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diff --git a/Swiften/Base/LRUCache.h b/Swiften/Base/LRUCache.h
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+/*
+ * Copyright (c) 2017 Isode Limited.
+ * All rights reserved.
+ * See the COPYING file for more information.
+ */
+
+#pragma once
+
+#include <functional>
+#include <utility>
+
+#include <boost/multi_index_container.hpp>
+#include <boost/multi_index/member.hpp>
+#include <boost/multi_index/hashed_index.hpp>
+#include <boost/multi_index/sequenced_index.hpp>
+#include <boost/optional.hpp>
+
+namespace Swift {
+
+
+/**
+ * The \ref LRUCache template class implements a lookup cache which removes
+ * the least recently used cached item from the cache, if the cache size hits
+ * the \p MAX_SIZE limit.
+ *
+ * An example use is a cache for entity capabilities hash to DiscoInfo.
+ */
+template <typename KEY_TYPE, typename VALUE_TYPE, size_t MAX_SIZE>
+class LRUCache {
+public:
+    using cacheMissFunction = std::function<boost::optional<VALUE_TYPE>(const KEY_TYPE& )>;
+
+public:
+    /**
+     * Inserts the key/value pair in the front of the cache. If the \p key
+     * already exists in the cache, it is moved to the front instead. If
+     * afterwards, the cahe size exceeds the \p MAX_SIZE limit, the least
+     * recently item is removed from the cache.
+     */
+    void insert(const KEY_TYPE& key, VALUE_TYPE value) {
+        auto pushResult = cache.push_front(entry_t(key, value));
+        if (!pushResult.second) {
+            cache.relocate(cache.begin(), pushResult.first);
+        }
+        else if (cache.size() > MAX_SIZE) {
+          cache.pop_back();
+        }
+    }
+
+    /**
+     * Looks up a cache entry based on the provided \p key and moves it back
+     * to the front of the cache. If there is no cache entry for the provided
+     * \p key, an uninitialized \p boost::optional is returned.
+     * If the optional \p missFunction is provided, it is called on a cache miss.
+     * If the \p missFunction returns an initialized \p boost::optional, the
+     * value is inserted in the cache.
+     */
+    boost::optional<VALUE_TYPE> get(const KEY_TYPE& key, cacheMissFunction missFunction = cacheMissFunction()) {
+        boost::optional<VALUE_TYPE> cachedValue;
+        auto cacheItemIterator = boost::multi_index::get<1>(cache).find(key);
+        if (cacheItemIterator != boost::multi_index::get<1>(cache).end()) {
+            cachedValue = cacheItemIterator->second;
+            cache.relocate(cache.begin(), cache.iterator_to(*cacheItemIterator));
+        }
+        else if (missFunction && (cachedValue = missFunction(key))) {
+            insert(key, cachedValue.get());
+        }
+        return cachedValue;
+    }
+
+private:
+    using entry_t =  std::pair<KEY_TYPE, VALUE_TYPE>;
+
+private:
+    boost::multi_index_container< entry_t, boost::multi_index::indexed_by< boost::multi_index::sequenced<>, boost::multi_index::hashed_unique<
+    BOOST_MULTI_INDEX_MEMBER(entry_t, KEY_TYPE, first)> > > cache;
+};
+
+}