diff --git a/build.gradle.kts b/build.gradle.kts
index 9db78013..e577b9d2 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -4,7 +4,7 @@ plugins {
 
 allprojects {
     group = "space.kscience"
-    version = "0.6.0-dev-3"
+    version = "0.6.0-dev-4"
     repositories{
         mavenCentral()
     }
diff --git a/dataforge-data/src/commonMain/kotlin/space/kscience/dataforge/actions/MapAction.kt b/dataforge-data/src/commonMain/kotlin/space/kscience/dataforge/actions/MapAction.kt
index 8aae6be8..891e99f0 100644
--- a/dataforge-data/src/commonMain/kotlin/space/kscience/dataforge/actions/MapAction.kt
+++ b/dataforge-data/src/commonMain/kotlin/space/kscience/dataforge/actions/MapAction.kt
@@ -36,7 +36,10 @@ public class MapActionBuilder<T, R>(
 
     public lateinit var result: suspend ActionEnv.(T) -> R
 
-    internal fun <R1 : R> result(outputType: KType, f: suspend ActionEnv.(T) -> R1) {
+    /**
+     * Set unsafe [outputType] for the resulting data. Be sure that it is correct.
+     */
+    public fun <R1 : R> result(outputType: KType, f: suspend ActionEnv.(T) -> R1) {
         this.outputType = outputType
         result = f;
     }
diff --git a/dataforge-io/dataforge-io-yaml/src/commonMain/kotlin/space/kscience/dataforge/io/yaml/FrontMatterEnvelopeFormat.kt b/dataforge-io/dataforge-io-yaml/src/commonMain/kotlin/space/kscience/dataforge/io/yaml/FrontMatterEnvelopeFormat.kt
index 2734ebd9..7f705a71 100644
--- a/dataforge-io/dataforge-io-yaml/src/commonMain/kotlin/space/kscience/dataforge/io/yaml/FrontMatterEnvelopeFormat.kt
+++ b/dataforge-io/dataforge-io-yaml/src/commonMain/kotlin/space/kscience/dataforge/io/yaml/FrontMatterEnvelopeFormat.kt
@@ -14,7 +14,6 @@ import space.kscience.dataforge.misc.DFExperimental
 import space.kscience.dataforge.names.Name
 import space.kscience.dataforge.names.plus
 
-@DFExperimental
 public class FrontMatterEnvelopeFormat(
     private val io: IOPlugin,
     private val meta: Meta = Meta.EMPTY,
@@ -101,7 +100,7 @@ public class FrontMatterEnvelopeFormat(
             envelope: Envelope,
             metaFormatFactory: MetaFormatFactory,
             formatMeta: Meta,
-        ): Unit = FrontMatterEnvelopeFormat.default.writeEnvelope(output, envelope, metaFormatFactory, formatMeta)
+        ): Unit = default.writeEnvelope(output, envelope, metaFormatFactory, formatMeta)
 
 
         override fun readObject(input: Input): Envelope = default.readObject(input)
diff --git a/dataforge-io/dataforge-io-yaml/src/commonMain/kotlin/space/kscience/dataforge/io/yaml/YamlMetaFormat.kt b/dataforge-io/dataforge-io-yaml/src/commonMain/kotlin/space/kscience/dataforge/io/yaml/YamlMetaFormat.kt
index 148a2b87..b7c7c3e4 100644
--- a/dataforge-io/dataforge-io-yaml/src/commonMain/kotlin/space/kscience/dataforge/io/yaml/YamlMetaFormat.kt
+++ b/dataforge-io/dataforge-io-yaml/src/commonMain/kotlin/space/kscience/dataforge/io/yaml/YamlMetaFormat.kt
@@ -95,7 +95,6 @@ public fun YamlMap.toMeta(): Meta = YamlMeta(this)
 /**
  * Represent meta as Yaml
  */
-@DFExperimental
 public class YamlMetaFormat(private val meta: Meta) : MetaFormat {
 
     override fun writeMeta(output: Output, meta: Meta, descriptor: MetaDescriptor?) {
diff --git a/dataforge-io/dataforge-io-yaml/src/commonMain/kotlin/space/kscience/dataforge/io/yaml/YamlPlugin.kt b/dataforge-io/dataforge-io-yaml/src/commonMain/kotlin/space/kscience/dataforge/io/yaml/YamlPlugin.kt
index dea3a38c..c26487a5 100644
--- a/dataforge-io/dataforge-io-yaml/src/commonMain/kotlin/space/kscience/dataforge/io/yaml/YamlPlugin.kt
+++ b/dataforge-io/dataforge-io-yaml/src/commonMain/kotlin/space/kscience/dataforge/io/yaml/YamlPlugin.kt
@@ -13,7 +13,6 @@ import space.kscience.dataforge.names.Name
 import space.kscience.dataforge.names.asName
 import kotlin.reflect.KClass
 
-@DFExperimental
 public class YamlPlugin(meta: Meta) : AbstractPlugin(meta) {
     public val io: IOPlugin by require(IOPlugin)
 
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index ffed3a25..aa991fce 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.2-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.4.2-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists