Build configuration for plugins for version 2026?

Dear all,

I am new to Intellij plugin development. I have InteliJ Platform Plugin Template 2.5.0 installed and create a new project using New - Project - IDE plugin. As this generates a project with values for Intelli 2025, I tried to manually bump them up:

# Supported build number ranges and IntelliJ Platform versions -> https://plugins.jetbrains.com/docs/intellij/build-number-ranges.html
pluginSinceBuild=261
# IntelliJ Platform Properties -> https://plugins.jetbrains.com/docs/intellij/tools-gradle-intellij-plugin.html#configuration-intellij-extension
platformVersion=2026.1.1
# Gradle Releases -> https://github.com/gradle/gradle/releases
gradleVersion=9.4.1

I end up with the following error

.\gradlew :runIde --stacktrace
Reusing configuration cache.

> Task :runIde FAILED
[0.010s][warning][cds] Archived non-system classes are disabled because the java.system.class.loader property is specified (value = "com.intellij.util.lang.PathClassLoader"). To use archived non-system classes, this property must not be set
Exception in thread "main" java.lang.ClassNotFoundException: kotlinx.coroutines.debug.internal.AgentPremain
        at com.intellij.util.lang.UrlClassLoader.findClass(UrlClassLoader.java:267)
        at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:557)
        at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:490)
        at java.instrument/sun.instrument.InstrumentationImpl.loadClassAndStartAgent(InstrumentationImpl.java:490)
        at java.instrument/sun.instrument.InstrumentationImpl.loadClassAndCallPremain(InstrumentationImpl.java:558)
*** java.lang.instrument ASSERTION FAILED ***: "!errorOutstanding" with message Outstanding error when calling method in invokeJavaAgentMainMethod at s\src\java.instrument\share\native\libinstrument\JPLISAgent.c line: 627
*** java.lang.instrument ASSERTION FAILED ***: "success" with message invokeJavaAgentMainMethod failed at s\src\java.instrument\share\native\libinstrument\JPLISAgent.c line: 466
*** java.lang.instrument ASSERTION FAILED ***: "result" with message agent load/premain call failed at s\src\java.instrument\share\native\libinstrument\JPLISAgent.c line: 429
FATAL ERROR in native method: processing of -javaagent failed, processJavaStart failed
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V  [jvm.dll+0x7c0cc9]  (no source info available)
V  [jvm.dll+0x78a49d]  (no source info available)
V  [jvm.dll+0x49cd3f]  (no source info available)
V  [jvm.dll+0x503c1a]  (no source info available)
C  [instrument.dll+0x27d8]  (no source info available)
V  [jvm.dll+0x662662]  (no source info available)
V  [jvm.dll+0x9b88dd]  (no source info available)
V  [jvm.dll+0x508a01]  (no source info available)
V  [jvm.dll+0x50a371]  (no source info available)
C  [jli.dll+0x541a]  (no source info available)
C  [ucrtbase.dll+0x37b0]  (no source info available)
C  [KERNEL32.DLL+0x2e8d7]  (no source info available)
C  [ntdll.dll+0x8c3fc]  (no source info available)


FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':runIde'.
> Process 'command 'C:\Users\stefan\.gradle\caches\9.2.1\transforms\16185a9c405081c9f16ba8f872f1f63e\workspace\transformed\idea-2026.1.1-win\jbr\bin\java.exe'' finished with non-zero exit value 1

* Try:
> Run with --info or --debug option to get more log output.
> Run with --scan to generate a Build Scan (powered by Develocity).
> Get more help at https://help.gradle.org.

* Exception is:
org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':runIde'.
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.lambda$executeIfValid$1(ExecuteActionsTaskExecuter.java:135)
        at org.gradle.internal.Try$Failure.ifSuccessfulOrElse(Try.java:288)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeIfValid(ExecuteActionsTaskExecuter.java:133)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:121)
        at org.gradle.api.internal.tasks.execution.ProblemsTaskPathTrackingTaskExecuter.execute(ProblemsTaskPathTrackingTaskExecuter.java:41)
        at org.gradle.api.internal.tasks.execution.FinalizePropertiesTaskExecuter.execute(FinalizePropertiesTaskExecuter.java:46)
        at org.gradle.api.internal.tasks.execution.ResolveTaskExecutionModeExecuter.execute(ResolveTaskExecutionModeExecuter.java:51)
        at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:57)
        at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:74)
        at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:36)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.executeTask(EventFiringTaskExecuter.java:77)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.call(EventFiringTaskExecuter.java:55)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.call(EventFiringTaskExecuter.java:52)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:209)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:204)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:66)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:166)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.call(DefaultBuildOperationRunner.java:53)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter.execute(EventFiringTaskExecuter.java:52)
        at org.gradle.execution.plan.DefaultNodeExecutor.executeLocalTaskNode(DefaultNodeExecutor.java:55)
        at org.gradle.execution.plan.DefaultNodeExecutor.execute(DefaultNodeExecutor.java:34)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:355)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:343)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.lambda$execute$0(DefaultTaskExecutionGraph.java:339)
        at org.gradle.internal.operations.CurrentBuildOperationRef.with(CurrentBuildOperationRef.java:84)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:339)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:328)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.execute(DefaultPlanExecutor.java:459)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.run(DefaultPlanExecutor.java:376)
        at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:64)
        at org.gradle.internal.concurrent.AbstractManagedExecutor$1.run(AbstractManagedExecutor.java:47)
Caused by: org.gradle.process.ProcessExecutionException: Process 'command 'C:\Users\stefan\.gradle\caches\9.2.1\transforms\16185a9c405081c9f16ba8f872f1f63e\workspace\transformed\idea-2026.1.1-win\jbr\bin\java.exe'' finished with non-zero exit value 1
        at org.gradle.process.internal.DefaultExecHandle$ExecResultImpl.assertNormalExitValue(DefaultExecHandle.java:450)
        at org.gradle.process.internal.DefaultJavaExecAction.execute(DefaultJavaExecAction.java:58)
        at org.gradle.api.tasks.JavaExec.exec(JavaExec.java:166)
        at org.jetbrains.intellij.platform.gradle.tasks.RunIdeTask.exec(RunIdeTask.kt:53)
        at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:125)
        at org.gradle.api.internal.project.taskfactory.StandardTaskAction.doExecute(StandardTaskAction.java:58)
        at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:51)
        at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:29)
        at org.gradle.api.internal.tasks.execution.TaskExecution$3.run(TaskExecution.java:252)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$1.execute(DefaultBuildOperationRunner.java:29)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$1.execute(DefaultBuildOperationRunner.java:26)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:66)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:166)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.run(DefaultBuildOperationRunner.java:47)
        at org.gradle.api.internal.tasks.execution.TaskExecution.executeAction(TaskExecution.java:237)
        at org.gradle.api.internal.tasks.execution.TaskExecution.executeActions(TaskExecution.java:220)
        at org.gradle.api.internal.tasks.execution.TaskExecution.executeWithPreviousOutputFiles(TaskExecution.java:203)
        at org.gradle.api.internal.tasks.execution.TaskExecution.execute(TaskExecution.java:170)
        at org.gradle.internal.execution.steps.ExecuteStep.executeInternal(ExecuteStep.java:105)
        at org.gradle.internal.execution.steps.ExecuteStep.access$000(ExecuteStep.java:44)
        at org.gradle.internal.execution.steps.ExecuteStep$1.call(ExecuteStep.java:59)
        at org.gradle.internal.execution.steps.ExecuteStep$1.call(ExecuteStep.java:56)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:209)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$CallableBuildOperationWorker.execute(DefaultBuildOperationRunner.java:204)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:66)
        at org.gradle.internal.operations.DefaultBuildOperationRunner$2.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:166)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.execute(DefaultBuildOperationRunner.java:59)
        at org.gradle.internal.operations.DefaultBuildOperationRunner.call(DefaultBuildOperationRunner.java:53)
        at org.gradle.internal.execution.steps.ExecuteStep.execute(ExecuteStep.java:56)
        at org.gradle.internal.execution.steps.ExecuteStep.execute(ExecuteStep.java:44)
        at org.gradle.internal.execution.steps.CancelExecutionStep.execute(CancelExecutionStep.java:42)
        at org.gradle.internal.execution.steps.TimeoutStep.executeWithoutTimeout(TimeoutStep.java:75)
        at org.gradle.internal.execution.steps.TimeoutStep.execute(TimeoutStep.java:55)
        at org.gradle.internal.execution.steps.PreCreateOutputParentsStep.execute(PreCreateOutputParentsStep.java:50)
        at org.gradle.internal.execution.steps.PreCreateOutputParentsStep.execute(PreCreateOutputParentsStep.java:28)
        at org.gradle.internal.execution.steps.RemovePreviousOutputsStep.execute(RemovePreviousOutputsStep.java:68)
        at org.gradle.internal.execution.steps.RemovePreviousOutputsStep.execute(RemovePreviousOutputsStep.java:38)
        at org.gradle.internal.execution.steps.BroadcastChangingOutputsStep.execute(BroadcastChangingOutputsStep.java:61)
        at org.gradle.internal.execution.steps.BroadcastChangingOutputsStep.execute(BroadcastChangingOutputsStep.java:26)
        at org.gradle.internal.execution.steps.CaptureOutputsAfterExecutionStep.execute(CaptureOutputsAfterExecutionStep.java:69)
        at org.gradle.internal.execution.steps.CaptureOutputsAfterExecutionStep.execute(CaptureOutputsAfterExecutionStep.java:46)
        at org.gradle.internal.execution.steps.ResolveInputChangesStep.execute(ResolveInputChangesStep.java:39)
        at org.gradle.internal.execution.steps.ResolveInputChangesStep.execute(ResolveInputChangesStep.java:28)
        at org.gradle.internal.execution.steps.BuildCacheStep.executeWithoutCache(BuildCacheStep.java:189)
        at org.gradle.internal.execution.steps.BuildCacheStep.lambda$execute$1(BuildCacheStep.java:75)
        at org.gradle.internal.Either$Right.fold(Either.java:176)
        at org.gradle.internal.execution.caching.CachingState.fold(CachingState.java:62)
        at org.gradle.internal.execution.steps.BuildCacheStep.execute(BuildCacheStep.java:73)
        at org.gradle.internal.execution.steps.BuildCacheStep.execute(BuildCacheStep.java:48)
        at org.gradle.internal.execution.steps.StoreExecutionStateStep.execute(StoreExecutionStateStep.java:46)
        at org.gradle.internal.execution.steps.StoreExecutionStateStep.execute(StoreExecutionStateStep.java:35)
        at org.gradle.internal.execution.steps.SkipUpToDateStep.executeBecause(SkipUpToDateStep.java:75)
        at org.gradle.internal.execution.steps.SkipUpToDateStep.lambda$execute$2(SkipUpToDateStep.java:53)
        at org.gradle.internal.execution.steps.SkipUpToDateStep.execute(SkipUpToDateStep.java:53)
        at org.gradle.internal.execution.steps.SkipUpToDateStep.execute(SkipUpToDateStep.java:35)
        at org.gradle.internal.execution.steps.legacy.MarkSnapshottingInputsFinishedStep.execute(MarkSnapshottingInputsFinishedStep.java:37)
        at org.gradle.internal.execution.steps.legacy.MarkSnapshottingInputsFinishedStep.execute(MarkSnapshottingInputsFinishedStep.java:27)
        at org.gradle.internal.execution.steps.ResolveIncrementalCachingStateStep.executeDelegate(ResolveIncrementalCachingStateStep.java:49)
        at org.gradle.internal.execution.steps.ResolveIncrementalCachingStateStep.executeDelegate(ResolveIncrementalCachingStateStep.java:27)
        at org.gradle.internal.execution.steps.AbstractResolveCachingStateStep.execute(AbstractResolveCachingStateStep.java:71)
        at org.gradle.internal.execution.steps.AbstractResolveCachingStateStep.execute(AbstractResolveCachingStateStep.java:39)
        at org.gradle.internal.execution.steps.ResolveChangesStep.execute(ResolveChangesStep.java:64)
        at org.gradle.internal.execution.steps.ResolveChangesStep.execute(ResolveChangesStep.java:35)
        at org.gradle.internal.execution.steps.ValidateStep.execute(ValidateStep.java:62)
        at org.gradle.internal.execution.steps.ValidateStep.execute(ValidateStep.java:40)
        at org.gradle.internal.execution.steps.AbstractCaptureStateBeforeExecutionStep.execute(AbstractCaptureStateBeforeExecutionStep.java:76)
        at org.gradle.internal.execution.steps.AbstractCaptureStateBeforeExecutionStep.execute(AbstractCaptureStateBeforeExecutionStep.java:45)
        at org.gradle.internal.execution.steps.AbstractSkipEmptyWorkStep.executeWithNonEmptySources(AbstractSkipEmptyWorkStep.java:136)
        at org.gradle.internal.execution.steps.AbstractSkipEmptyWorkStep.execute(AbstractSkipEmptyWorkStep.java:61)
        at org.gradle.internal.execution.steps.AbstractSkipEmptyWorkStep.execute(AbstractSkipEmptyWorkStep.java:38)
        at org.gradle.internal.execution.steps.legacy.MarkSnapshottingInputsStartedStep.execute(MarkSnapshottingInputsStartedStep.java:38)
        at org.gradle.internal.execution.steps.LoadPreviousExecutionStateStep.execute(LoadPreviousExecutionStateStep.java:36)
        at org.gradle.internal.execution.steps.LoadPreviousExecutionStateStep.execute(LoadPreviousExecutionStateStep.java:23)
        at org.gradle.internal.execution.steps.HandleStaleOutputsStep.execute(HandleStaleOutputsStep.java:75)
        at org.gradle.internal.execution.steps.HandleStaleOutputsStep.execute(HandleStaleOutputsStep.java:41)
        at org.gradle.internal.execution.steps.AssignMutableWorkspaceStep.lambda$execute$0(AssignMutableWorkspaceStep.java:35)
        at org.gradle.api.internal.tasks.execution.TaskExecution$4.withWorkspace(TaskExecution.java:297)
        at org.gradle.internal.execution.steps.AssignMutableWorkspaceStep.execute(AssignMutableWorkspaceStep.java:31)
        at org.gradle.internal.execution.steps.AssignMutableWorkspaceStep.execute(AssignMutableWorkspaceStep.java:22)
        at org.gradle.internal.execution.steps.ChoosePipelineStep.execute(ChoosePipelineStep.java:40)
        at org.gradle.internal.execution.steps.ChoosePipelineStep.execute(ChoosePipelineStep.java:23)
        at org.gradle.internal.execution.steps.ExecuteWorkBuildOperationFiringStep.lambda$execute$2(ExecuteWorkBuildOperationFiringStep.java:67)
        at org.gradle.internal.execution.steps.ExecuteWorkBuildOperationFiringStep.execute(ExecuteWorkBuildOperationFiringStep.java:67)
        at org.gradle.internal.execution.steps.ExecuteWorkBuildOperationFiringStep.execute(ExecuteWorkBuildOperationFiringStep.java:39)
        at org.gradle.internal.execution.steps.IdentityCacheStep.execute(IdentityCacheStep.java:46)
        at org.gradle.internal.execution.steps.IdentityCacheStep.execute(IdentityCacheStep.java:34)
        at org.gradle.internal.execution.steps.IdentifyStep.execute(IdentifyStep.java:44)
        at org.gradle.internal.execution.steps.IdentifyStep.execute(IdentifyStep.java:31)
        at org.gradle.internal.execution.impl.DefaultExecutionEngine$1.execute(DefaultExecutionEngine.java:64)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeIfValid(ExecuteActionsTaskExecuter.java:132)
        ... 30 more


BUILD FAILED in 1s
11 actionable tasks: 2 executed, 9 up-to-date
Configuration cache entry reused.

Leading to my questions:

  1. Why do the plugin templates still use 2025?

  2. How to develop plugins for 2026?

i also had to update libs.versions.toml

[versions]
intellijPlatform = "2.14.0"
kotlin = "2.3.21"

and gradle-wrapper.properties

distributionUrl=https\://services.gradle.org/distributions/gradle-9.4.0-bin.zip

then it compiled fine.

I still don’t understand why the template defaults to 2025.

You build a plugin against a specific platform (IDE) Version, defined by platformVersion. It’s like adding IDE’s classes to the classpath when compiling your plugin. It was set to 2025 because we want to build against this minimal supported IDE version, defined by pluginSinceBuild. You can still build against a more recent platform if you want.
The current IntelliJ Platform Plugin Template is configured to build plugins that will be compatible with 2025+ IDEs.
Nota: you should create your plugin via GitHub - JetBrains/intellij-platform-plugin-template: Template repository for creating plugins for IntelliJ Platform · GitHub. It’s more up to date.

Jonathan is absolutely right, the template uses the recommended base version to make your plugin visible to more users, for instance, when they use not the most recent stable version.

We update this base version with new major releases coming, but you can switch to more modern API level any time, just do not forget to increase sinceBuild as well.

@jonathanlermitage.1 @yuriy.artamonov Got it, thanks for explaining! About the template I tried some days agos and had issues, switched over to the template in the IDE which worked fine :slight_smile: