diff --git a/src/sled/futures/future.h b/src/sled/futures/future.h
index b70fc71..4ca0f2e 100644
--- a/src/sled/futures/future.h
+++ b/src/sled/futures/future.h
@@ -10,8 +10,9 @@
 #include "sled/synchronization/event.h"
 #include "sled/synchronization/mutex.h"
 #include "sled/task_queue/task_queue_base.h"
-#include "sled/variant.h"
+#include "sled/utility/forward_on_copy.h"
 #include <atomic>
+#include <future>
 #include <list>
 
 namespace sled {
@@ -48,7 +49,8 @@ struct FutureData {
     ~FutureData() { DecrementFuturesUsage(); }
 
     std::atomic_int state{kNotCompletedFuture};
-    sled::variant<sled::monostate, T, FailureT> value;
+    // sled::variant<sled::monostate, T, FailureT> value;
+    sled::any value;
     std::list<std::function<void(const T &)>> success_callbacks;
     std::list<std::function<void(const FailureT &)>> failure_callbacks;
     sled::Mutex mutex_;
@@ -130,7 +132,8 @@ public:
         if (!IsCompleted()) Wait();
         if (IsSucceeded()) {
             try {
-                return sled::get<T>(data_->value);
+                // return sled::get<T>(data_->value);
+                return sled::any_cast<T>(data_->value);
             } catch (...) {}
         }
         return T();
@@ -140,7 +143,8 @@ public:
     {
         SLED_ASSERT(data_ != nullptr, "Future is not valid");
         if (!IsCompleted()) { Wait(); }
-        return sled::get<T>(data_->value);
+        // return sled::get<T>(data_->value);
+        return sled::any_cast<T>(data_->value);
     }
 
     FailureT FailureReason() const
@@ -149,7 +153,8 @@ public:
         if (!IsCompleted()) { Wait(); }
         if (IsFailed()) {
             try {
-                return sled::get<FailureT>(data_->value);
+                // return sled::get<FailureT>(data_->value);
+                return sled::any_cast<FailureT>(data_->value);
             } catch (...) {}
         }
         return FailureT();
@@ -176,7 +181,8 @@ public:
         }
         if (call_it) {
             try {
-                f(sled::get<T>(data_->value));
+                // f(sled::get<T>(data_->value));
+                f(sled::any_cast<T>(data_->value));
             } catch (...) {}
         }
         return Future<T, FailureT>(data_);
@@ -203,7 +209,8 @@ public:
         }
         if (call_it) {
             try {
-                f(sled::get<FailureT>(data_->value));
+                // f(sled::get<FailureT>(data_->value));
+                f(sled::any_cast<FailureT>(data_->value));
             } catch (...) {}
         }
         return Future<T, FailureT>(data_);
@@ -294,6 +301,20 @@ public:
         return result;
     }
 
+    template<typename Func, typename U = decltype(std::declval<eggs::invoke_result_t<Func, T>().Result()>)>
+    Future<U, FailureT> AndThen(Func &&f) const noexcept
+    {
+        return FlatMap([f](const T &) { return f(); });
+    }
+
+    template<typename T2, typename U = typename std::decay<T2>::type>
+    Future<U, FailureT> AndThenValue(T2 &&value) const noexcept
+    {
+        Future<U, FailureT> result = Future<U, FailureT>::Create();
+        auto forward_on_copy       = sled::MakeForwardOnCopy(std::forward<T2>(value));
+        return Map([forward_on_copy](const T &) noexcept { return forward_on_copy.value(); });
+    }
+
     Future<T, FailureT> Via(TaskQueueBase *task_queue) const noexcept
     {
         SLED_ASSERT(task_queue != nullptr, "TaskQueue is not valid");
@@ -365,6 +386,7 @@ private:
             if (IsCompleted()) { return; }
 
             try {
+                // data_->value.template emplace<T>(std::move(value));
                 // data_->value.template emplace<T>(std::move(value));
                 data_->value = std::move(value);
             } catch (...) {}
@@ -376,7 +398,8 @@ private:
 
         for (const auto &f : callbacks) {
             try {
-                f(sled::get<T>(data_->value));
+                // f(sled::get<T>(data_->value));
+                f(sled::any_cast<T>(data_->value));
             } catch (...) {}
         }
     }
@@ -396,6 +419,7 @@ private:
             if (IsCompleted()) { return; }
             try {
                 // data_->value.template emplace<FailureT>(std::move(reason));
+                // data_->value = std::move(reason);
                 data_->value = std::move(reason);
             } catch (...) {}
             data_->state.store(detail::kFailedFuture, std::memory_order_release);
@@ -406,7 +430,8 @@ private:
 
         for (const auto &f : callbacks) {
             try {
-                f(sled::get<FailureT>(data_->value));
+                // f(sled::get<FailureT>(data_->value));
+                f(sled::any_cast<FailureT>(data_->value));
             } catch (...) {}
         }
     }
diff --git a/src/sled/futures/future_test.cc b/src/sled/futures/future_test.cc
index fb9c47a..82b1290 100644
--- a/src/sled/futures/future_test.cc
+++ b/src/sled/futures/future_test.cc
@@ -1,9 +1,11 @@
 #include <sled/futures/future.h>
 #include <sled/system/thread.h>
+#include <type_traits>
 
 TEST_SUITE("future")
 {
     TEST_CASE("base success")
+
     {
         sled::Promise<int, std::string> p;
         auto f = p.GetFuture();
@@ -12,6 +14,7 @@ TEST_SUITE("future")
         CHECK(f.IsValid());
         CHECK_EQ(f.Result(), 42);
     }
+
     TEST_CASE("base failed")
     {
         sled::Promise<int, std::string> p;
@@ -23,31 +26,65 @@ TEST_SUITE("future")
         CHECK(f.IsValid());
         CHECK_EQ(f.FailureReason(), "error");
     }
+
+    TEST_CASE("throw")
+    {
+        sled::Promise<int, std::string> p;
+        auto f = p.GetFuture().Map([](int x) {
+            throw std::runtime_error("test");
+            return x;
+        });
+
+        p.Success(42);
+        REQUIRE(f.IsCompleted());
+        REQUIRE(f.IsFailed());
+        CHECK_EQ(f.FailureReason(), "test");
+    }
+
+    TEST_CASE("base failed")
+    {
+        sled::Promise<int, std::string> p;
+        auto f = p.GetFuture();
+        p.Failure("error");
+        REQUIRE(p.IsFilled());
+        REQUIRE(f.IsCompleted());
+        CHECK(f.Wait(-1));
+        CHECK(f.IsValid());
+        CHECK_EQ(f.FailureReason(), "error");
+    }
+
     TEST_CASE("thread success") {}
 
-    TEST_CASE("map")
+    TEST_CASE("Map")
     {
         sled::Promise<int, std::string> p;
         auto f  = p.GetFuture();
-        auto f2 = f.Map([](int i) { return i + 1; });
+        auto f2 = f.Map([](int i) { return i + 1; })
+                      .Map([](int i) { return std::to_string(i) + "00"; })
+                      .Map([](const std::string &str) {
+                          std::stringstream ss(str);
+                          int x;
+                          ss >> x;
+                          return x;
+                      });
         p.Success(42);
         CHECK(f2.Wait(-1));
-        CHECK_EQ(f2.Result(), 43);
+        CHECK_EQ(f2.Result(), 4300);
     }
 
     TEST_CASE("FlatMap")
     {
-        // sled::Promise<int, std::string> p;
-        // auto f = p.GetFuture().FlatMap([](int i) {
-        //     auto str = std::to_string(i);
-        //     sled::Promise<std::string, std::string> p;
-        //     p.Success(str);
-        //
-        //     return p.GetFuture();
-        // });
-        // p.Success(42);
-        // CHECK(f.Wait(-1));
-        // CHECK_EQ(f.Result(), "42");
+        sled::Promise<int, std::string> p;
+        auto f = p.GetFuture().FlatMap([](int i) {
+            auto str = std::to_string(i);
+            sled::Promise<std::string, std::string> p;
+            p.Success(str);
+
+            return p.GetFuture();
+        });
+        p.Success(42);
+        CHECK(f.IsCompleted());
+        CHECK_EQ(f.Result(), "42");
     }
 
     TEST_CASE("Via")
diff --git a/src/sled/utility/forward_on_copy.h b/src/sled/utility/forward_on_copy.h
new file mode 100644
index 0000000..53bff08
--- /dev/null
+++ b/src/sled/utility/forward_on_copy.h
@@ -0,0 +1,76 @@
+#ifndef SLED_UTILITY_FORWARD_ON_COPY_H
+#define SLED_UTILITY_FORWARD_ON_COPY_H
+
+#pragma once
+#include "sled/any.h"
+
+namespace sled {
+namespace detail {
+
+struct ForwardOnCopyTag {};
+
+};// namespace detail
+
+template<typename T>
+struct ForwardOnCopy {
+    ForwardOnCopy(ForwardOnCopy &other)
+        : is_moved_(other.is_moved_),
+          value_(is_moved_ ? other.value_ : std::move(other.value_))
+    {}
+
+    // ForwardOnCopy(ForwardOnCopy &&other) noexcept;
+    ForwardOnCopy &operator=(ForwardOnCopy &other)
+    {
+        is_moved_ = other.is_moved_;
+        value_    = is_moved_ ? other.value_ : std::move(other.value_);
+        return *this;
+    }
+
+    // ForwardOnCopy &operator=(ForwardOnCopy &&other) noexcept;
+    T value() const
+    {
+        if (is_moved_) {
+            return std::move(sled::any_cast<T>(value_));
+        } else {
+            return sled::any_cast<T>(value_);
+        }
+    }
+
+private:
+    bool is_moved_;
+    sled::any value_;
+};
+
+template<typename T>
+ForwardOnCopy<T>
+MakeForwardOnCopy(T value)
+{
+    ForwardOnCopy<T> result;
+    result.is_moved_ = false;
+    result.value_    = value;
+    return result;
+}
+
+template<typename T>
+ForwardOnCopy<T>
+MakeForwardOnCopy(T &value)
+{
+    ForwardOnCopy<T> result;
+    result.is_moved_ = false;
+    result.value_    = value;
+    return result;
+}
+
+template<typename T>
+ForwardOnCopy<T>
+MakeForwardOnCopy(T &&value)
+{
+    ForwardOnCopy<T> result;
+    result.is_moved_ = true;
+    result.value_    = std::move(value);
+    return result;
+}
+
+}// namespace sled
+
+#endif// SLED_UTILITY_FORWARD_ON_COPY_H