diff --git a/ets2panda/checker/ETSchecker.cpp b/ets2panda/checker/ETSchecker.cpp
index eed861a87bb438abd614d1b709e6002069cf14f1..f9e052f39f937fd28397b1efeaa18d1da1f25fa1 100644
--- a/ets2panda/checker/ETSchecker.cpp
+++ b/ets2panda/checker/ETSchecker.cpp
@@ -426,7 +426,7 @@ bool ETSChecker::IsClassStaticMethod(checker::ETSObjectType *objType, checker::S
 
     // Bugs: these types do not appear as a valid TypeKind, as the TypeKind has more then one bit set
     [[maybe_unused]] static constexpr auto NOT_A_TYPE_KIND = TypeFlag::ETS_DYNAMIC_FLAG;
-
+    CHECK_NOT_NULL(type);
     auto res = static_cast<checker::TypeFlag>(type->TypeFlags() & ~(TO_CLEAR));
     ES2PANDA_ASSERT_POS(res == TypeFlag::NONE || helpers::math::IsPowerOfTwo(res & ~(NOT_A_TYPE_KIND)),
                         ark::es2panda::GetPositionForDiagnostic());
diff --git a/ets2panda/checker/types/ets/etsAnyType.cpp b/ets2panda/checker/types/ets/etsAnyType.cpp
index 811705455b8d6f9b88ff1d5b3624ce67a0aa2d46..63dc4d14176068f7a18e0ad929ab48a862765001 100644
--- a/ets2panda/checker/types/ets/etsAnyType.cpp
+++ b/ets2panda/checker/types/ets/etsAnyType.cpp
@@ -64,6 +64,7 @@ void ETSAnyType::Cast(TypeRelation *relation, Type *target)
 
     if (relation->ApplyUnboxing()) {
         auto *const boxedTarget = relation->GetChecker()->AsETSChecker()->MaybeBoxInRelation(target);
+        ES2PANDA_ASSERT(boxedTarget != nullptr);
         conversion::Unboxing(relation, boxedTarget->AsETSObjectType());
         relation->Result(true);
     }
diff --git a/ets2panda/compiler/core/ETSGen.cpp b/ets2panda/compiler/core/ETSGen.cpp
index bd7cb0bcbe58efbaff92b1678f72441a5e94fce2..040790ec1bbe6291835f0531d64e083dda06ee76 100644
--- a/ets2panda/compiler/core/ETSGen.cpp
+++ b/ets2panda/compiler/core/ETSGen.cpp
@@ -788,6 +788,7 @@ void ETSGen::IsInstanceDynamic(const ir::BinaryExpression *const node, const VRe
 void ETSGen::TestIsInstanceConstituent(const ir::AstNode *const node, std::tuple<Label *, Label *> label,
                                        checker::Type const *target, bool acceptNull)
 {
+    ES2PANDA_ASSERT(target != nullptr);
     ES2PANDA_ASSERT(!target->IsETSDynamicType());
     auto [ifTrue, ifFalse] = label;
 
@@ -859,6 +860,7 @@ void ETSGen::BranchIfIsInstance(const ir::AstNode *const node, const VReg srcReg
 void ETSGen::IsInstance(const ir::AstNode *const node, const VReg srcReg, const checker::Type *target)
 {
     target = Checker()->GetApparentType(target);
+    ES2PANDA_ASSERT(target != nullptr);
     ES2PANDA_ASSERT(target->IsETSReferenceType() && GetAccumulatorType() != nullptr);
 
     if (target->IsETSAnyType()) {  // should be IsSupertypeOf(target, source)
@@ -886,6 +888,7 @@ void ETSGen::IsInstance(const ir::AstNode *const node, const VReg srcReg, const
 // isinstance can only be used for Object and [] types, ensure source is not null!
 void ETSGen::InternalIsInstance(const ir::AstNode *node, const es2panda::checker::Type *target)
 {
+    ES2PANDA_ASSERT(target != nullptr);
     ES2PANDA_ASSERT(target->IsETSObjectType() || target->IsETSArrayType());
     if (!IsNullUnsafeObjectType(target)) {
         EmitIsInstance(node, ToAssemblerType(target));
@@ -898,6 +901,7 @@ void ETSGen::InternalIsInstance(const ir::AstNode *node, const es2panda::checker
 // checkcast can only be used for Object and [] types, ensure source is not nullish!
 void ETSGen::InternalCheckCast(const ir::AstNode *node, const es2panda::checker::Type *target)
 {
+    ES2PANDA_ASSERT(target != nullptr);
     ES2PANDA_ASSERT(target->IsETSObjectType() || target->IsETSArrayType() || target->IsETSTupleType());
     if (!IsNullUnsafeObjectType(target)) {
         EmitCheckCast(node, ToAssemblerType(target));
@@ -908,6 +912,7 @@ void ETSGen::InternalCheckCast(const ir::AstNode *node, const es2panda::checker:
 // optimized specialization for object and [] targets
 void ETSGen::CheckedReferenceNarrowingObject(const ir::AstNode *node, const checker::Type *target)
 {
+    ES2PANDA_ASSERT(target != nullptr);
     ES2PANDA_ASSERT(target->IsETSObjectType() || target->IsETSArrayType() || target->IsETSTupleType());
     const RegScope rs(this);
     const auto srcReg = AllocReg();
@@ -946,6 +951,7 @@ void ETSGen::CheckedReferenceNarrowingObject(const ir::AstNode *node, const chec
 // Implemented on top of the runtime type system, do not relax checks, do not introduce new types
 void ETSGen::CheckedReferenceNarrowing(const ir::AstNode *node, const checker::Type *target)
 {
+    ES2PANDA_ASSERT(target != nullptr);
     // NOTE(vpukhov): #19701 void refactoring
     if (target->IsETSVoidType()) {
         SetAccumulatorType(target);
@@ -953,8 +959,8 @@ void ETSGen::CheckedReferenceNarrowing(const ir::AstNode *node, const checker::T
     }
 
     target = Checker()->GetApparentType(target);
+    ES2PANDA_ASSERT(target != nullptr);
     ES2PANDA_ASSERT(target->IsETSReferenceType());
-
     if (target->IsETSAnyType()) {  // should be IsSupertypeOf(target, source)
         SetAccumulatorType(target);
         return;
@@ -1050,6 +1056,7 @@ void ETSGen::ApplyConversionCast(const ir::AstNode *node, const checker::Type *t
         case checker::TypeFlag::ETS_ARRAY:
         case checker::TypeFlag::ETS_OBJECT:
         case checker::TypeFlag::ETS_TYPE_PARAMETER: {
+            ES2PANDA_ASSERT(GetAccumulatorType() != nullptr);
             if (GetAccumulatorType() != nullptr && GetAccumulatorType()->IsETSDynamicType()) {
                 CastDynamicToObject(node, targetType);
             }
@@ -1676,6 +1683,7 @@ void ETSGen::CastToInt(const ir::AstNode *node)
 
 void ETSGen::CastToReftype(const ir::AstNode *const node, const checker::Type *const targetType, const bool unchecked)
 {
+    ES2PANDA_ASSERT(GetAccumulatorType() != nullptr);
     ES2PANDA_ASSERT(GetAccumulatorType()->IsETSReferenceType());
 
     const auto *const sourceType = GetAccumulatorType();
@@ -1741,6 +1749,7 @@ void ETSGen::CastDynamicToObject(const ir::AstNode *node, const checker::Type *t
     if (targetType->IsETSArrayType() || targetType->IsETSObjectType() || targetType->IsETSTypeParameter() ||
         targetType->IsETSUnionType() || targetType->IsETSFunctionType() || targetType->DefinitelyETSNullish() ||
         targetType->IsETSTupleType() || targetType->IsETSAnyType()) {
+        ES2PANDA_ASSERT(GetAccumulatorType() != nullptr);
         auto lang = GetAccumulatorType()->AsETSDynamicType()->Language();
         auto methodName = compiler::Signatures::Dynamic::GetObjectBuiltin(lang);
 
@@ -1809,6 +1818,7 @@ void ETSGen::CastToDynamic(const ir::AstNode *node, const checker::ETSDynamicTyp
             }
             [[fallthrough]];
         case checker::TypeFlag::FUNCTION:
+            ES2PANDA_ASSERT(GetAccumulatorType() != nullptr);
             ES2PANDA_ASSERT(!GetAccumulatorType()->IsETSMethodType());
             [[fallthrough]];
         case checker::TypeFlag::ETS_ARRAY: