diff --git a/runtime/src/main/kotlin/kotlin/annotations.kt b/runtime/src/main/kotlin/kotlin/Annotations.kt
similarity index 82%
rename from runtime/src/main/kotlin/kotlin/annotations.kt
rename to runtime/src/main/kotlin/kotlin/Annotations.kt
index aea14403a09..550c9b64a61 100644
--- a/runtime/src/main/kotlin/kotlin/annotations.kt
+++ b/runtime/src/main/kotlin/kotlin/Annotations.kt
@@ -26,4 +26,12 @@ annotation class ExportTypeInfo(val name: String)
 //@Target(CLASS, ANNOTATION_CLASS, PROPERTY, FIELD, LOCAL_VARIABLE, VALUE_PARAMETER,
 //        CONSTRUCTOR, FUNCTION, PROPERTY_GETTER, PROPERTY_SETTER, TYPE, EXPRESSION, FILE, TYPEALIAS)
 //@Retention(SOURCE)
-public annotation class Suppress(vararg val names: String)
\ No newline at end of file
+public annotation class Suppress(vararg val names: String)
+
+/**
+ * Suppresses errors about variance conflict
+ */
+@Target(AnnotationTarget.TYPE)
+//@Retention(SOURCE)
+//@MustBeDocumented
+public annotation class UnsafeVariance
\ No newline at end of file
diff --git a/runtime/src/main/kotlin/kotlin/collections/AbstractCollection.kt b/runtime/src/main/kotlin/kotlin/collections/AbstractCollection.kt
new file mode 100644
index 00000000000..1d9b66e466d
--- /dev/null
+++ b/runtime/src/main/kotlin/kotlin/collections/AbstractCollection.kt
@@ -0,0 +1,19 @@
+package kotlin.collections
+
+public abstract class AbstractCollection<out E> protected constructor() : Collection<E> {
+    abstract override val size: Int
+    abstract override fun iterator(): Iterator<E>
+
+    /* TODO: uncomment, once can support lambdas.
+    override fun contains(element: @UnsafeVariance E): Boolean = any { it == element }
+
+    override fun containsAll(elements: Collection<@UnsafeVariance E>): Boolean =
+            elements.all { contains(it) }
+
+    override fun isEmpty(): Boolean = size == 0
+
+    override fun toString(): String = joinToString(", ", "[", "]") {
+        if (it === this) "(this Collection)" else it.toString()
+    } */
+
+}
diff --git a/runtime/src/main/kotlin/kotlin/collections/Collection.kt b/runtime/src/main/kotlin/kotlin/collections/Collection.kt
new file mode 100644
index 00000000000..bfdf0dbbd1c
--- /dev/null
+++ b/runtime/src/main/kotlin/kotlin/collections/Collection.kt
@@ -0,0 +1,83 @@
+package kotlin.collections
+
+/**
+ * A generic collection of elements. Methods in this interface support only read-only access to the collection;
+ * read/write access is supported through the [MutableCollection] interface.
+ * @param E the type of elements contained in the collection.
+ */
+public interface Collection<out E> : Iterable<E> {
+    // Query Operations
+    /**
+     * Returns the size of the collection.
+     */
+    public val size: Int
+
+    /**
+     * Returns `true` if the collection is empty (contains no elements), `false` otherwise.
+     */
+    public fun isEmpty(): Boolean
+
+    /**
+     * Checks if the specified element is contained in this collection.
+     */
+    public operator fun contains(element: @UnsafeVariance E): Boolean
+    override fun iterator(): Iterator<E>
+
+    // Bulk Operations
+    /**
+     * Checks if all elements in the specified collection are contained in this collection.
+     */
+    public fun containsAll(elements: Collection<@UnsafeVariance E>): Boolean
+}
+
+/**
+ * A generic collection of elements that supports adding and removing elements.
+ */
+public interface MutableCollection<E> : Collection<E>, MutableIterable<E> {
+    // Query Operations
+    override fun iterator(): MutableIterator<E>
+
+    // Modification Operations
+    /**
+     * Adds the specified element to the collection.
+     *
+     * @return `true` if the element has been added, `false` if the collection does not support duplicates
+     * and the element is already contained in the collection.
+     */
+    public fun add(element: E): Boolean
+
+    /**
+     * Removes a single instance of the specified element from this
+     * collection, if it is present.
+     *
+     * @return `true` if the element has been successfully removed; `false` if it was not present in the collection.
+     */
+    public fun remove(element: E): Boolean
+
+    // Bulk Modification Operations
+    /**
+     * Adds all of the elements in the specified collection to this collection.
+     *
+     * @return `true` if any of the specified elements was added to the collection, `false` if the collection was not modified.
+     */
+    public fun addAll(elements: Collection<E>): Boolean
+
+    /**
+     * Removes all of this collection's elements that are also contained in the specified collection.
+     *
+     * @return `true` if any of the specified elements was removed from the collection, `false` if the collection was not modified.
+     */
+    public fun removeAll(elements: Collection<E>): Boolean
+
+    /**
+     * Retains only the elements in this collection that are contained in the specified collection.
+     *
+     * @return `true` if any element was removed from the collection, `false` if the collection was not modified.
+     */
+    public fun retainAll(elements: Collection<E>): Boolean
+
+    /**
+     * Removes all elements from this collection.
+     */
+    public fun clear(): Unit
+}
diff --git a/runtime/src/main/kotlin/kotlin/collections/List.kt b/runtime/src/main/kotlin/kotlin/collections/List.kt
new file mode 100644
index 00000000000..9b937282367
--- /dev/null
+++ b/runtime/src/main/kotlin/kotlin/collections/List.kt
@@ -0,0 +1,104 @@
+package kotlin.collections
+
+/**
+* A generic ordered collection of elements. Methods in this interface support only read-only access to the list;
+* read/write access is supported through the [MutableList] interface.
+* @param E the type of elements contained in the list.
+*/
+public interface List<out E> : Collection<E> {
+    // Query Operations
+    override val size: Int
+    override fun isEmpty(): Boolean
+    override fun contains(element: @UnsafeVariance E): Boolean
+    override fun iterator(): Iterator<E>
+
+    // Bulk Operations
+    override fun containsAll(elements: Collection<@UnsafeVariance E>): Boolean
+
+    // Positional Access Operations
+    /**
+     * Returns the element at the specified index in the list.
+     */
+    public operator fun get(index: Int): E
+
+    // Search Operations
+    /**
+     * Returns the index of the first occurrence of the specified element in the list, or -1 if the specified
+     * element is not contained in the list.
+     */
+    public fun indexOf(element: @UnsafeVariance E): Int
+
+    /**
+     * Returns the index of the last occurrence of the specified element in the list, or -1 if the specified
+     * element is not contained in the list.
+     */
+    public fun lastIndexOf(element: @UnsafeVariance E): Int
+
+    // List Iterators
+    /**
+     * Returns a list iterator over the elements in this list (in proper sequence).
+     */
+    public fun listIterator(): ListIterator<E>
+
+    /**
+     * Returns a list iterator over the elements in this list (in proper sequence), starting at the specified [index].
+     */
+    public fun listIterator(index: Int): ListIterator<E>
+
+    // View
+    /**
+     * Returns a view of the portion of this list between the specified [fromIndex] (inclusive) and [toIndex] (exclusive).
+     * The returned list is backed by this list, so non-structural changes in the returned list are reflected in this list, and vice-versa.
+     */
+    public fun subList(fromIndex: Int, toIndex: Int): List<E>
+}
+
+/**
+ * A generic ordered collection of elements that supports adding and removing elements.
+ * @param E the type of elements contained in the list.
+ */
+public interface MutableList<E> : List<E>, MutableCollection<E> {
+    // Modification Operations
+    override fun add(element: E): Boolean
+    override fun remove(element: E): Boolean
+
+    // Bulk Modification Operations
+    override fun addAll(elements: Collection<E>): Boolean
+
+    /**
+     * Inserts all of the elements in the specified collection [elements] into this list at the specified [index].
+     *
+     * @return `true` if the list was changed as the result of the operation.
+     */
+    public fun addAll(index: Int, elements: Collection<E>): Boolean
+    override fun removeAll(elements: Collection<E>): Boolean
+    override fun retainAll(elements: Collection<E>): Boolean
+    override fun clear(): Unit
+
+    // Positional Access Operations
+    /**
+     * Replaces the element at the specified position in this list with the specified element.
+     *
+     * @return the element previously at the specified position.
+     */
+    public operator fun set(index: Int, element: E): E
+
+    /**
+     * Inserts an element into the list at the specified [index].
+     */
+    public fun add(index: Int, element: E): Unit
+
+    /**
+     * Removes an element at the specified [index] from the list.
+     *
+     * @return the element that has been removed.
+     */
+    public fun removeAt(index: Int): E
+
+    // List Iterators
+    override fun listIterator(): MutableListIterator<E>
+    override fun listIterator(index: Int): MutableListIterator<E>
+
+    // View
+    override fun subList(fromIndex: Int, toIndex: Int): MutableList<E>
+}
\ No newline at end of file
diff --git a/runtime/src/main/kotlin/kotlin/collections/Map.kt b/runtime/src/main/kotlin/kotlin/collections/Map.kt
new file mode 100644
index 00000000000..e0eae733950
--- /dev/null
+++ b/runtime/src/main/kotlin/kotlin/collections/Map.kt
@@ -0,0 +1,133 @@
+package kotlin.collections
+
+/**
+ * A collection that holds pairs of objects (keys and values) and supports efficiently retrieving
+ * the value corresponding to each key. Map keys are unique; the map holds only one value for each key.
+ * Methods in this interface support only read-only access to the map; read-write access is supported through
+ * the [MutableMap] interface.
+ * @param K the type of map keys.
+ * @param V the type of map values.
+ */
+public interface Map<K, out V> {
+    // Query Operations
+    /**
+     * Returns the number of key/value pairs in the map.
+     */
+    public val size: Int
+
+    /**
+     * Returns `true` if the map is empty (contains no elements), `false` otherwise.
+     */
+    public fun isEmpty(): Boolean
+
+    /**
+     * Returns `true` if the map contains the specified [key].
+     */
+    public fun containsKey(key: K): Boolean
+
+    /**
+     * Returns `true` if the map maps one or more keys to the specified [value].
+     */
+    public fun containsValue(value: @UnsafeVariance V): Boolean
+
+    /**
+     * Returns the value corresponding to the given [key], or `null` if such a key is not present in the map.
+     */
+    public operator fun get(key: K): V?
+
+    /**
+     * Returns the value corresponding to the given [key], or [defaultValue] if such a key is not present in the map.
+     *
+     * @since JDK 1.8
+     */
+    public fun getOrDefault(key: K, defaultValue: @UnsafeVariance V): V
+
+    // Views
+    /**
+     * Returns a [Set] of all keys in this map.
+     */
+    public val keys: Set<K>
+
+    /**
+     * Returns a [Collection] of all values in this map. Note that this collection may contain duplicate values.
+     */
+    public val values: Collection<V>
+
+    /**
+     * Returns a [Set] of all key/value pairs in this map.
+     */
+    public val entries: Set<Map.Entry<K, V>>
+
+    /**
+     * Represents a key/value pair held by a [Map].
+     */
+    public interface Entry<out K, out V> {
+        /**
+         * Returns the key of this key/value pair.
+         */
+        public val key: K
+
+        /**
+         * Returns the value of this key/value pair.
+         */
+        public val value: V
+    }
+}
+
+/**
+ * A modifiable collection that holds pairs of objects (keys and values) and supports efficiently retrieving
+ * the value corresponding to each key. Map keys are unique; the map holds only one value for each key.
+ * @param K the type of map keys.
+ * @param V the type of map values.
+ */
+public interface MutableMap<K, V> : Map<K, V> {
+    // Modification Operations
+    /**
+     * Associates the specified [value] with the specified [key] in the map.
+     *
+     * @return the previous value associated with the key, or `null` if the key was not present in the map.
+     */
+    public fun put(key: K, value: V): V?
+
+    /**
+     * Removes the specified key and its corresponding value from this map.
+     *
+     * @return the previous value associated with the key, or `null` if the key was not present in the map.
+     */
+    public fun remove(key: K): V?
+
+    /**
+     * Removes the entry for the specified key only if it is mapped to the specified value.
+     *
+     * @return true if entry was removed
+     */
+    public fun remove(key: K, value: V): Boolean
+
+    // Bulk Modification Operations
+    /**
+     * Updates this map with key/value pairs from the specified map [from].
+     */
+    public fun putAll(from: Map<out K, V>): Unit
+
+    /**
+     * Removes all elements from this map.
+     */
+    public fun clear(): Unit
+
+    // Views
+    override val keys: MutableSet<K>
+    override val values: MutableCollection<V>
+    override val entries: MutableSet<MutableMap.MutableEntry<K, V>>
+
+    /**
+     * Represents a key/value pair held by a [MutableMap].
+     */
+    public interface MutableEntry<K,V>: Map.Entry<K, V> {
+        /**
+         * Changes the value associated with the key of this entry.
+         *
+         * @return the previous value corresponding to the key.
+         */
+        public fun setValue(newValue: V): V
+    }
+}
diff --git a/runtime/src/main/kotlin/kotlin/collections/ReversedViews.kt b/runtime/src/main/kotlin/kotlin/collections/ReversedViews.kt
new file mode 100644
index 00000000000..87eb9eb9d96
--- /dev/null
+++ b/runtime/src/main/kotlin/kotlin/collections/ReversedViews.kt
@@ -0,0 +1,39 @@
+package kotlin.collections
+/*
+private open class ReversedListReadOnly<out T>(private val delegate: List<T>) : AbstractList<T>() {
+    override val size: Int get() = delegate.size
+    override fun get(index: Int): T = delegate[reverseElementIndex(index)]
+
+}
+
+private class ReversedList<T>(private val delegate: MutableList<T>) : AbstractMutableList<T>() {
+    override val size: Int get() = delegate.size
+    override fun get(index: Int): T = delegate[reverseElementIndex(index)]
+
+    override fun clear() = delegate.clear()
+    override fun removeAt(index: Int): T = delegate.removeAt(reverseElementIndex(index))
+
+    override fun set(index: Int, element: T): T = delegate.set(reverseElementIndex(index), element)
+    override fun add(index: Int, element: T) {
+        delegate.add(reversePositionIndex(index), element)
+    }
+}
+private fun List<*>.reverseElementIndex(index: Int) = // TODO: Use AbstractList.checkElementIndex: run { AbstractList.checkElementIndex(index, size); lastIndex - index }
+        if (index in 0..size - 1) size - index - 1 else throw IndexOutOfBoundsException("Index $index should be in range [${0..size - 1}].")
+
+private fun List<*>.reversePositionIndex(index: Int) =
+        if (index in 0..size) size - index else throw IndexOutOfBoundsException("Index $index should be in range [${0..size}].")
+
+
+/**
+ * Returns a reversed read-only view of the original List.
+ * All changes made in the original list will be reflected in the reversed one.
+ */
+public fun <T> List<T>.asReversed(): List<T> = ReversedListReadOnly(this)
+
+/**
+ * Returns a reversed mutable view of the original mutable List.
+ * All changes made in the original list will be reflected in the reversed one and vice versa.
+ */
+public fun <T> MutableList<T>.asReversed(): MutableList<T> = ReversedList(this)
+*/
\ No newline at end of file
diff --git a/runtime/src/main/kotlin/kotlin/collections/Set.kt b/runtime/src/main/kotlin/kotlin/collections/Set.kt
new file mode 100644
index 00000000000..1073b69e8a7
--- /dev/null
+++ b/runtime/src/main/kotlin/kotlin/collections/Set.kt
@@ -0,0 +1,38 @@
+package kotlin.collections
+
+/**
+ * A generic unordered collection of elements that does not support duplicate elements.
+ * Methods in this interface support only read-only access to the set;
+ * read/write access is supported through the [MutableSet] interface.
+ * @param E the type of elements contained in the set.
+ */
+public interface Set<out E> : Collection<E> {
+    // Query Operations
+    override val size: Int
+    override fun isEmpty(): Boolean
+    override fun contains(element: @UnsafeVariance E): Boolean
+    override fun iterator(): Iterator<E>
+
+    // Bulk Operations
+    override fun containsAll(elements: Collection<@UnsafeVariance E>): Boolean
+}
+
+/**
+ * A generic unordered collection of elements that does not support duplicate elements, and supports
+ * adding and removing elements.
+ * @param E the type of elements contained in the set.
+ */
+public interface MutableSet<E> : Set<E>, MutableCollection<E> {
+    // Query Operations
+    override fun iterator(): MutableIterator<E>
+
+    // Modification Operations
+    override fun add(element: E): Boolean
+    override fun remove(element: E): Boolean
+
+    // Bulk Modification Operations
+    override fun addAll(elements: Collection<E>): Boolean
+    override fun removeAll(elements: Collection<E>): Boolean
+    override fun retainAll(elements: Collection<E>): Boolean
+    override fun clear(): Unit
+}