighting`, all reported by `collab.peers`. UI: chat bubbles, the chat box, the spotlight banner (the existing canvas banner widget), the avatar menu and `ui.inspect` fields. Keymap: `/` maps to `collab.cursorChat` (Essential). Spanish labels for both commands, plus en/es UI strings.
- Docs: collab-protocol (messages, compatibility, Presence, security limits, agents), mcp.md, collaboration-parity rows, target-app-parity, ROADMAP, gaps, ui-parity.
A file's library can be published to figcraft-server and enabled in other files by a share link (view access is enough); placing, styles, variables and library updates with overrides kept work as for local libraries, with a background check while the Assets panel is open. library.swap re-points instances, styles and variables to another library by name (one undo step, unmatched items listed). The server keeps per-file usage reports (library.usage).
figcraft-server hosts many files over the same hub the app uses for sessions, persists each as a checksummed snapshot plus an append-only log (synced before replies, compacted, damaged files skipped and reported) so restarts lose nothing confirmed, and gives per-file share links with edit or view access (hashed 128-bit tokens, revocable). The app can publish a file to a server and join server-hosted files; view-only tabs refuse edits. Protocol version 2.
- Styles, variables, collections, modes and comment threads created in a live
session take ids from the creator's client space (figcraft_doc::ids: a
number from the node id allocator, client_id << 32 | counter); outside a
session ids are made exactly as before. The server refuses a new entry in
another connected client's space (removed entries can be put back by undo),
keeps removed entries in its saved state, and starts client ids above every
space used by any kind of id.
- Others' text carets and selected characters show on the canvas in their
colour at the glyph positions, with their name above the caret (no blinking,
no frames of their own). Typing in a layer someone else is typing in says so
(toast and tag); collab.peers reports who types where.
- Toasts wrap at a readable width.
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
* M9: collaboration: per-user undo, rejections, reconnect
Step 3 of docs/collab-protocol.md, the parts that don't need the transport:
- Per-user undo and redo (figcraft_collab::Client::{undo, redo}): each undoable batch is a step
(values before/after by target, nodes created/deleted). Others' batches ordered after the step
take its targets for good; creates invert to deletes (not when others built inside), deletes
re-create the subtree. An undo or redo waits for every earlier batch and is remade from the
confirmed state when it goes out; derived data follows as a follow-up batch.
- Rejections: refused batches leave the history (with an undo waiting on them) and queue a
Notice; the engine shows it through Session::message (the UI's toast).
- Offline queue and reconnect: Hello.resume {session, client_id, seq}; the server keeps a
bounded log and answers with the missed batches or a snapshot, plus what it did with the
client's batches (processed {last_batch, refused}); queued batches then go out.
Server::state / restore persist the session (client-id counter, log, session id).
- Presence carries editing_text {node, caret, selection}.
- Engine: documents in a live session (LiveDoc, Session::collab_*): commands, gestures and
groups sync as one step each; edit.undo / edit.redo route to the per-user history; remote
edits show under a gesture in progress. Outside a session snapshot undo is unchanged.
- Sim: dropped connections, undo/redo, and a checker that no undo reverts a change by someone
else its author had seen. New tests in undo_tests, reconnect_tests, collab_live_tests,
collab_undo_tests.
- CLAUDE.md / AGENTS.md: collab in the L2 layer list.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* M9: collaboration wording in the progress docs after per-user undo and reconnect
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* M9: protocol doc: what the engine's live-session tests cover
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
* M9: real-time collaboration protocol (design)
docs/collab-protocol.md: WebSocket sessions with a server-ordered,
per-property last-writer-wins document sync, client-scoped ids,
fractional positions for children, ephemeral presence (cursors,
selections, follow), per-user undo, hosting from the app first and a
self-hosted server next, and the implementation plan. ROADMAP gains M9.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* M9: collaboration core: ids, change sets, server ordering, convergence
Step 1 of docs/collab-protocol.md, no networking:
- Client-scoped node ids: Document::set_client_id makes alloc_id hand out
client << 32 | counter; single-user files allocate as before; the id
counter is no longer part of document equality.
- crates/collab (layer 2): the synced object/property model (every saved
Node field, plus document-level styles, comments, variables, images,
dev snapshots, library data), Change batches, an O(changed) diff, strict
and lenient apply, fractional sibling positions, snapshots.
- Server (ordering, validation, rejects with fixes) and Client (optimistic
view, replay under remote batches, author-side repair of derived data)
as pure state machines; binary (version byte + postcard, JSON values) and
JSON message forms, fuzzed decoders.
- Engine: normalize as the recompute hook, collab.diff.
- Tests: round trips over random real commands, an N-client convergence
fuzz test over delayed in-order links, junk batches.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
* M9: fmt after merge
---------
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Christopher Linnett