diff --git a/codon/parser/cache.h b/codon/parser/cache.h
index 7adcb4c8..63f7161f 100644
--- a/codon/parser/cache.h
+++ b/codon/parser/cache.h
@@ -133,6 +133,9 @@ struct Cache : public std::enable_shared_from_this<Cache> {
     /// Realization lookup table that maps a realized class name to the corresponding
     /// ClassRealization instance.
     std::unordered_map<std::string, std::shared_ptr<ClassRealization>> realizations;
+    /// List of inherited class. We also keep the number of fields each of inherited
+    /// class.
+    std::vector<std::pair<std::string, int>> parentClasses;
 
     Class() : ast(nullptr), originalAst(nullptr) {}
   };
diff --git a/codon/parser/visitors/simplify/simplify.cpp b/codon/parser/visitors/simplify/simplify.cpp
index 0b1343c9..6c149a94 100644
--- a/codon/parser/visitors/simplify/simplify.cpp
+++ b/codon/parser/visitors/simplify/simplify.cpp
@@ -88,9 +88,10 @@ SimplifyVisitor::apply(Cache *cache, const StmtPtr &node, const std::string &fil
     }
     // Reserve the following static identifiers.
     for (auto name : {"staticlen", "compile_error", "isinstance", "hasattr", "type",
-                      "TypeVar", "Callable", "argv", "super"})
+                      "TypeVar", "Callable", "argv", "super", "superf"})
       stdlib->generateCanonicalName(name);
     stdlib->add(SimplifyItem::Var, "super", "super", true);
+    stdlib->add(SimplifyItem::Var, "superf", "superf", true);
 
     // This code must be placed in a preamble (these are not POD types but are
     // referenced by the various preamble Function.N and Tuple.N stubs)
diff --git a/codon/parser/visitors/simplify/simplify_stmt.cpp b/codon/parser/visitors/simplify/simplify_stmt.cpp
index 1d0a8823..823301e8 100644
--- a/codon/parser/visitors/simplify/simplify_stmt.cpp
+++ b/codon/parser/visitors/simplify/simplify_stmt.cpp
@@ -550,6 +550,7 @@ void SimplifyVisitor::visit(FunctionStmt *stmt) {
       typeAst = ctx->bases[ctx->bases.size() - 2].ast;
       ctx->bases.back().selfName = name;
       attr.set(".changedSelf");
+      attr.set(Attr::Method);
     }
 
     if (attr.has(Attr::C)) {
@@ -796,6 +797,7 @@ void SimplifyVisitor::visit(ClassStmt *stmt) {
   std::vector<std::unordered_map<std::string, ExprPtr>> substitutions;
   std::vector<int> argSubstitutions;
   std::unordered_set<std::string> seenMembers;
+  std::vector<int> baseASTsFields;
   for (auto &baseClass : stmt->baseClasses) {
     std::string bcName;
     std::vector<ExprPtr> subs;
@@ -836,6 +838,7 @@ void SimplifyVisitor::visit(ClassStmt *stmt) {
         if (!extension)
           ctx->cache->classes[canonicalName].fields.push_back({a.name, nullptr});
       }
+    baseASTsFields.push_back(args.size());
   }
 
   // Add generics, if any, to the context.
@@ -956,6 +959,9 @@ void SimplifyVisitor::visit(ClassStmt *stmt) {
                ctx->moduleName.module);
     ctx->cache->classes[canonicalName].ast =
         N<ClassStmt>(canonicalName, args, N<SuiteStmt>(), attr);
+    for (int i = 0; i < baseASTs.size(); i++)
+      ctx->cache->classes[canonicalName].parentClasses.push_back(
+          {baseASTs[i]->name, baseASTsFields[i]});
     std::vector<StmtPtr> fns;
     ExprPtr codeType = ctx->bases.back().ast->clone();
     std::vector<std::string> magics{};
diff --git a/codon/parser/visitors/typecheck/typecheck.h b/codon/parser/visitors/typecheck/typecheck.h
index 92777c51..91e0aa74 100644
--- a/codon/parser/visitors/typecheck/typecheck.h
+++ b/codon/parser/visitors/typecheck/typecheck.h
@@ -301,6 +301,10 @@ private:
                       const std::vector<types::FuncTypePtr> &methods,
                       const std::vector<CallExpr::Arg> &args);
 
+  ExprPtr transformSuper(const CallExpr *expr);
+  std::vector<types::ClassTypePtr> getSuperTypes(const types::ClassTypePtr &cls);
+
+
 private:
   types::TypePtr unify(types::TypePtr &a, const types::TypePtr &b,
                        bool undoOnSuccess = false);
diff --git a/codon/parser/visitors/typecheck/typecheck_expr.cpp b/codon/parser/visitors/typecheck/typecheck_expr.cpp
index 3007302c..811f28a6 100644
--- a/codon/parser/visitors/typecheck/typecheck_expr.cpp
+++ b/codon/parser/visitors/typecheck/typecheck_expr.cpp
@@ -1038,20 +1038,22 @@ ExprPtr TypecheckVisitor::transformCall(CallExpr *expr, const types::TypePtr &in
       seenNames.insert(i.name);
     }
 
-  if (expr->expr->isId("super")) {
+  if (expr->expr->isId("superf")) {
     if (ctx->bases.back().supers.empty())
-      error("no matching super methods are available");
+      error("no matching superf methods are available");
     auto parentCls = ctx->bases.back().type->getFunc()->funcParent;
     auto m =
         findMatchingMethods(parentCls ? CAST(parentCls, types::ClassType) : nullptr,
                             ctx->bases.back().supers, expr->args);
     if (m.empty())
-      error("no matching super methods are available");
+      error("no matching superf methods are available");
     // LOG("found {} <- {}", ctx->bases.back().type->getFunc()->toString(),
     // m[0]->toString());
     ExprPtr e = N<CallExpr>(N<IdExpr>(m[0]->ast->name), expr->args);
     return transform(e, false, true);
   }
+  if (expr->expr->isId("super"))
+    return transformSuper(expr);
 
   bool isPartial = !expr->args.empty() && expr->args.back().value->getEllipsis() &&
                    !expr->args.back().value->getEllipsis()->isPipeArg &&
@@ -1421,8 +1423,15 @@ std::pair<bool, ExprPtr> TypecheckVisitor::transformSpecialCall(CallExpr *expr)
         expr->args[1].value =
             transformType(expr->args[1].value, /*disableActivation*/ true);
         auto t = expr->args[1].value->type;
-        auto unifyOK = typ->unify(t.get(), nullptr) >= 0;
-        return {true, transform(N<BoolExpr>(unifyOK))};
+        auto hierarchy = getSuperTypes(typ->getClass());
+
+        for (auto &tx: hierarchy) {
+          auto unifyOK = tx->unify(t.get(), nullptr) >= 0;
+          if (unifyOK) {
+            return {true, transform(N<BoolExpr>(true))};
+          }
+        }
+        return {true, transform(N<BoolExpr>(false))};
       }
     }
   } else if (val == "staticlen") {
@@ -1946,5 +1955,91 @@ types::FuncTypePtr TypecheckVisitor::findDispatch(const std::string &fn) {
   return typ;
 }
 
+ExprPtr TypecheckVisitor::transformSuper(const CallExpr *expr) {
+  // For now, we just support casting to the _FIRST_ overload (i.e. empty super())
+  if (!expr->args.empty())
+    error("super does not take arguments");
+
+  if (ctx->bases.empty() || !ctx->bases.back().type)
+    error("no parent classes available");
+  auto fptyp = ctx->bases.back().type->getFunc();
+  if (!fptyp || !fptyp->ast->hasAttr(Attr::Method))
+    error("no parent classes available");
+  if (fptyp->args.size() < 2)
+    error("no parent classes available");
+  ClassTypePtr typ = fptyp->args[1]->getClass();
+  auto &cands = ctx->cache->classes[typ->name].parentClasses;
+  if (cands.empty())
+    error("no parent classes available");
+  //  if (typ->getRecord())
+  //    error("cannot use super on tuple types");
+
+  // find parent typ
+  // unify top N args with parent typ args
+  // realize & do bitcast
+  // call bitcast() . method
+
+  auto name = cands[0].first;
+  int fields = cands[0].second;
+  auto val = ctx->find(name);
+  seqassert(val, "cannot find '{}'", name);
+  auto ftyp = ctx->instantiate(expr, val->type)->getClass();
+
+  if (typ->getRecord()) {
+    std::vector<ExprPtr> members;
+    for (int i = 0; i < fields; i++)
+      members.push_back(N<DotExpr>(N<IdExpr>(fptyp->ast->args[0].name),
+                                   ctx->cache->classes[typ->name].fields[i].name));
+    ExprPtr e = transform(
+        N<CallExpr>(N<IdExpr>(format(TYPE_TUPLE "{}", members.size())), members));
+    unify(e->type, ftyp);
+    e->type = ftyp;
+    return e;
+  } else {
+    for (int i = 0; i < fields; i++) {
+      auto t = ctx->cache->classes[typ->name].fields[i].type;
+      t = ctx->instantiate(expr, t, typ.get());
+
+      auto ft = ctx->cache->classes[name].fields[i].type;
+      ft = ctx->instantiate(expr, ft, ftyp.get());
+      unify(t, ft);
+    }
+
+    ExprPtr typExpr = N<IdExpr>(name);
+    typExpr->setType(ftyp);
+    auto self = fptyp->ast->args[0].name;
+    ExprPtr e = transform(
+        N<CallExpr>(N<DotExpr>(N<IdExpr>("__internal__"), "to_class_ptr"),
+                    N<CallExpr>(N<DotExpr>(N<IdExpr>(self), "__raw__")), typExpr));
+    return e;
+  }
+}
+
+std::vector<ClassTypePtr> TypecheckVisitor::getSuperTypes(const ClassTypePtr &cls) {
+  std::vector<ClassTypePtr> result;
+  if (!cls)
+    return result;
+  result.push_back(cls);
+  int start = 0;
+  for (auto &cand: ctx->cache->classes[cls->name].parentClasses) {
+    auto name = cand.first;
+    int fields = cand.second;
+    auto val = ctx->find(name);
+    seqassert(val, "cannot find '{}'", name);
+    auto ftyp = ctx->instantiate(nullptr, val->type)->getClass();
+    for (int i = start; i < fields; i++) {
+      auto t = ctx->cache->classes[cls->name].fields[i].type;
+      t = ctx->instantiate(nullptr, t, cls.get());
+      auto ft = ctx->cache->classes[name].fields[i].type;
+      ft = ctx->instantiate(nullptr, ft, ftyp.get());
+      unify(t, ft);
+    }
+    start += fields;
+    for (auto &t: getSuperTypes(ftyp))
+      result.push_back(t);
+  }
+  return result;
+}
+
 } // namespace ast
 } // namespace codon
diff --git a/stdlib/internal/internal.codon b/stdlib/internal/internal.codon
index f07c7e50..cfe19211 100644
--- a/stdlib/internal/internal.codon
+++ b/stdlib/internal/internal.codon
@@ -125,6 +125,24 @@ class __internal__:
     def opt_ref_invert[T](what: Optional[T]) -> T:
         ret i8* %what
 
+    @pure
+    @llvm
+    def to_class_ptr[T](ptr: Ptr[byte]) -> T:
+        %0 = bitcast i8* %ptr to {=T}
+        ret {=T} %0
+
+    @pure
+    def _tuple_offsetof(x, field: Static[int]):
+        @llvm
+        def _llvm_offsetof(T: type, idx: Static[int], TE: type) -> int:
+            %a = alloca {=T}
+            %b = getelementptr inbounds {=T}, {=T}* %a, i64 0, i32 {=idx}
+            %base = ptrtoint {=T}* %a to i64
+            %elem = ptrtoint {=TE}* %b to i64
+            %offset = sub i64 %elem, %base
+            ret i64 %offset
+        return _llvm_offsetof(type(x), field, type(x[field]))
+
     def raw_type_str(p: Ptr[byte], name: str) -> str:
         pstr = p.__repr__()
         # '<[name] at [pstr]>'
diff --git a/test/parser/typecheck_expr.codon b/test/parser/typecheck_expr.codon
index ce02e25b..f28f1b87 100644
--- a/test/parser/typecheck_expr.codon
+++ b/test/parser/typecheck_expr.codon
@@ -600,6 +600,30 @@ print hasattr(int, "__getitem__")
 print hasattr([1, 2], "__getitem__", str)
 #: False
 
+#%% isinstance_inheritance,barebones
+class AX[T]:
+    a: T
+    def __init__(self, a: T):
+        self.a = a
+class Side:
+    def __init__(self):
+        pass
+class BX[T,U](AX[T], Side):
+    b: U
+    def __init__(self, a: T, b: U):
+        super().__init__(a)
+        self.b = b
+class CX[T,U](BX[T,U]):
+    c: int
+    def __init__(self, a: T, b: U):
+        super().__init__(a, b)
+        self.c = 1
+c = CX('a', False)
+print isinstance(c, CX), isinstance(c, BX), isinstance(c, AX), isinstance(c, Side)
+#: True True True True
+print isinstance(c, BX[str, bool]), isinstance(c, BX[str, str]), isinstance(c, AX[int])
+#: True False False
+
 #%% staticlen_err,barebones
 print staticlen([1, 2]) #! List[int] is not a tuple type
 
@@ -679,3 +703,83 @@ def foo(x: Callable[[1,2], 3]): pass  #! unexpected static type
 
 #%% static_unify_2,barebones
 def foo(x: List[1]): pass  #! cannot unify T and 1
+
+#%% super,barebones
+class A[T]:
+    a: T
+    def __init__(self, t: T):
+        self.a = t
+    def foo(self):
+        return f'A:{self.a}'
+class B(A[str]):
+    b: int
+    def __init__(self):
+        super().__init__('s')
+        self.b = 6
+    def baz(self):
+        return f'{super().foo()}::{self.b}'
+b = B()
+print b.foo() #: A:s
+print b.baz() #: A:s::6
+
+class AX[T]:
+    a: T
+    def __init__(self, a: T):
+        self.a = a
+    def foo(self):
+        return f'[AX:{self.a}]'
+class BX[T,U](AX[T]):
+    b: U
+    def __init__(self, a: T, b: U):
+        print super().__class__
+        super().__init__(a)
+        self.b = b
+    def foo(self):
+        return f'[BX:{super().foo()}:{self.b}]'
+class CX[T,U](BX[T,U]):
+    c: int
+    def __init__(self, a: T, b: U):
+        print super().__class__
+        super().__init__(a, b)
+        self.c = 1
+    def foo(self):
+        return f'CX:{super().foo()}:{self.c}'
+c = CX('a', False)
+print c.__class__, c.foo()
+#: BX[str,bool]
+#: AX[str]
+#: CX[str,bool] CX:[BX:[AX:a]:False]:1
+
+
+#%% super_tuple,barebones
+@tuple
+class A[T]:
+    a: T
+    x: int
+    def __new__(a: T) -> A[T]:
+        return (a, 1)
+    def foo(self):
+        return f'A:{self.a}'
+@tuple
+class B(A[str]):
+    b: int
+    def __new__() -> B:
+        return (*(A('s')), 6)
+    def baz(self):
+        return f'{super().foo()}::{self.b}'
+
+b = B()
+print b.foo() #: A:s
+print b.baz() #: A:s::6
+
+
+#%% super_error,barebones
+class A:
+    def __init__(self):
+        super().__init__()
+a = A()
+#! no parent classes available
+#! while realizing A.__init__:1 (arguments A.__init__:1[A])
+
+#%% super_error_2,barebones
+super().foo(1) #! no parent classes available
diff --git a/test/parser/typecheck_stmt.codon b/test/parser/typecheck_stmt.codon
index a3099c5c..1baa0fcd 100644
--- a/test/parser/typecheck_stmt.codon
+++ b/test/parser/typecheck_stmt.codon
@@ -299,19 +299,19 @@ def foo2(x):
 foo2(1) #: 2
 foo2('s') #: 1
 
-#%% super,barebones
+#%% superf,barebones
 class Foo:
     def foo(a):
-        # super(a)
+        # superf(a)
         print 'foo-1', a
     def foo(a: int):
-        super(a)
+        superf(a)
         print 'foo-2', a
     def foo(a: str):
-        super(a)
+        superf(a)
         print 'foo-3', a
     def foo(a):
-        super(a)
+        superf(a)
         print 'foo-4', a
 Foo.foo(1)
 #: foo-1 1
@@ -324,21 +324,21 @@ class Bear:
 @extend
 class Bear:
     def woof(x):
-        return super(x) + f' bear w--f {x}'
+        return superf(x) + f' bear w--f {x}'
 print Bear.woof('!')
 #: bear woof ! bear w--f !
 
 class PolarBear(Bear):
     def woof():
-        return 'polar ' + super('@')
+        return 'polar ' + superf('@')
 print PolarBear.woof()
 #: polar bear woof @ bear w--f @
 
-#%% super_error,barebones
+#%% superf_error,barebones
 class Foo:
     def foo(a):
-        super(a)
+        superf(a)
         print 'foo-1', a
 Foo.foo(1)
-#! no matching super methods are available
+#! no matching superf methods are available
 #! while realizing Foo.foo:0