diff --git a/kmath-functions/src/commonMain/kotlin/space/kscience/kmath/functions/listConstructors.kt b/kmath-functions/src/commonMain/kotlin/space/kscience/kmath/functions/listConstructors.kt
new file mode 100644
index 000000000..fc55ba310
--- /dev/null
+++ b/kmath-functions/src/commonMain/kotlin/space/kscience/kmath/functions/listConstructors.kt
@@ -0,0 +1,65 @@
+/*
+ * Copyright 2018-2021 KMath contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+/*
+ * Copyright 2018-2021 KMath contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package space.kscience.kmath.functions
+
+import space.kscience.kmath.operations.Ring
+
+
+/**
+ * Returns a [ListPolynomial] instance with given [coefficients]. The collection of coefficients will be reversed if
+ * [reverse] parameter is true.
+ */
+@Suppress("FunctionName")
+public fun <C> ListPolynomial(coefficients: List<C>, reverse: Boolean = false): ListPolynomial<C> =
+    ListPolynomial(with(coefficients) { if (reverse) reversed() else this })
+
+/**
+ * Returns a [ListPolynomial] instance with given [coefficients]. The collection of coefficients will be reversed if
+ * [reverse] parameter is true.
+ */
+@Suppress("FunctionName")
+public fun <C> ListPolynomial(vararg coefficients: C, reverse: Boolean = false): ListPolynomial<C> =
+    ListPolynomial(with(coefficients) { if (reverse) reversed() else toList() })
+
+public fun <C> C.asListPolynomial() : ListPolynomial<C> = ListPolynomial(listOf(this))
+
+
+// Waiting for context receivers :( FIXME: Replace with context receivers when they will be available
+
+@Suppress("FunctionName")
+public fun <C> ListRationalFunction(numeratorCoefficients: List<C>, denominatorCoefficients: List<C>, reverse: Boolean = false): ListRationalFunction<C> =
+    ListRationalFunction<C>(
+        ListPolynomial( with(numeratorCoefficients) { if (reverse) reversed() else this } ),
+        ListPolynomial( with(denominatorCoefficients) { if (reverse) reversed() else this } )
+    )
+@Suppress("FunctionName")
+public fun <C, A: Ring<C>> ListRationalFunctionSpace<C, A>.ListRationalFunction(numerator: ListPolynomial<C>): ListRationalFunction<C> =
+    ListRationalFunction<C>(numerator, polynomialOne)
+@Suppress("FunctionName")
+public fun <C, A: Ring<C>> A.ListRationalFunction(numerator: ListPolynomial<C>): ListRationalFunction<C> =
+    ListRationalFunction<C>(numerator, ListPolynomial(listOf(one)))
+@Suppress("FunctionName")
+public fun <C, A: Ring<C>> ListRationalFunctionSpace<C, A>.ListRationalFunction(numeratorCoefficients: List<C>, reverse: Boolean = false): ListRationalFunction<C> =
+    ListRationalFunction<C>(
+        ListPolynomial( with(numeratorCoefficients) { if (reverse) reversed() else this } ),
+        polynomialOne
+    )
+@Suppress("FunctionName")
+public fun <C, A: Ring<C>> A.ListRationalFunction(numeratorCoefficients: List<C>, reverse: Boolean = false): ListRationalFunction<C> =
+    ListRationalFunction<C>(
+        ListPolynomial( with(numeratorCoefficients) { if (reverse) reversed() else this } ),
+        ListPolynomial(listOf(one))
+    )
+
+//context(A)
+//public fun <C, A: Ring<C>> C.asListRationalFunction() : ListRationalFunction<C> = ListRationalFunction(asListPolynomial())
+//context(ListRationalFunctionSpace<C, A>)
+//public fun <C, A: Ring<C>> C.asListRationalFunction() : ListRationalFunction<C> = ListRationalFunction(asListPolynomial())
\ No newline at end of file
diff --git a/kmath-functions/src/commonTest/kotlin/space/kscience/kmath/test/misc/Rational.kt b/kmath-functions/src/commonTest/kotlin/space/kscience/kmath/test/misc/Rational.kt
new file mode 100644
index 000000000..72bb5942c
--- /dev/null
+++ b/kmath-functions/src/commonTest/kotlin/space/kscience/kmath/test/misc/Rational.kt
@@ -0,0 +1,135 @@
+/*
+ * Copyright 2018-2021 KMath contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package space.kscience.kmath.test.misc
+
+import space.kscience.kmath.misc.UnstableKMathAPI
+import space.kscience.kmath.operations.Field
+import space.kscience.kmath.operations.NumbersAddOps
+
+class Rational {
+    companion object {
+        val ZERO: Rational = Rational(0L)
+        val ONE: Rational = Rational(1L)
+    }
+
+    val numerator: Long
+    val denominator: Long
+
+    internal constructor(numerator: Long, denominator: Long, toCheckInput: Boolean = true) {
+        if (toCheckInput) {
+            if (denominator == 0L) throw ArithmeticException("/ by zero")
+
+            val greatestCommonDivider = gcd(numerator, denominator).let { if (denominator < 0L) -it else it }
+
+            this.numerator = numerator / greatestCommonDivider
+            this.denominator = denominator / greatestCommonDivider
+        } else {
+            this.numerator = numerator
+            this.denominator = denominator
+        }
+    }
+
+    constructor(numerator: Int, denominator: Int) : this(numerator.toLong(), denominator.toLong(), true)
+    constructor(numerator: Int, denominator: Long) : this(numerator.toLong(), denominator, true)
+    constructor(numerator: Long, denominator: Int) : this(numerator, denominator.toLong(), true)
+    constructor(numerator: Long, denominator: Long) : this(numerator, denominator, true)
+    constructor(numerator: Int) : this(numerator.toLong(), 1L, false)
+    constructor(numerator: Long) : this(numerator, 1L, false)
+
+    operator fun unaryPlus(): Rational = this
+    operator fun unaryMinus(): Rational = Rational(-this.numerator, this.denominator)
+    operator fun plus(other: Rational): Rational =
+        Rational(
+            numerator * other.denominator + denominator * other.numerator,
+            denominator * other.denominator
+        )
+    operator fun plus(other: Int): Rational =
+        Rational(
+            numerator + denominator * other.toLong(),
+            denominator
+        )
+    operator fun plus(other: Long): Rational =
+        Rational(
+            numerator + denominator * other,
+            denominator
+        )
+    operator fun minus(other: Rational): Rational =
+        Rational(
+            numerator * other.denominator - denominator * other.numerator,
+            denominator * other.denominator
+        )
+    operator fun minus(other: Int): Rational =
+        Rational(
+            numerator - denominator * other.toLong(),
+            denominator
+        )
+    operator fun minus(other: Long): Rational =
+        Rational(
+            numerator - denominator * other,
+            denominator
+        )
+    operator fun times(other: Rational): Rational =
+        Rational(
+            numerator * other.numerator,
+            denominator * other.denominator
+        )
+    operator fun times(other: Int): Rational =
+        Rational(
+            numerator * other.toLong(),
+            denominator
+        )
+    operator fun times(other: Long): Rational =
+        Rational(
+            numerator * other,
+            denominator
+        )
+    operator fun div(other: Rational): Rational =
+        Rational(
+            numerator * other.denominator,
+            denominator * other.numerator
+        )
+    operator fun div(other: Int): Rational =
+        Rational(
+            numerator,
+            denominator * other.toLong()
+        )
+    operator fun div(other: Long): Rational =
+        Rational(
+            numerator,
+            denominator * other
+        )
+    override fun equals(other: Any?): Boolean =
+        when (other) {
+            is Rational -> numerator == other.numerator && denominator == other.denominator
+            is Int -> numerator == other && denominator == 1L
+            is Long -> numerator == other && denominator == 1L
+            else -> false
+        }
+
+    override fun hashCode(): Int = 31 * numerator.hashCode() + denominator.hashCode()
+
+    override fun toString(): String = if (denominator == 1L) "$numerator" else "$numerator/$denominator"
+}
+
+@Suppress("EXTENSION_SHADOWED_BY_MEMBER", "OVERRIDE_BY_INLINE", "NOTHING_TO_INLINE")
+@OptIn(UnstableKMathAPI::class)
+object RationalField : Field<Rational>, NumbersAddOps<Rational> {
+    override inline val zero: Rational get() = Rational.ZERO
+    override inline val one: Rational get() = Rational.ONE
+
+    override inline fun number(value: Number): Rational = Rational(value.toLong())
+
+    override inline fun add(left: Rational, right: Rational): Rational = left + right
+    override inline fun multiply(left: Rational, right: Rational): Rational = left * right
+    override inline fun divide(left: Rational, right: Rational): Rational = left / right
+    override inline fun scale(a: Rational, value: Double): Rational = a * number(value)
+
+    override inline fun Rational.unaryMinus(): Rational = -this
+    override inline fun Rational.plus(arg: Rational): Rational = this + arg
+    override inline fun Rational.minus(arg: Rational): Rational = this - arg
+    override inline fun Rational.times(arg: Rational): Rational = this * arg
+    override inline fun Rational.div(arg: Rational): Rational = this / arg
+}
\ No newline at end of file