diff --git a/idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/KotlinFirCompletionContributor.kt b/idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/KotlinFirCompletionContributor.kt
index 9627abc736c..a3dca8ad704 100644
--- a/idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/KotlinFirCompletionContributor.kt
+++ b/idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/KotlinFirCompletionContributor.kt
@@ -10,6 +10,8 @@ import com.intellij.patterns.PlatformPatterns
 import com.intellij.patterns.PsiJavaPatterns
 import com.intellij.util.ProcessingContext
 import org.jetbrains.kotlin.idea.caches.project.getModuleInfo
+import org.jetbrains.kotlin.idea.completion.checkers.CompletionVisibilityChecker
+import org.jetbrains.kotlin.idea.completion.checkers.ExtensionApplicabilityChecker
 import org.jetbrains.kotlin.idea.completion.context.FirBasicCompletionContext
 import org.jetbrains.kotlin.idea.completion.context.FirNameReferencePositionContext
 import org.jetbrains.kotlin.idea.completion.context.FirPositionCompletionContextDetector
@@ -25,7 +27,6 @@ import org.jetbrains.kotlin.idea.frontend.api.components.KtScopeContext
 import org.jetbrains.kotlin.idea.frontend.api.scopes.KtCompositeScope
 import org.jetbrains.kotlin.idea.frontend.api.scopes.KtScope
 import org.jetbrains.kotlin.idea.frontend.api.symbols.*
-import org.jetbrains.kotlin.idea.frontend.api.symbols.markers.KtSymbolWithVisibility
 import org.jetbrains.kotlin.idea.frontend.api.types.KtClassType
 import org.jetbrains.kotlin.idea.frontend.api.types.KtType
 import org.jetbrains.kotlin.lexer.KtTokens
@@ -104,22 +105,6 @@ private object KotlinFirCompletionProvider : CompletionProvider<CompletionParame
     }
 }
 
-internal fun interface ExtensionApplicabilityChecker {
-    fun KtAnalysisSession.isApplicable(symbol: KtCallableSymbol): Boolean
-}
-
-internal fun interface CompletionVisibilityChecker {
-    fun KtAnalysisSession.isVisible(symbol: KtSymbolWithVisibility): Boolean
-
-    fun KtAnalysisSession.isVisible(symbol: KtCallableSymbol): Boolean {
-        return symbol !is KtSymbolWithVisibility || isVisible(symbol as KtSymbolWithVisibility)
-    }
-
-    fun KtAnalysisSession.isVisible(symbol: KtClassifierSymbol): Boolean {
-        return symbol !is KtSymbolWithVisibility || isVisible(symbol as KtSymbolWithVisibility)
-    }
-}
-
 /**
  * Currently, this class is responsible for collecting all possible completion variants.
  *
diff --git a/idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/checkers/CompletionVisibilityChecker.kt b/idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/checkers/CompletionVisibilityChecker.kt
new file mode 100644
index 00000000000..d792e5f9d9a
--- /dev/null
+++ b/idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/checkers/CompletionVisibilityChecker.kt
@@ -0,0 +1,23 @@
+/*
+ * Copyright 2010-2021 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.
+ */
+
+package org.jetbrains.kotlin.idea.completion.checkers
+
+import org.jetbrains.kotlin.idea.frontend.api.KtAnalysisSession
+import org.jetbrains.kotlin.idea.frontend.api.symbols.KtCallableSymbol
+import org.jetbrains.kotlin.idea.frontend.api.symbols.KtClassifierSymbol
+import org.jetbrains.kotlin.idea.frontend.api.symbols.markers.KtSymbolWithVisibility
+
+internal fun interface CompletionVisibilityChecker {
+    fun KtAnalysisSession.isVisible(symbol: KtSymbolWithVisibility): Boolean
+
+    fun KtAnalysisSession.isVisible(symbol: KtCallableSymbol): Boolean {
+        return symbol !is KtSymbolWithVisibility || isVisible(symbol as KtSymbolWithVisibility)
+    }
+
+    fun KtAnalysisSession.isVisible(symbol: KtClassifierSymbol): Boolean {
+        return symbol !is KtSymbolWithVisibility || isVisible(symbol as KtSymbolWithVisibility)
+    }
+}
\ No newline at end of file
diff --git a/idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/checkers/ExtensionApplicabilityChecker.kt b/idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/checkers/ExtensionApplicabilityChecker.kt
new file mode 100644
index 00000000000..670271dbe08
--- /dev/null
+++ b/idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/checkers/ExtensionApplicabilityChecker.kt
@@ -0,0 +1,13 @@
+/*
+ * Copyright 2010-2021 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.
+ */
+
+package org.jetbrains.kotlin.idea.completion.checkers
+
+import org.jetbrains.kotlin.idea.frontend.api.KtAnalysisSession
+import org.jetbrains.kotlin.idea.frontend.api.symbols.KtCallableSymbol
+
+internal fun interface ExtensionApplicabilityChecker {
+    fun KtAnalysisSession.isApplicable(symbol: KtCallableSymbol): Boolean
+}
\ No newline at end of file
diff --git a/idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/contributors/FirClassifierCompletionContributor.kt b/idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/contributors/FirClassifierCompletionContributor.kt
index 4826842ccb6..75b81ffd789 100644
--- a/idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/contributors/FirClassifierCompletionContributor.kt
+++ b/idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/contributors/FirClassifierCompletionContributor.kt
@@ -5,7 +5,7 @@
 
 package org.jetbrains.kotlin.idea.completion.contributors
 
-import org.jetbrains.kotlin.idea.completion.CompletionVisibilityChecker
+import org.jetbrains.kotlin.idea.completion.checkers.CompletionVisibilityChecker
 import org.jetbrains.kotlin.idea.completion.context.FirBasicCompletionContext
 import org.jetbrains.kotlin.idea.fir.low.level.api.IndexHelper
 import org.jetbrains.kotlin.idea.frontend.api.KtAnalysisSession