New Diagram
A new diagram gets its own secret link. Send the link to the people you want to work with — everyone who opens it edits the same diagram at the same time, and sees the others' cursors.
Diagrams are stored on this server in plain text. Anyone who has the link can read and change the diagram, so treat the link like the content. A diagram nobody opened for 180 days is deleted.
Recently Opened
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Join to edit togetherSource
Diagram
Drag from one lifeline to another to add a message (hold Shift for a dashed reply, Ctrl for an open arrow). Double-click anything to edit its text, drag messages, notes and fragments (by their label) up or down, drag participants sideways, right-click for notes, dividers and fragments, select and press Delete to remove. Drag with the middle mouse button to move the view.
Syntax reference
Participants
title My Diagram participant Alice actor User database DB #lightblue participant "Auth\nServer" as Auth boundary B control C entity E collections Many queue Q
Participants used in a message appear on their own. Declare them to fix the order.
Messages
A->B:sync call B-->A:reply A->>B:async A-->>B:async reply A<->B:both ways A-xB:lost A->A:self A->*C:create C [->A:from outside A->]:to outside A-[#red;2]>B:styled
Notes & boxes
note over A:text note over A,B:spans both note left of A:text note right of A #yellow:text box over A:plain box abox right of A:angular rbox over A:rounded ref over A,B:other diagram
Fragments
alt success A->B:ok else failure A->B:error end loop every second A->B:ping end opt / par / break / critical group custom name [condition] ... end
Lifelines
activate B deactivate B deactivateafter B autoactivation on create C destroy C destroyafter C destroysilent C participantgroup #lightgreen Backend participant API participant DB end
Layout & text
autonumber autonumber off ==divider== space space 3 frame Overview bottomparticipants // a comment **bold** //italic// ""mono"" ~~strike~~ line one\nline two
The syntax follows sequencediagram.org closely. Lines this tool does not understand are marked in the
source and skipped in the drawing; styling commands such as participantspacing or
fontfamily are accepted and ignored.
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