diff --git a/include/llmr/map/filter_expression.hpp b/include/llmr/map/filter_expression.hpp
new file mode 100644
index 000000000..d536a5a34
--- /dev/null
+++ b/include/llmr/map/filter_expression.hpp
@@ -0,0 +1,102 @@
+#ifndef LLMR_MAP_FILTER_EXPRESSION
+#define LLMR_MAP_FILTER_EXPRESSION
+
+#include <llmr/style/value.hpp>
+#include <llmr/util/recursive_wrapper.hpp>
+
+#include <vector>
+#include <string>
+
+namespace llmr {
+
+enum class FilterOperator {
+    Equal,
+    NotEqual
+};
+
+enum class ExpressionOperator {
+    Or,
+    And
+};
+
+
+inline FilterOperator filterOperatorType(const std::string &op) {
+    if (op == "!=" || op == "not") {
+        return FilterOperator::NotEqual;
+    } else if (op == "==" || op == "eq") {
+        return FilterOperator::Equal;
+    } else {
+        fprintf(stderr, "[WARNING] filter operator '%s' unrecognized\n", op.c_str());
+        return FilterOperator::Equal;
+    }
+}
+
+inline ExpressionOperator expressionOperatorType(const std::string &op) {
+    if (op == "&&" || op == "and") {
+        return ExpressionOperator::And;
+    } else if (op == "||" || op == "or") {
+        return ExpressionOperator::Or;
+    } else {
+        fprintf(stderr, "[WARNING] expression operator '%s' unrecognized\n", op.c_str());
+        return ExpressionOperator::Or;
+    }
+}
+
+
+
+class PropertyExpression;
+
+class PropertyFilter {
+public:
+    inline PropertyFilter(const std::string &field, FilterOperator op, const Value &value) : field(field), op(op), value(value) {};
+    inline PropertyFilter(PropertyFilter &&filter)
+        : field(std::move(filter.field)),
+          op(filter.op),
+          value(std::move(filter.value)) {
+    }
+
+    // Returns true if the filter passes, even if the key is missing.
+    inline bool isMissingFieldOkay() const {
+        switch (op) {
+        case FilterOperator::NotEqual:
+            return true;
+        default:
+            return false;
+        }
+    }
+
+    inline bool compare(const Value &other) const {
+        switch (op) {
+        case FilterOperator::NotEqual:
+            return !util::relaxed_equal(value)(other);
+        default:
+            return util::relaxed_equal(value)(other);
+        }
+    }
+
+public:
+    std::string field;
+    FilterOperator op = FilterOperator::Equal;
+    Value value;
+};
+
+typedef util::variant<PropertyFilter, util::recursive_wrapper<PropertyExpression>> PropertyFilterExpression;
+
+
+class PropertyExpression {
+public:
+    inline PropertyExpression() {}
+    inline PropertyExpression(PropertyExpression &&expression)
+        : op(expression.op),
+          operands(std::move(expression.operands)) {
+    }
+
+public:
+    ExpressionOperator op = ExpressionOperator::Or;
+    std::vector<PropertyFilterExpression> operands;
+};
+
+
+}
+
+#endif
diff --git a/include/llmr/util/recursive_wrapper.hpp b/include/llmr/util/recursive_wrapper.hpp
new file mode 100644
index 000000000..557b576c0
--- /dev/null
+++ b/include/llmr/util/recursive_wrapper.hpp
@@ -0,0 +1,132 @@
+#ifndef LLMR_UTIL_VARIANT_RECURSIVE_WRAPPER_HPP
+#define LLMR_UTIL_VARIANT_RECURSIVE_WRAPPER_HPP
+
+#include <utility>
+
+namespace llmr {
+
+namespace util {
+
+template <typename T>
+class recursive_wrapper
+{
+public:
+
+    typedef T type;
+
+private:
+
+    T* p_;
+
+public:
+
+    ~recursive_wrapper();
+    recursive_wrapper();
+
+    recursive_wrapper(recursive_wrapper const& operand);
+    recursive_wrapper(T const& operand);
+    recursive_wrapper(recursive_wrapper&& operand);
+    recursive_wrapper(T&& operand);
+
+private:
+
+    void assign(const T& rhs);
+
+public:
+
+    recursive_wrapper& operator=(const recursive_wrapper& rhs)
+    {
+        assign( rhs.get() );
+        return *this;
+    }
+
+    recursive_wrapper& operator=(const T& rhs)
+    {
+        assign( rhs );
+        return *this;
+    }
+
+    void swap(recursive_wrapper& operand) noexcept
+    {
+        T* temp = operand.p_;
+        operand.p_ = p_;
+        p_ = temp;
+    }
+
+
+    recursive_wrapper& operator=(recursive_wrapper&& rhs) noexcept
+    {
+        swap(rhs);
+        return *this;
+    }
+
+    recursive_wrapper& operator=(T&& rhs)
+    {
+        get() = std::move(rhs);
+        return *this;
+    }
+
+
+public:
+
+    T& get() { return *get_pointer(); }
+    const T& get() const { return *get_pointer(); }
+
+    T* get_pointer() { return p_; }
+    const T* get_pointer() const { return p_; }
+
+};
+
+template <typename T>
+recursive_wrapper<T>::~recursive_wrapper()
+{
+    delete p_;
+}
+
+template <typename T>
+recursive_wrapper<T>::recursive_wrapper()
+    : p_(new T)
+{
+}
+
+template <typename T>
+recursive_wrapper<T>::recursive_wrapper(recursive_wrapper const& operand)
+    : p_(new T( operand.get() ))
+{
+}
+
+template <typename T>
+recursive_wrapper<T>::recursive_wrapper(T const& operand)
+    : p_(new T(operand))
+{
+}
+
+template <typename T>
+recursive_wrapper<T>::recursive_wrapper(recursive_wrapper&& operand)
+    : p_(new T( std::move(operand.get()) ))
+{
+}
+
+template <typename T>
+recursive_wrapper<T>::recursive_wrapper(T&& operand)
+    : p_(new T( std::move(operand) ))
+{
+}
+
+template <typename T>
+void recursive_wrapper<T>::assign(const T& rhs)
+{
+    this->get() = rhs;
+}
+
+template <typename T>
+inline void swap(recursive_wrapper<T>& lhs, recursive_wrapper<T>& rhs) noexcept
+{
+    lhs.swap(rhs);
+}
+
+}
+
+}
+
+#endif // LLMR_UTIL_VARIANT_RECURSIVE_WRAPPER_HPP