@startuml !pragma useVerticalIf on actor ユーザー as user participant "フロントエンド" as frontend participant "バックエンド" as backend participant "データベース" as database user -> frontend: ツイートを送信 activate frontend frontend -> backend: ツイートを送信(ユーザーID, テキスト) activate backend backend -> database: ツイートを保存(ユーザーID, テキスト) activate database database --> backend: 保存成功 deactivate database backend --> frontend: 保存成功 deactivate backend frontend --> user: ツイートの表示更新 deactivate frontend @enduml Submit amiga aws-orange black-knight bluegray blueprint cerulean-outline cerulean crt-amber crt-green cyborg-outline cyborg hacker lightgray mars materia-outline materia metal mimeograph minty plain reddress-darkblue reddress-darkgreen reddress-darkorange reddress-darkred reddress-lightblue reddress-lightgreen reddress-lightorange reddress-lightred sandstone silver sketchy-outline sketchy spacelab spacelab-white superhero-outline superhero toy united vibrant       Pure Javascript  PNG  SVG  ASCII Art