FVM vs Jabba

FVM manages Flutter SDK versions by project, allowing teams to keep builds consistent while using different versions across projects. A project’s `.fvmrc` file records its selected Flutter version and can include project-specific settings and flavors. FVM switches among installed SDKs without downloading them again. It can identify unreferenced versions, preview cleanup candidates, and remove unused SDKs with `fvm cleanup`. The documentation describes commands suitable for CI/CD automation and support for custom Flutter repositories. FVM provides packages for macOS, Linux, and Windows, with architecture availability varying by system. Installation options include a shell script, Homebrew, Chocolatey, Pub, and standalone packages. FVM detects VS Code and updates `.vscode/settings.json` for the Dart Code extension to use the project’s managed SDK. Android Studio and IntelliJ settings must be configured separately to point to the FVM SDK path. JSON API commands expose installed SDKs, releases, cleanup data, environment context, and project configuration. FVM stores known project roots in a machine-local file and says it does not scan disks for projects. The project is licensed under MIT.

Jabba is a free Java version manager written in Go for installing and switching among JDK versions on macOS, Linux and Windows. Its JDK index, powered by DiscoAPI, lists versions for the user's operating system and architecture. The README names distributions including Oracle, Adopt OpenJDK, Zulu, IBM SDK, GraalVM, OpenJDK, Liberica and Amazon Corretto. Users can list remote JDKs, filter versions with semantic version ranges, install versions and switch among those installed. A `.jabbarc` file can specify a project's JDK, while a default alias can select the version used in new terminals. Jabba can link to a system JDK and coexist with an existing Java installation. The README documents shell integration for bash, zsh and fish, plus installation through Homebrew, shell scripts, PowerShell, Scoop or Docker. Custom JDK downloads are also supported. Jabba does not switch Java globally on its own; the README gives manual platform-specific snippets instead. The repository describes Jabba as a community fork that is a work in progress and warns that some README instructions may be outdated. It is licensed under Apache-2.0.