Crashlytics Migration Lint for App Center
Finds every leftover Visual Studio App Center SDK call in your mobile code and names the Firebase Crashlytics call that replaces it.
Microsoft retired App Center on 2025-03-31: since then you cannot sign in and API calls fail. Microsoft extended App Center Analytics & Diagnostics until 2026-06-30. After that date, Crashes.TrackError, Analytics.TrackEvent and the rest of the SDK still compile and still run. Nothing breaks the build, so a crash dashboard that went quiet is easy to miss.
Home page and the free web version: https://getreadystack.com/tools/crashlytics-migration-lint
What it checks (18 rules)
| Rule |
Leftover App Center code |
Crashlytics replacement |
| AC_IMPORT |
using Microsoft.AppCenter…, import com.microsoft.appcenter…, import AppCenter, from 'appcenter-crashes' |
Plugin.Firebase.Crashlytics / firebase-crashlytics / FirebaseCrashlytics / @react-native-firebase/crashlytics |
| AC_PACKAGE |
NuGet, Gradle, CocoaPods, SPM and npm references |
the matching Crashlytics package + Gradle plugin |
| AC_START |
AppCenter.Start(…) / AppCenter.start(…) |
FirebaseApp from google-services.json / GoogleService-Info.plist |
| AC_SECRET |
ios=<guid>;android=<guid> app secrets |
delete; Firebase uses its config file |
| AC_TRACK_ERROR |
Crashes.TrackError(ex, props) |
recordException / record(error:) / recordError + setCustomKey |
| AC_TRACK_EVENT |
Analytics.TrackEvent(…) |
Crashlytics log() or Google Analytics logEvent() |
| AC_TEST_CRASH |
Crashes.GenerateTestCrash() |
a thrown exception / fatalError() / crash() |
| AC_USER_ID |
AppCenter.SetUserId |
setUserId |
| AC_ENABLED |
SetEnabledAsync toggles |
setCrashlyticsCollectionEnabled |
| AC_CONSENT |
ShouldAwaitUserConfirmation, NotifyUserConfirmation |
collection off + sendUnsentReports / deleteUnsentReports |
| AC_ATTACH |
GetErrorAttachments, ErrorAttachmentLog |
log() (64kB per session) + custom keys |
| AC_LAST_SESSION |
HasCrashedInLastSessionAsync |
didCrashOnPreviousExecution |
| AC_CALLBACKS |
SendingErrorReport and other send callbacks |
no equivalent; remove |
| AC_DISTRIBUTE |
Distribute.CheckForUpdate and in-app updates |
no equivalent; TestFlight / Google Play Console |
| AC_CODEPUSH |
react-native-code-push, codePush(App) |
Microsoft's standalone CodePush server, or drop OTA |
| AC_CLI |
appcenter-cli, appcenter distribute release in pipelines |
Azure Pipelines; Crashlytics symbol upload |
| AC_CONFIG |
appcenter-config.json, AppCenter-Config.plist |
google-services.json / GoogleService-Info.plist |
| AC_LOGLEVEL |
AppCenter.LogLevel |
-FIRDebugEnabled / setprop log.tag.FirebaseCrashlytics DEBUG |
Crashlytics limits the fixes respect: a maximum of 64 custom key-value pairs, each up to 1 kB, and 64kB of log per session.
The consent trap
If you port App Center's user-confirmation flow line by line, you usually delete ShouldAwaitUserConfirmation and move on. Crashlytics then sends reports automatically and the consent prompt no longer controls anything. The AC_CONSENT rule flags each confirmation call and gives the three Crashlytics calls that restore the flow.
Sample
The sample .NET MAUI App.cs in this repo gives 17 findings (11 errors, 5 warnings, 1 info). The migrated version of the same file gives 0.
Free and paid
Free, no key: open any C#, Kotlin, Java, Swift, Objective-C, JS/TS, Gradle, JSON or YAML file and the findings appear in the Problems panel with line numbers and the replacement call. The web version does the same for a pasted file.
With a licence key, the workspace migration report sweeps every project in the repo and exports a Markdown or CSV checklist to attach to the migration pull request: workspace migration report, $29 once.
Yardstick: Sentry Team is $26/mo billed annually; Firebase Crashlytics is no-cost; this lint covers the code you have to change to reach either one.
Source for the dates: Microsoft Learn, "Visual Studio App Center Retirement" (learn.microsoft.com/appcenter/retirement), last updated 2026-04-15.
