Install Custom Application in Jira

we have our own developed a PHP application in .zip format. Can you let us know how to install such applications in Jira ?

Cloud or Server? For Server - you can’t (p2 apps have to be created as Atlassian sdk apps - maven/java etc).

For Cloud - you’ll need to host the app and follow the Atlassian Connect framework guidelines: https://developer.atlassian.com/cloud/jira/platform/integrating-with-jira-cloud/

I think it might be possible (there were some php in java implementations), but might be a PITA to integrate that into p2.

Our is server installation

Is there a guide available how to develop custom application in Jira ?