Questions. And Answers.

What platforms and languages are supported? BugJail is currently available only for JVM (all versions from 1.6 through to 13). Currently, the source-level debugging feature works only with Java, while all other features should work with any JVM language. Next is BugJail for Android, with beta testing starting mid-2020. After that either JavaScript/TypeScript, .NET, Swift/iOS or Python.

What is the performance impact of BugJail? Program startup slows down by a fixed ~0.5 sec when BugJail's capturing agent is initialized, and then the rest of the program startup time has a proportional overhead of around 60-90% when the capturing agent instruments classes while they are being loaded. Program execution itself doesn't usually slow down noticeably (~5%) if you have typical IO-bound web, enterprise or business application. BugJail is also fast enough to capture from CPU-bound programs, such as AI algorithms and compilers. For CPU-bound programs, the performance impact is typically in 100-300% range - significant but still certainly usable.

Does BugJail send my source code to the Cloud? No. BugJail is a desktop application. Nothing about your project, source code or bytecode is sent to the Cloud.

Is there any risk to my production environment? No. BugJail is purely development time tool. It simply doesn't touch the production environment in any way.

Can I use BugJail in pre-production or production environment if I really, really want? No. BugJail just isn't currently suitable for this, and use elsewhere other than developer's workstation is explicitly prohibited both by the license terms and by technical restrictions (the capturing agent can only connect to localhost). We are steadily working on making BugJail suitable for pre-production and production use, but this will be a separate edition with different licensing, and it's likely to be several years away.

Do I need to modify source code? No. To capture program execution to BugJail, the only thing you need to do is start the Java Virtual Machine with one additional option.