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diff --git a/src/scheduler.h b/src/scheduler.h
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+// Copyright (c) 2015-2017 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_SCHEDULER_H
+#define BITCOIN_SCHEDULER_H
+
+//
+// NOTE:
+// boost::thread / boost::chrono should be ported to std::thread / std::chrono
+// when we support C++11.
+//
+#include <boost/chrono/chrono.hpp>
+#include <boost/thread.hpp>
+#include <map>
+
+#include <sync.h>
+
+//
+// Simple class for background tasks that should be run
+// periodically or once "after a while"
+//
+// Usage:
+//
+// CScheduler* s = new CScheduler();
+// s->scheduleFromNow(doSomething, 11); // Assuming a: void doSomething() { }
+// s->scheduleFromNow(std::bind(Class::func, this, argument), 3);
+// boost::thread* t = new boost::thread(boost::bind(CScheduler::serviceQueue, s));
+//
+// ... then at program shutdown, clean up the thread running serviceQueue:
+// t->interrupt();
+// t->join();
+// delete t;
+// delete s; // Must be done after thread is interrupted/joined.
+//
+
+class CScheduler
+{
+public:
+    CScheduler();
+    ~CScheduler();
+
+    typedef std::function<void(void)> Function;
+
+    // Call func at/after time t
+    void schedule(Function f, boost::chrono::system_clock::time_point t=boost::chrono::system_clock::now());
+
+    // Convenience method: call f once deltaSeconds from now
+    void scheduleFromNow(Function f, int64_t deltaMilliSeconds);
+
+    // Another convenience method: call f approximately
+    // every deltaSeconds forever, starting deltaSeconds from now.
+    // To be more precise: every time f is finished, it
+    // is rescheduled to run deltaSeconds later. If you
+    // need more accurate scheduling, don't use this method.
+    void scheduleEvery(Function f, int64_t deltaMilliSeconds);
+
+    // To keep things as simple as possible, there is no unschedule.
+
+    // Services the queue 'forever'. Should be run in a thread,
+    // and interrupted using boost::interrupt_thread
+    void serviceQueue();
+
+    // Tell any threads running serviceQueue to stop as soon as they're
+    // done servicing whatever task they're currently servicing (drain=false)
+    // or when there is no work left to be done (drain=true)
+    void stop(bool drain=false);
+
+    // Returns number of tasks waiting to be serviced,
+    // and first and last task times
+    size_t getQueueInfo(boost::chrono::system_clock::time_point &first,
+                        boost::chrono::system_clock::time_point &last) const;
+
+    // Returns true if there are threads actively running in serviceQueue()
+    bool AreThreadsServicingQueue() const;
+
+private:
+    std::multimap<boost::chrono::system_clock::time_point, Function> taskQueue;
+    boost::condition_variable newTaskScheduled;
+    mutable boost::mutex newTaskMutex;
+    int nThreadsServicingQueue;
+    bool stopRequested;
+    bool stopWhenEmpty;
+    bool shouldStop() const { return stopRequested || (stopWhenEmpty && taskQueue.empty()); }
+};
+
+/**
+ * Class used by CScheduler clients which may schedule multiple jobs
+ * which are required to be run serially. Does not require such jobs
+ * to be executed on the same thread, but no two jobs will be executed
+ * at the same time.
+ */
+class SingleThreadedSchedulerClient {
+private:
+    CScheduler *m_pscheduler;
+
+    CCriticalSection m_cs_callbacks_pending;
+    std::list<std::function<void (void)>> m_callbacks_pending;
+    bool m_are_callbacks_running = false;
+
+    void MaybeScheduleProcessQueue();
+    void ProcessQueue();
+
+public:
+    explicit SingleThreadedSchedulerClient(CScheduler *pschedulerIn) : m_pscheduler(pschedulerIn) {}
+    void AddToProcessQueue(std::function<void (void)> func);
+
+    // Processes all remaining queue members on the calling thread, blocking until queue is empty
+    // Must be called after the CScheduler has no remaining processing threads!
+    void EmptyQueue();
+
+    size_t CallbacksPending();
+};
+
+#endif