diff --git a/plugins/license-gather-plugin/src/main/kotlin/com/github/vlsi/gradle/license/api/LicenseExpression.kt b/plugins/license-gather-plugin/src/main/kotlin/com/github/vlsi/gradle/license/api/LicenseExpression.kt
index c4a455b..7a20bb6 100644
--- a/plugins/license-gather-plugin/src/main/kotlin/com/github/vlsi/gradle/license/api/LicenseExpression.kt
+++ b/plugins/license-gather-plugin/src/main/kotlin/com/github/vlsi/gradle/license/api/LicenseExpression.kt
@@ -160,7 +160,7 @@ fun LicenseExpression.weight(): Int =
         is JustLicense -> 1
         is OrLaterLicense -> 2
         is WithException -> license.weight() + 1
-        is ConjunctionLicenseExpression -> licenses.map { it.weight() + 1 }.max() ?: 1
-        is DisjunctionLicenseExpression -> licenses.map { it.weight() + 1 }.max() ?: 1
+        is ConjunctionLicenseExpression -> licenses.map { it.weight() + 1 }.maxOrNull() ?: 1
+        is DisjunctionLicenseExpression -> licenses.map { it.weight() + 1 }.maxOrNull() ?: 1
         else -> TODO("Unexpected expression: ${this::class.simpleName}: $this")
     }
diff --git a/plugins/stage-vote-release-plugin/src/main/kotlin/com/github/vlsi/gradle/release/Apache2LicenseInterpreter.kt b/plugins/stage-vote-release-plugin/src/main/kotlin/com/github/vlsi/gradle/release/Apache2LicenseInterpreter.kt
index 5a5ce74..64b80f8 100644
--- a/plugins/stage-vote-release-plugin/src/main/kotlin/com/github/vlsi/gradle/release/Apache2LicenseInterpreter.kt
+++ b/plugins/stage-vote-release-plugin/src/main/kotlin/com/github/vlsi/gradle/release/Apache2LicenseInterpreter.kt
@@ -41,9 +41,9 @@ class Apache2LicenseInterpreter {
         return when (e) {
             is DisjunctionLicenseExpression ->
                 // A or X => A
-                e.unordered.map { eval(it) }.min()
+                e.unordered.map { eval(it) }.minOrNull()
             is ConjunctionLicenseExpression ->
-                e.unordered.map { eval(it) }.max()
+                e.unordered.map { eval(it) }.maxOrNull()
             else -> null
         } ?: AsfLicenseCategory.UNKNOWN
     }
diff --git a/plugins/stage-vote-release-plugin/src/main/kotlin/com/github/vlsi/gradle/release/StageVoteReleasePlugin.kt b/plugins/stage-vote-release-plugin/src/main/kotlin/com/github/vlsi/gradle/release/StageVoteReleasePlugin.kt
index 5d849a6..0b8e2bf 100644
--- a/plugins/stage-vote-release-plugin/src/main/kotlin/com/github/vlsi/gradle/release/StageVoteReleasePlugin.kt
+++ b/plugins/stage-vote-release-plugin/src/main/kotlin/com/github/vlsi/gradle/release/StageVoteReleasePlugin.kt
@@ -675,7 +675,7 @@ class StageVoteReleasePlugin @Inject constructor(private val instantiator: Insta
                     Pair(listOf(), mapOf())
                 }
 
-                val svnStagingRevision = stagedFiles.map { it.commit.revision }.max() ?: 0
+                val svnStagingRevision = stagedFiles.map { it.commit.revision }.maxOrNull() ?: 0
 
                 val releaseParams = ReleaseParams(
                     tlp = releaseExt.tlp.get(),