diff --git a/libraries/stdlib/js-ir/build.gradle b/libraries/stdlib/js-ir/build.gradle
index d454212a139..991e26b2d02 100644
--- a/libraries/stdlib/js-ir/build.gradle
+++ b/libraries/stdlib/js-ir/build.gradle
@@ -143,10 +143,12 @@ archivesBaseName = 'kotlin-stdlib-js-ir'
 
 jar {
     manifestAttributes(manifest, project, 'Main')
+    duplicatesStrategy = DuplicatesStrategy.FAIL
 }
 
 task sourcesJar(type: Jar, dependsOn: classes) {
     classifier = 'sources'
+    duplicatesStrategy = DuplicatesStrategy.FAIL
     from (sourceSets.main.allSource)
 }
 
diff --git a/libraries/stdlib/js-ir/runtime/core.kt b/libraries/stdlib/js-ir/runtime/coreRuntime.kt
similarity index 100%
rename from libraries/stdlib/js-ir/runtime/core.kt
rename to libraries/stdlib/js-ir/runtime/coreRuntime.kt
diff --git a/libraries/stdlib/js-ir/src/kotlin/math.kt b/libraries/stdlib/js-ir/src/kotlin/math_js-ir.kt
similarity index 100%
rename from libraries/stdlib/js-ir/src/kotlin/math.kt
rename to libraries/stdlib/js-ir/src/kotlin/math_js-ir.kt
diff --git a/libraries/stdlib/js-ir/src/kotlin/numbers.kt b/libraries/stdlib/js-ir/src/kotlin/numbers_js-ir.kt
similarity index 100%
rename from libraries/stdlib/js-ir/src/kotlin/numbers.kt
rename to libraries/stdlib/js-ir/src/kotlin/numbers_js-ir.kt
diff --git a/libraries/stdlib/js-ir/src/kotlin/text/numberConversions.kt b/libraries/stdlib/js-ir/src/kotlin/text/numberConversions_js-ir.kt
similarity index 100%
rename from libraries/stdlib/js-ir/src/kotlin/text/numberConversions.kt
rename to libraries/stdlib/js-ir/src/kotlin/text/numberConversions_js-ir.kt
diff --git a/libraries/stdlib/js-v1/build.gradle b/libraries/stdlib/js-v1/build.gradle
index c06e5918b88..aeab56a349f 100644
--- a/libraries/stdlib/js-v1/build.gradle
+++ b/libraries/stdlib/js-v1/build.gradle
@@ -308,6 +308,7 @@ task mergedJar(type: Jar, dependsOn: compileJs) {
 task sourcesJar(type: Jar, dependsOn: compileJs) {
     classifier = 'sources'
     includeEmptyDirs false
+    duplicatesStrategy = DuplicatesStrategy.FAIL
     from(sourceSets.builtins.allSource) {
         into 'kotlin'
     }
diff --git a/libraries/stdlib/js-v1/src/kotlin/math.kt b/libraries/stdlib/js-v1/src/kotlin/math_js-v1.kt
similarity index 100%
rename from libraries/stdlib/js-v1/src/kotlin/math.kt
rename to libraries/stdlib/js-v1/src/kotlin/math_js-v1.kt
diff --git a/libraries/stdlib/js-v1/src/kotlin/numbers.kt b/libraries/stdlib/js-v1/src/kotlin/numbers_js-v1.kt
similarity index 100%
rename from libraries/stdlib/js-v1/src/kotlin/numbers.kt
rename to libraries/stdlib/js-v1/src/kotlin/numbers_js-v1.kt
diff --git a/libraries/stdlib/js-v1/src/kotlin/text/numberConversions.kt b/libraries/stdlib/js-v1/src/kotlin/text/numberConversions_js-v1.kt
similarity index 100%
rename from libraries/stdlib/js-v1/src/kotlin/text/numberConversions.kt
rename to libraries/stdlib/js-v1/src/kotlin/text/numberConversions_js-v1.kt