Implementations

Project NameLanguage BindingsOperating SystemApp Lifecycle TypeEnvironment Data source
glean-coreRustallallnone
gleanRustWindows/Mac/LinuxDesktop applicationOS info build-time autodetected, app info passed in
Glean AndroidKotlin, JavaAndroidMobile appAutodetected from the Android environment
Glean iOSSwiftiOSMobile appAutodetected from the iOS environment
Glean.pyPythonWindows/Mac/LinuxallAutodetected at runtime
FOG1Rust/C++/JavaScriptas Firefox supportsDesktop applicationOS info build-time autodetected, app info passed in

Features matrix

Feature/BindingsKotlinSwiftPythonRust
Core metric types
Metrics Testing API
baseline ping23
metrics4
events5
deletion-request ping
Custom pings
Custom pings testing API
Debug Ping View support

1

Firefox on Glean (FOG) is the name of the layer that integrates the Glean SDK into Firefox Desktop. It uses the Glean Rust bindings and exposes the same Rust API inside Firefox and extends it with a C++ and JavaScript API.

2

Not sent automatically. Use the handle_client_active and handle_client_inactive API.

3

Sent automatically on startup if necessary. For active/inactive pings use the handle_client_active and handle_client_inactive API.

4

Needs to be enabled using use_core_mps in the Configuration.

5

Sent on startup when pending events are stored and when reaching the limit. Additionally sent when handle_client_inactive is called.