devenv vs FVM

devenv uses Nix to define development environments for teams and CI. A project configuration can specify packages, languages, services, tasks, secrets, variables, files, and shell scripts. The project lists 58 supported languages and 42 preconfigured services, including PostgreSQL, Redis, MySQL, RabbitMQ, and Elasticsearch. Processes can be supervised with dependencies and restarts, while tasks can run in parallel and integrate with shells or commits. SecretSpec can read declared secrets from sources such as Keychain, 1Password, LastPass, dotenv, and environment variables. devenv can build OCI containers and run integration tests with its processes active; documentation also describes GitHub Actions use for checks, builds, and tests. It requires Nix and works on Linux, macOS, and WSL. As of devenv 2.4, the project no longer builds, tests, or releases it for Intel Macs. Projects must be explicitly trusted before automatic activation. The software is free and MIT licensed, with GitHub and Discord linked for help and community. Cached shell startup is listed as under 100 ms after the first build; devenv Cloud is in private beta.

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.