diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index 95f37b118..6476d7357 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -11,7 +11,7 @@ dataframe = "0.13.1"
 serialization = "1.6.3"
 datetime = "0.5.0"
 html = "0.11.0"
-statistics = "0.3.0-dev-20"
+statistics = "0.3.0-dev-21"
 letsPlot = "4.6.0"
 letsPlotImage = "4.2.0"
 mockk = "1.13.10"
diff --git a/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/accessors.kt b/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/accessors.kt
index 1937b37dd..197732123 100644
--- a/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/accessors.kt
+++ b/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/accessors.kt
@@ -7,42 +7,42 @@ import org.jetbrains.kotlinx.kandy.ir.feature.PlotFeature
 @PublishedApi
 internal val LayerBuilder.datasetBuilder: DatasetBuilder
         get() = when (this) {
-            is LayerBuilderImpl -> datasetBuilder
-            is SingleLayerPlotBuilder -> datasetBuilder
+            is LayerBuilderImpl -> this.datasetBuilder
+            is SingleLayerPlotBuilder -> this.datasetBuilder
         }
 
 @PublishedApi
 internal val LayerBuilder.layerFeatures: MutableMap<FeatureName, LayerFeature>
     get() = when (this) {
-        is LayerBuilderImpl -> layerFeatures
-        is SingleLayerPlotBuilder -> layerFeatures
+        is LayerBuilderImpl -> this.layerFeatures
+        is SingleLayerPlotBuilder -> this.layerFeatures
     }
 
 @PublishedApi
 internal val LayerBuilder.bindingHandler: BindingHandler
     get() = when (this) {
-        is LayerBuilderImpl -> bindingHandler
-        is SingleLayerPlotBuilder -> bindingHandler
+        is LayerBuilderImpl -> this.bindingHandler
+        is SingleLayerPlotBuilder -> this.bindingHandler
     }
 
 @PublishedApi
 internal val PlotBuilder.datasetBuilder: DatasetBuilder
     get() = when (this) {
-        is MultiLayerPlotBuilder -> datasetBuilder
-        is CustomPlotBuilder -> datasetBuilder
+        is MultiLayerPlotBuilder -> this.datasetBuilder
+        is CustomPlotBuilder -> this.datasetBuilder
     }
 
 @PublishedApi
 internal val PlotBuilder.plotFeatures: MutableMap<FeatureName, PlotFeature>
     get() = when (this) {
-        is MultiLayerPlotBuilder -> plotFeatures
-        is CustomPlotBuilder -> plotFeatures
+        is MultiLayerPlotBuilder -> this.plotFeatures
+        is CustomPlotBuilder -> this.plotFeatures
     }
 
 @PublishedApi
 internal val PlotBuilder.bindingHandler: BindingHandler
     get() = when (this) {
-        is MultiLayerPlotBuilder -> bindingHandler
-        is CustomPlotBuilder -> bindingHandler
+        is MultiLayerPlotBuilder -> this.bindingHandler
+        is CustomPlotBuilder -> this.bindingHandler
     }
 
diff --git a/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/DataFramePlotBuilder.kt b/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/DataFramePlotBuilder.kt
index 8b56b2cc2..6486bed98 100644
--- a/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/DataFramePlotBuilder.kt
+++ b/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/DataFramePlotBuilder.kt
@@ -91,7 +91,7 @@ public class DataFramePlotBuilder<T> @PublishedApi internal constructor(
 
     @PublishedApi
     internal fun addDataset(groupBy: GroupBy<*, *>): Int {
-        datasetBuilders.add(DatasetBuilderImpl.fromData(groupBy, datasetBuilder as DatasetBuilderImpl))
+        datasetBuilders.add(DatasetBuilderImpl(groupBy, datasetBuilder as DatasetBuilderImpl))
         return datasetBuilders.lastIndex
     }
 }
diff --git a/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/DataFrameSingleLayerPlotBuilder.kt b/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/DataFrameSingleLayerPlotBuilder.kt
index 3f055699d..93b3723bb 100644
--- a/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/DataFrameSingleLayerPlotBuilder.kt
+++ b/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/DataFrameSingleLayerPlotBuilder.kt
@@ -5,5 +5,5 @@ import org.jetbrains.kotlinx.kandy.ir.data.TableData
 
 public abstract class DataFrameSingleLayerPlotBuilder @PublishedApi internal constructor(data: TableData) :
     SingleLayerPlotBuilder() {
-    override val datasetBuilder = DatasetBuilderImpl.fromData(data)
+    override val datasetBuilder = DatasetBuilderImpl(data)
 }
diff --git a/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/DatasetBuilderImpl.kt b/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/DatasetBuilderImpl.kt
index fa161bd6b..d6ad53977 100644
--- a/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/DatasetBuilderImpl.kt
+++ b/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/DatasetBuilderImpl.kt
@@ -50,7 +50,7 @@ internal abstract class DatasetBuilderImpl(
         return when(column) {
             is ColumnAccessor<*> -> takeColumn(column)
             is DataColumn<*> -> addColumn(column)
-            else -> TODO()
+            else -> error("Unexpected column reference type: ${column::class}")
         }
     }
 
@@ -72,20 +72,20 @@ internal abstract class DatasetBuilderImpl(
         referredColumns[name] = columnId
         return columnId
     }
+}
 
-    internal companion object {
-        fun fromData(dataFrame: DataFrame<*>, initialBuilder: DatasetBuilderImpl? = null): NamedDataBuilder {
-            return NamedDataBuilder(dataFrame, initialBuilder)
-        }
-        fun fromData(groupBy: GroupBy<*, *>, initialBuilder: DatasetBuilderImpl? = null): GroupedDataBuilder {
-            return GroupedDataBuilder(groupBy, initialBuilder)
-        }
-        fun fromData(dataset: TableData, initialBuilder: DatasetBuilderImpl? = null): DatasetBuilderImpl {
-            return when (dataset) {
-                is NamedData -> NamedDataBuilder(dataset, initialBuilder)
-                is GroupedData ->GroupedDataBuilder(dataset, initialBuilder)
-                else -> error("Unexpected dataset type: ${dataset::class}")
-            }
-        }
+internal fun DatasetBuilderImpl(dataFrame: DataFrame<*>, initialBuilder: DatasetBuilderImpl? = null): NamedDataBuilder {
+    return NamedDataBuilder(dataFrame, initialBuilder)
+}
+
+internal fun DatasetBuilderImpl(groupBy: GroupBy<*, *>, initialBuilder: DatasetBuilderImpl? = null): GroupedDataBuilder {
+    return GroupedDataBuilder(groupBy, initialBuilder)
+}
+
+internal fun DatasetBuilderImpl(dataset: TableData, initialBuilder: DatasetBuilderImpl? = null): DatasetBuilderImpl {
+    return when (dataset) {
+        is NamedData -> NamedDataBuilder(dataset, initialBuilder)
+        is GroupedData ->GroupedDataBuilder(dataset, initialBuilder)
+        else -> error("Unexpected dataset type: ${dataset::class}")
     }
 }
diff --git a/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/GroupByPlotBuilder.kt b/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/GroupByPlotBuilder.kt
index 14f007357..ba8dee649 100644
--- a/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/GroupByPlotBuilder.kt
+++ b/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/GroupByPlotBuilder.kt
@@ -24,7 +24,7 @@ public class GroupByPlotBuilder<T, G> @PublishedApi internal constructor(
     internal val groupBy: GroupBy<T, G>,
     internal val dataframe: DataFrame<G> = groupBy.concatFixed()
 ) : MultiLayerPlotBuilderImpl(), ColumnsContainer<G> by dataframe, GroupedDataScope<T, G> {
-    override val datasetBuilders: MutableList<DatasetBuilder> = mutableListOf(DatasetBuilderImpl.fromData(groupBy))
+    override val datasetBuilders: MutableList<DatasetBuilder> = mutableListOf(DatasetBuilderImpl(groupBy))
 
     @Suppress("UNCHECKED_CAST")
     public override val key: ColumnGroup<T> =
diff --git a/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/MultiLayerPlotBuilderImpl.kt b/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/MultiLayerPlotBuilderImpl.kt
index 17eda9540..1259798da 100644
--- a/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/MultiLayerPlotBuilderImpl.kt
+++ b/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/MultiLayerPlotBuilderImpl.kt
@@ -7,7 +7,7 @@ import org.jetbrains.kotlinx.kandy.dsl.internal.MultiLayerPlotBuilder
 
 public abstract class MultiLayerPlotBuilderImpl: MultiLayerPlotBuilder() {
     override fun addDataset(dataset: TableData, initialBuilder: DatasetBuilder?): Int {
-        datasetBuilders.add(DatasetBuilderImpl.fromData(dataset, initialBuilder as DatasetBuilderImpl?))
+        datasetBuilders.add(DatasetBuilderImpl(dataset, initialBuilder as DatasetBuilderImpl?))
         return datasetBuilders.lastIndex
     }
 
diff --git a/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/accessors.kt b/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/accessors.kt
index f1ea898f6..16e2796b2 100644
--- a/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/accessors.kt
+++ b/kandy-api/src/main/kotlin/org/jetbrains/kotlinx/kandy/dsl/internal/dataframe/accessors.kt
@@ -3,6 +3,6 @@ package org.jetbrains.kotlinx.kandy.dsl.internal.dataframe
 @PublishedApi
 internal val GroupedDataScope<*, *>.datasetBuilder: DatasetBuilderImpl
     get() = when (this) {
-        is GroupByScope -> datasetBuilder as DatasetBuilderImpl
-        is GroupByPlotBuilder -> datasetBuilder as DatasetBuilderImpl
+        is GroupByScope -> this.datasetBuilder as DatasetBuilderImpl
+        is GroupByPlotBuilder -> this.datasetBuilder as DatasetBuilderImpl
     }
diff --git a/kandy-api/src/test/kotlin/org/jetbrains/kotlinx/kandy/builders/dataframe/datasetHandler.kt b/kandy-api/src/test/kotlin/org/jetbrains/kotlinx/kandy/builders/dataframe/datasetHandler.kt
index d32f0474d..0cd293037 100644
--- a/kandy-api/src/test/kotlin/org/jetbrains/kotlinx/kandy/builders/dataframe/datasetHandler.kt
+++ b/kandy-api/src/test/kotlin/org/jetbrains/kotlinx/kandy/builders/dataframe/datasetHandler.kt
@@ -31,19 +31,19 @@ class DatasetBuilderTest {
 
     @BeforeTest
     fun setup() {
-        handler = DatasetBuilderImpl.fromData(NamedData(dataFrame))
+        handler = DatasetBuilderImpl(NamedData(dataFrame))
 
         val groupedData = GroupedData(groupedDf)
         internalNumbers = groupedData.dataFrame["numbers"]
         internalType = groupedData.dataFrame["TYPE"]
         internalCond = groupedData.dataFrame["cond"]
-        handlerWithGrouped = DatasetBuilderImpl.fromData(groupedData)
+        handlerWithGrouped = DatasetBuilderImpl(groupedData)
     }
 
     @Test
     fun `test initial NamedData`() {
         val initialDataset = NamedData(emptyDataFrame<Any>())
-        val handler = DatasetBuilderImpl.fromData(initialDataset)
+        val handler = DatasetBuilderImpl(initialDataset)
 
         assertEquals(initialDataset.dataFrame, handler.baseDataFrame)
     }
@@ -61,7 +61,7 @@ class DatasetBuilderTest {
                 )
             ), listOf("column1")
         )
-        val handler = DatasetBuilderImpl.fromData(initialDataset)
+        val handler = DatasetBuilderImpl(initialDataset)
 
         assertEquals(initialDataset.dataFrame, handler.baseDataFrame)
     }
@@ -69,7 +69,7 @@ class DatasetBuilderTest {
     @Test
     fun `test add column with list values`() {
         val initialDataset = NamedData(emptyDataFrame<Any>())
-        val handler = DatasetBuilderImpl.fromData(initialDataset)
+        val handler = DatasetBuilderImpl(initialDataset)
         val values = listOf(1, 2, 3)
         val name = "new_column"
 
diff --git a/kandy-lets-plot/build.gradle.kts b/kandy-lets-plot/build.gradle.kts
index 14bf3d277..4c6b3aa5a 100644
--- a/kandy-lets-plot/build.gradle.kts
+++ b/kandy-lets-plot/build.gradle.kts
@@ -11,7 +11,6 @@ plugins {
 
 repositories {
     maven("https://packages.jetbrains.team/maven/p/kds/kotlin-ds-maven")
-    //mavenLocal()
 }
 
 dependencies {