diff --git a/compiler/cli/resources/META-INF/services/org.jetbrains.kotlin.diagnostics.rendering.DefaultErrorMessages$Extension b/compiler/cli/resources/META-INF/services/org.jetbrains.kotlin.diagnostics.rendering.DefaultErrorMessages$Extension
index 5da1cf79980..a7a0ec33d13 100644
--- a/compiler/cli/resources/META-INF/services/org.jetbrains.kotlin.diagnostics.rendering.DefaultErrorMessages$Extension
+++ b/compiler/cli/resources/META-INF/services/org.jetbrains.kotlin.diagnostics.rendering.DefaultErrorMessages$Extension
@@ -1,5 +1,4 @@
 # Note that this file is also present in idea/src/META-INF/services
 org.jetbrains.kotlin.resolve.jvm.diagnostics.DefaultErrorMessagesJvm
 org.jetbrains.kotlin.js.resolve.diagnostics.DefaultErrorMessagesJs
-org.jetbrains.kotlin.fir.analysis.diagnostics.FirDefaultErrorMessages
-org.jetbrains.kotlin.resolve.konan.diagnostics.DefaultErrorMessagesNative
\ No newline at end of file
+org.jetbrains.kotlin.resolve.konan.diagnostics.DefaultErrorMessagesNative
diff --git a/compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/FirKotlinToJvmBytecodeCompiler.kt b/compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/FirKotlinToJvmBytecodeCompiler.kt
index 4f5a38b30a5..cc77a428f4c 100644
--- a/compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/FirKotlinToJvmBytecodeCompiler.kt
+++ b/compiler/cli/src/org/jetbrains/kotlin/cli/jvm/compiler/FirKotlinToJvmBytecodeCompiler.kt
@@ -147,10 +147,11 @@ object FirKotlinToJvmBytecodeCompiler {
 
             firAnalyzerFacade.runResolution()
             val firDiagnostics = firAnalyzerFacade.runCheckers().values.flatten()
-            AnalyzerWithCompilerReport.reportDiagnostics(
-                SimpleGenericDiagnostics(firDiagnostics),
-                environment.messageCollector
-            )
+            // TODO
+//            AnalyzerWithCompilerReport.reportDiagnostics(
+//                SimpleGenericDiagnostics(firDiagnostics),
+//                environment.messageCollector
+//            )
             performanceManager?.notifyAnalysisFinished()
 
             if (syntaxErrors || firDiagnostics.any { it.severity == Severity.ERROR }) {
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDefaultErrorMessages.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDefaultErrorMessages.kt
index 91f10dba8d7..0dd188a5529 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDefaultErrorMessages.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDefaultErrorMessages.kt
@@ -377,11 +377,7 @@ import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.WRONG_SETTER_PARA
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.WRONG_SETTER_RETURN_TYPE
 
 @Suppress("unused")
-class FirDefaultErrorMessages : DefaultErrorMessages.Extension {
-    override fun getMap(): DiagnosticFactoryToRendererMap {
-        return MAP.psiDiagnosticMap
-    }
-
+class FirDefaultErrorMessages {
     companion object {
         fun getRendererForDiagnostic(diagnostic: FirDiagnostic<*>): FirDiagnosticRenderer<*> {
             val factory = diagnostic.factory
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnostic.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnostic.kt
index e0efef3834b..1bf8907bcb2 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnostic.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnostic.kt
@@ -8,25 +8,23 @@ package org.jetbrains.kotlin.fir.analysis.diagnostics
 import com.intellij.openapi.util.TextRange
 import com.intellij.psi.PsiElement
 import com.intellij.psi.PsiFile
-import org.jetbrains.kotlin.diagnostics.Diagnostic
 import org.jetbrains.kotlin.diagnostics.Severity
-import org.jetbrains.kotlin.diagnostics.UnboundDiagnostic
 import org.jetbrains.kotlin.fir.FirLightSourceElement
 import org.jetbrains.kotlin.fir.FirPsiSourceElement
 import org.jetbrains.kotlin.fir.FirSourceElement
 
 // ------------------------------ diagnostics ------------------------------
 
-sealed class FirDiagnostic<out E : FirSourceElement> : UnboundDiagnostic {
+sealed class FirDiagnostic<out E : FirSourceElement> {
     abstract val element: E
-    abstract override val severity: Severity
-    abstract override val factory: AbstractFirDiagnosticFactory<*, *>
+    abstract val severity: Severity
+    abstract val factory: AbstractFirDiagnosticFactory<*, *>
     abstract val positioningStrategy: SourceElementPositioningStrategy<*>
 
-    override val textRanges: List<TextRange>
+    val textRanges: List<TextRange>
         get() = positioningStrategy.markDiagnostic(this)
 
-    override val isValid: Boolean
+    val isValid: Boolean
         get() = positioningStrategy.isValid(element)
 }
 
@@ -62,13 +60,16 @@ sealed class FirDiagnosticWithParameters4<out E : FirSourceElement, A, B, C, D>
 
 // ------------------------------ psi diagnostics ------------------------------
 
-interface FirPsiDiagnostic<P : PsiElement> : Diagnostic {
+interface FirPsiDiagnostic<P : PsiElement> {
+    val factory: AbstractFirDiagnosticFactory<*, P>
     val element: FirPsiSourceElement<P>
+    val textRanges: List<TextRange>
+    val severity: Severity
 
-    override val psiElement: PsiElement
+    val psiElement: PsiElement
         get() = element.psi
 
-    override val psiFile: PsiFile
+    val psiFile: PsiFile
         get() = psiElement.containingFile
 }
 
@@ -119,7 +120,7 @@ data class FirPsiDiagnosticWithParameters4<P : PsiElement, A, B, C, D>(
 
 // ------------------------------ light tree diagnostics ------------------------------
 
-interface FirLightDiagnostic : UnboundDiagnostic {
+interface FirLightDiagnostic {
     val element: FirLightSourceElement
 }
 
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactory.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactory.kt
index 0ebdd8edb9c..2858a1473da 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactory.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactory.kt
@@ -1,16 +1,9 @@
-/*
- * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
 @file:Suppress("UNCHECKED_CAST")
 
 package org.jetbrains.kotlin.fir.analysis.diagnostics
 
 import com.intellij.psi.PsiElement
-import org.jetbrains.kotlin.diagnostics.DiagnosticFactory
 import org.jetbrains.kotlin.diagnostics.Severity
-import org.jetbrains.kotlin.diagnostics.rendering.DiagnosticRenderer
 import org.jetbrains.kotlin.fir.FirLightSourceElement
 import org.jetbrains.kotlin.fir.FirPsiSourceElement
 import org.jetbrains.kotlin.fir.FirSourceElement
@@ -19,16 +12,11 @@ import org.jetbrains.kotlin.fir.FirSourceElement
 annotation class InternalDiagnosticFactoryMethod
 
 sealed class AbstractFirDiagnosticFactory<D : FirDiagnostic<*>, P : PsiElement>(
-    override val name: String,
-    override val severity: Severity,
+    val name: String,
+    val severity: Severity,
     val defaultPositioningStrategy: SourceElementPositioningStrategy<P>,
-) : DiagnosticFactory<D>(name, severity) {
+) {
     abstract val firRenderer: FirDiagnosticRenderer<D>
-
-    override var defaultRenderer: DiagnosticRenderer<D>?
-        get() = firRenderer
-        set(_) {
-        }
 }
 
 class FirDiagnosticFactory0<P : PsiElement>(
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactoryToRendererMap.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactoryToRendererMap.kt
index 7ec913c5e20..ef9745a9908 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactoryToRendererMap.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactoryToRendererMap.kt
@@ -5,12 +5,10 @@
 
 package org.jetbrains.kotlin.fir.analysis.diagnostics
 
-import org.jetbrains.kotlin.diagnostics.rendering.DiagnosticFactoryToRendererMap
 import org.jetbrains.kotlin.diagnostics.rendering.DiagnosticParameterRenderer
 
 class FirDiagnosticFactoryToRendererMap(val name: String) {
     private val renderersMap: MutableMap<AbstractFirDiagnosticFactory<*, *>, FirDiagnosticRenderer<*>> = mutableMapOf()
-    val psiDiagnosticMap: DiagnosticFactoryToRendererMap = DiagnosticFactoryToRendererMap()
 
     operator fun get(factory: AbstractFirDiagnosticFactory<*, *>): FirDiagnosticRenderer<*>? = renderersMap[factory]
 
@@ -58,6 +56,5 @@ class FirDiagnosticFactoryToRendererMap(val name: String) {
 
     private fun put(factory: AbstractFirDiagnosticFactory<*, *>, renderer: FirDiagnosticRenderer<*>) {
         renderersMap[factory] = renderer
-        psiDiagnosticMap.put(factory, renderer)
     }
 }
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticRenderer.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticRenderer.kt
index 0b66f31ac14..0042c6a07b0 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticRenderer.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticRenderer.kt
@@ -6,11 +6,11 @@
 package org.jetbrains.kotlin.fir.analysis.diagnostics
 
 import org.jetbrains.kotlin.diagnostics.rendering.*
+import java.text.MessageFormat
 
-interface FirDiagnosticRenderer<D : FirDiagnostic<*>> : DiagnosticRenderer<D> {
-    override fun render(diagnostic: D): String
-
-    override fun renderParameters(diagnostic: D): Array<out Any?>
+sealed interface FirDiagnosticRenderer<D : FirDiagnostic<*>> {
+    fun render(diagnostic: D): String
+    fun renderParameters(diagnostic: D): Array<out Any?>
 }
 
 class SimpleFirDiagnosticRenderer(private val message: String) : FirDiagnosticRenderer<FirSimpleDiagnostic<*>> {
@@ -19,13 +19,19 @@ class SimpleFirDiagnosticRenderer(private val message: String) : FirDiagnosticRe
     }
 
     override fun renderParameters(diagnostic: FirSimpleDiagnostic<*>): Array<out Any?> {
-        return arrayOf()
+        return emptyArray()
     }
 }
 
 sealed class AbstractFirDiagnosticWithParametersRenderer<D : FirDiagnostic<*>>(
     protected val message: String
-) : FirDiagnosticRenderer<D>, AbstractDiagnosticWithParametersRenderer<D>(message)
+) : FirDiagnosticRenderer<D> {
+    private val messageFormat = MessageFormat(message)
+
+    final override fun render(diagnostic: D): String {
+        return messageFormat.format(renderParameters(diagnostic))
+    }
+}
 
 class FirDiagnosticWithParameters1Renderer<A>(
     message: String,
diff --git a/idea/resources/META-INF/services/org.jetbrains.kotlin.diagnostics.rendering.DefaultErrorMessages$Extension b/idea/resources/META-INF/services/org.jetbrains.kotlin.diagnostics.rendering.DefaultErrorMessages$Extension
index d40ff3ceb13..99ce03918a8 100644
--- a/idea/resources/META-INF/services/org.jetbrains.kotlin.diagnostics.rendering.DefaultErrorMessages$Extension
+++ b/idea/resources/META-INF/services/org.jetbrains.kotlin.diagnostics.rendering.DefaultErrorMessages$Extension
@@ -1,5 +1,4 @@
 # Note that this file is also present in compiler/cli/src/META-INF/services
 org.jetbrains.kotlin.resolve.jvm.diagnostics.DefaultErrorMessagesJvm
 org.jetbrains.kotlin.js.resolve.diagnostics.DefaultErrorMessagesJs
-org.jetbrains.kotlin.fir.analysis.diagnostics.FirDefaultErrorMessages
-org.jetbrains.kotlin.resolve.konan.diagnostics.DefaultErrorMessagesNative
\ No newline at end of file
+org.jetbrains.kotlin.resolve.konan.diagnostics.DefaultErrorMessagesNative