diff --git a/compiler/testData/codegen/box/builderInference/issues/kt47989a.kt b/compiler/testData/codegen/box/builderInference/issues/kt47989a.kt
new file mode 100644
index 00000000000..c4650b3fb71
--- /dev/null
+++ b/compiler/testData/codegen/box/builderInference/issues/kt47989a.kt
@@ -0,0 +1,32 @@
+// ISSUE: KT-47989
+
+// IGNORE_LIGHT_ANALYSIS
+// IGNORE_BACKEND: ANY
+// REASON: red code (see corresponding diagnostic test)
+
+fun box(): String {
+    build {
+        object: TypeSourceInterface {
+            override fun produceTargetType() = getTypeVariable()
+        }
+    }
+    return "OK"
+}
+
+
+
+
+class TargetType
+
+interface TypeSourceInterface {
+    fun produceTargetType(): TargetType
+}
+
+class Buildee<TV> {
+    fun getTypeVariable(): TV = storage
+    private var storage: TV = TargetType() as TV
+}
+
+fun <PTV> build(instructions: Buildee<PTV>.() -> Unit): Buildee<PTV> {
+    return Buildee<PTV>().apply(instructions)
+}
diff --git a/compiler/testData/codegen/box/builderInference/issues/kt47989b.kt b/compiler/testData/codegen/box/builderInference/issues/kt47989b.kt
new file mode 100644
index 00000000000..1378ff24463
--- /dev/null
+++ b/compiler/testData/codegen/box/builderInference/issues/kt47989b.kt
@@ -0,0 +1,29 @@
+// ISSUE: KT-47989
+
+// IGNORE_LIGHT_ANALYSIS
+// IGNORE_BACKEND: ANY
+// REASON: red code (see corresponding diagnostic test)
+
+fun box(): String {
+    build {
+        object: TypeSourceInterface {
+            override fun produceTargetTypeBuildee() = this@build
+        }
+    }
+    return "OK"
+}
+
+
+
+
+class TargetType
+
+interface TypeSourceInterface {
+    fun produceTargetTypeBuildee(): Buildee<TargetType>
+}
+
+class Buildee<TV>
+
+fun <PTV> build(instructions: Buildee<PTV>.() -> Unit): Buildee<PTV> {
+    return Buildee<PTV>().apply(instructions)
+}
diff --git a/compiler/testData/diagnostics/tests/builderInference/issues/kt47989a.fir.kt b/compiler/testData/diagnostics/tests/builderInference/issues/kt47989a.fir.kt
new file mode 100644
index 00000000000..1a8490741a7
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/builderInference/issues/kt47989a.fir.kt
@@ -0,0 +1,31 @@
+// ISSUE: KT-47989
+// CHECK_TYPE_WITH_EXACT
+
+fun test() {
+    val buildee = <!NEW_INFERENCE_NO_INFORMATION_FOR_PARAMETER!>build<!> {
+        object: TypeSourceInterface {
+            override fun produceTargetType() = getTypeVariable()
+        }
+    }
+    // exact type equality check — turns unexpected compile-time behavior into red code
+    // considered to be non-user-reproducible code for the purposes of these tests
+    <!NEW_INFERENCE_NO_INFORMATION_FOR_PARAMETER!>checkExactType<!><<!CANNOT_INFER_PARAMETER_TYPE!>Buildee<TargetType><!>>(buildee)
+}
+
+
+
+
+class TargetType
+
+interface TypeSourceInterface {
+    fun produceTargetType(): TargetType
+}
+
+class Buildee<TV> {
+    fun getTypeVariable(): TV = storage
+    private var storage: TV = null!!
+}
+
+fun <PTV> build(instructions: Buildee<PTV>.() -> Unit): Buildee<PTV> {
+    return Buildee<PTV>().apply(instructions)
+}
diff --git a/compiler/testData/diagnostics/tests/builderInference/issues/kt47989a.kt b/compiler/testData/diagnostics/tests/builderInference/issues/kt47989a.kt
new file mode 100644
index 00000000000..b143b6f562c
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/builderInference/issues/kt47989a.kt
@@ -0,0 +1,31 @@
+// ISSUE: KT-47989
+// CHECK_TYPE_WITH_EXACT
+
+fun test() {
+    val buildee = <!NEW_INFERENCE_NO_INFORMATION_FOR_PARAMETER!>build<!> {
+        object: TypeSourceInterface {
+            override fun produceTargetType() = getTypeVariable()
+        }
+    }
+    // exact type equality check — turns unexpected compile-time behavior into red code
+    // considered to be non-user-reproducible code for the purposes of these tests
+    checkExactType<Buildee<TargetType>>(<!DEBUG_INFO_ELEMENT_WITH_ERROR_TYPE!>buildee<!>)
+}
+
+
+
+
+class TargetType
+
+interface TypeSourceInterface {
+    fun produceTargetType(): TargetType
+}
+
+class Buildee<TV> {
+    fun getTypeVariable(): TV = storage
+    private var storage: TV = null!!
+}
+
+fun <PTV> build(instructions: Buildee<PTV>.() -> Unit): Buildee<PTV> {
+    return Buildee<PTV>().apply(instructions)
+}
diff --git a/compiler/testData/diagnostics/tests/builderInference/issues/kt47989b.fir.kt b/compiler/testData/diagnostics/tests/builderInference/issues/kt47989b.fir.kt
new file mode 100644
index 00000000000..d295ffdee9b
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/builderInference/issues/kt47989b.fir.kt
@@ -0,0 +1,28 @@
+// ISSUE: KT-47989
+// CHECK_TYPE_WITH_EXACT
+
+fun test() {
+    val buildee = <!NEW_INFERENCE_NO_INFORMATION_FOR_PARAMETER!>build<!> {
+        object: TypeSourceInterface {
+            override fun <!RETURN_TYPE_MISMATCH_ON_OVERRIDE!>produceTargetTypeBuildee<!>() = this@build
+        }
+    }
+    // exact type equality check — turns unexpected compile-time behavior into red code
+    // considered to be non-user-reproducible code for the purposes of these tests
+    <!NEW_INFERENCE_NO_INFORMATION_FOR_PARAMETER!>checkExactType<!><<!CANNOT_INFER_PARAMETER_TYPE!>Buildee<TargetType><!>>(buildee)
+}
+
+
+
+
+class TargetType
+
+interface TypeSourceInterface {
+    fun produceTargetTypeBuildee(): Buildee<TargetType>
+}
+
+class Buildee<TV>
+
+fun <PTV> build(instructions: Buildee<PTV>.() -> Unit): Buildee<PTV> {
+    return Buildee<PTV>().apply(instructions)
+}
diff --git a/compiler/testData/diagnostics/tests/builderInference/issues/kt47989b.kt b/compiler/testData/diagnostics/tests/builderInference/issues/kt47989b.kt
new file mode 100644
index 00000000000..907c9a3795d
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/builderInference/issues/kt47989b.kt
@@ -0,0 +1,28 @@
+// ISSUE: KT-47989
+// CHECK_TYPE_WITH_EXACT
+
+fun test() {
+    val buildee = <!NEW_INFERENCE_NO_INFORMATION_FOR_PARAMETER!>build<!> {
+        object: TypeSourceInterface {
+            override fun produceTargetTypeBuildee() = this@build
+        }
+    }
+    // exact type equality check — turns unexpected compile-time behavior into red code
+    // considered to be non-user-reproducible code for the purposes of these tests
+    checkExactType<Buildee<TargetType>>(<!DEBUG_INFO_ELEMENT_WITH_ERROR_TYPE!>buildee<!>)
+}
+
+
+
+
+class TargetType
+
+interface TypeSourceInterface {
+    fun produceTargetTypeBuildee(): Buildee<TargetType>
+}
+
+class Buildee<TV>
+
+fun <PTV> build(instructions: Buildee<PTV>.() -> Unit): Buildee<PTV> {
+    return Buildee<PTV>().apply(instructions)
+}