diff --git a/src/opt/bcd2.cpp b/src/opt/bcd2.cpp
index 766e0d84a..e69275b27 100644
--- a/src/opt/bcd2.cpp
+++ b/src/opt/bcd2.cpp
@@ -99,7 +99,7 @@ namespace opt {
         }
 
     public:
-        bcd2(context& c,
+        bcd2(maxsat_context& c,
              weights_t& ws, expr_ref_vector const& soft): 
             maxsmt_solver_base(c, ws, soft),
             pb(m),
@@ -399,7 +399,7 @@ namespace opt {
     };
 
     maxsmt_solver_base* mk_bcd2(
-        context& c, weights_t& ws, expr_ref_vector const& soft) {
+        maxsat_context& c, weights_t& ws, expr_ref_vector const& soft) {
         return alloc(bcd2, c, ws, soft);
     }
 
diff --git a/src/opt/bcd2.h b/src/opt/bcd2.h
index 79d528e20..bd9c3d344 100644
--- a/src/opt/bcd2.h
+++ b/src/opt/bcd2.h
@@ -23,6 +23,6 @@ Notes:
 #include "maxsmt.h"
 
 namespace opt {
-    maxsmt_solver_base* mk_bcd2(context& c, weights_t& ws, expr_ref_vector const& soft);
+    maxsmt_solver_base* mk_bcd2(maxsat_context& c, weights_t& ws, expr_ref_vector const& soft);
 }
 #endif
diff --git a/src/opt/fu_malik.cpp b/src/opt/fu_malik.cpp
index 6d2386b96..7a3f685e6 100644
--- a/src/opt/fu_malik.cpp
+++ b/src/opt/fu_malik.cpp
@@ -50,7 +50,7 @@ namespace opt {
         model_ref       m_model;
 
     public:
-        fu_malik(context& c, weights_t& ws, expr_ref_vector const& soft):
+        fu_malik(maxsat_context& c, weights_t& ws, expr_ref_vector const& soft):
             maxsmt_solver_base(c, ws, soft),
             m_fm(c.fm()),
             m_aux_soft(soft),
@@ -229,7 +229,7 @@ namespace opt {
         }
     };
 
-    maxsmt_solver_base* mk_fu_malik(context& c, weights_t & ws, expr_ref_vector const& soft) {
+    maxsmt_solver_base* mk_fu_malik(maxsat_context& c, weights_t & ws, expr_ref_vector const& soft) {
         return alloc(fu_malik, c, ws, soft);
     }
 
diff --git a/src/opt/fu_malik.h b/src/opt/fu_malik.h
index 5eea9fc49..7c6369f6a 100644
--- a/src/opt/fu_malik.h
+++ b/src/opt/fu_malik.h
@@ -29,7 +29,7 @@ Notes:
 
 namespace opt {
 
-    maxsmt_solver_base* mk_fu_malik(context& c, weights_t & ws, expr_ref_vector const& soft);
+    maxsmt_solver_base* mk_fu_malik(maxsat_context& c, weights_t & ws, expr_ref_vector const& soft);
 
     
 };
diff --git a/src/opt/maxhs.cpp b/src/opt/maxhs.cpp
index 6d4a7b8bf..9ce9844b5 100644
--- a/src/opt/maxhs.cpp
+++ b/src/opt/maxhs.cpp
@@ -75,7 +75,7 @@ namespace opt {
 
 
     public:
-        maxhs(context& c, weights_t& ws, expr_ref_vector const& soft):
+        maxhs(maxsat_context& c, weights_t& ws, expr_ref_vector const& soft):
             maxsmt_solver_base(c, ws, soft), 
             m_aux(m), 
             m_at_lower_bound(false) {
@@ -554,7 +554,7 @@ namespace opt {
     };
 
     maxsmt_solver_base* mk_maxhs(
-        context& c, weights_t& ws, expr_ref_vector const& soft) {
+        maxsat_context& c, weights_t& ws, expr_ref_vector const& soft) {
         return alloc(maxhs, c, ws, soft);
     }
 
diff --git a/src/opt/maxhs.h b/src/opt/maxhs.h
index f31cbce9f..ed59bf625 100644
--- a/src/opt/maxhs.h
+++ b/src/opt/maxhs.h
@@ -23,7 +23,7 @@ Notes:
 #include "maxsmt.h"
 
 namespace opt {
-    maxsmt_solver_base* mk_maxhs(context& c,
+    maxsmt_solver_base* mk_maxhs(maxsat_context& c,
                                  weights_t& ws, expr_ref_vector const& soft);
 }
 #endif
diff --git a/src/opt/maxres.cpp b/src/opt/maxres.cpp
index c9b52f370..ddd238156 100644
--- a/src/opt/maxres.cpp
+++ b/src/opt/maxres.cpp
@@ -107,7 +107,7 @@ private:
     typedef ptr_vector<expr> exprs;
 
 public:
-    maxres(context& c,
+    maxres(maxsat_context& c,
            weights_t& ws, expr_ref_vector const& soft, 
            strategy_t st):
         maxsmt_solver_base(c, ws, soft),
@@ -788,12 +788,12 @@ public:
 };
 
 opt::maxsmt_solver_base* opt::mk_maxres(
-    context& c, weights_t& ws, expr_ref_vector const& soft) {
+    maxsat_context& c, weights_t& ws, expr_ref_vector const& soft) {
     return alloc(maxres, c, ws, soft, maxres::s_primal);
 }
 
 opt::maxsmt_solver_base* opt::mk_primal_dual_maxres(
-    context& c, weights_t& ws, expr_ref_vector const& soft) {
+    maxsat_context& c, weights_t& ws, expr_ref_vector const& soft) {
     return alloc(maxres, c, ws, soft, maxres::s_primal_dual);
 }
 
diff --git a/src/opt/maxres.h b/src/opt/maxres.h
index c942b655e..bb280cb29 100644
--- a/src/opt/maxres.h
+++ b/src/opt/maxres.h
@@ -22,9 +22,9 @@ Notes:
 
 namespace opt {
 
-    maxsmt_solver_base* mk_maxres(context& c, weights_t & ws, expr_ref_vector const& soft);
+    maxsmt_solver_base* mk_maxres(maxsat_context& c, weights_t & ws, expr_ref_vector const& soft);
 
-    maxsmt_solver_base* mk_primal_dual_maxres(context& c, weights_t & ws, expr_ref_vector const& soft);
+    maxsmt_solver_base* mk_primal_dual_maxres(maxsat_context& c, weights_t & ws, expr_ref_vector const& soft);
 
 };
 
diff --git a/src/opt/maxsls.cpp b/src/opt/maxsls.cpp
index fc9c71607..d5ddb6623 100644
--- a/src/opt/maxsls.cpp
+++ b/src/opt/maxsls.cpp
@@ -26,7 +26,7 @@ namespace opt {
 
     class sls : public maxsmt_solver_base {
     public:
-        sls(context& c, weights_t& ws, expr_ref_vector const& soft): 
+        sls(maxsat_context& c, weights_t& ws, expr_ref_vector const& soft): 
             maxsmt_solver_base(c, ws, soft) {
         }
         virtual ~sls() {}
@@ -54,7 +54,7 @@ namespace opt {
     };
 
     maxsmt_solver_base* mk_sls(
-        context& c, weights_t& ws, expr_ref_vector const& soft) {
+        maxsat_context& c, weights_t& ws, expr_ref_vector const& soft) {
         return alloc(sls, c, ws, soft);
     }
 
diff --git a/src/opt/maxsls.h b/src/opt/maxsls.h
index c4314171f..f344c1564 100644
--- a/src/opt/maxsls.h
+++ b/src/opt/maxsls.h
@@ -27,7 +27,7 @@ Notes:
 namespace opt {
 
 
-    maxsmt_solver_base* mk_sls(context& c, weights_t& ws, expr_ref_vector const& soft);
+    maxsmt_solver_base* mk_sls(maxsat_context& c, weights_t& ws, expr_ref_vector const& soft);
 
     
 };
diff --git a/src/opt/maxsmt.cpp b/src/opt/maxsmt.cpp
index 710f10d48..92dac9474 100644
--- a/src/opt/maxsmt.cpp
+++ b/src/opt/maxsmt.cpp
@@ -36,7 +36,7 @@ Notes:
 namespace opt {
 
     maxsmt_solver_base::maxsmt_solver_base(
-        context& c, vector<rational> const& ws, expr_ref_vector const& soft):
+        maxsat_context& c, vector<rational> const& ws, expr_ref_vector const& soft):
         m(c.get_manager()), 
         m_c(c),
         m_cancel(false), 
@@ -156,7 +156,7 @@ namespace opt {
 
 
 
-    maxsmt::maxsmt(context& c):
+    maxsmt::maxsmt(maxsat_context& c):
         m(c.get_manager()), m_c(c), m_cancel(false), 
         m_soft_constraints(m), m_answer(m) {}
 
diff --git a/src/opt/maxsmt.h b/src/opt/maxsmt.h
index 356a2d50b..a2881ad21 100644
--- a/src/opt/maxsmt.h
+++ b/src/opt/maxsmt.h
@@ -33,7 +33,7 @@ namespace opt {
 
     typedef vector<rational> const weights_t;
 
-    class context;
+    class maxsat_context;
 
     class maxsmt_solver {
     protected:
@@ -59,7 +59,7 @@ namespace opt {
     class maxsmt_solver_base : public maxsmt_solver {
     protected:
         ast_manager&     m;
-        context&         m_c;
+        maxsat_context&  m_c;
         volatile bool    m_cancel;
         const expr_ref_vector  m_soft;
         vector<rational> m_weights;
@@ -71,7 +71,7 @@ namespace opt {
         params_ref       m_params;           // config
 
     public:
-        maxsmt_solver_base(context& c, weights_t& ws, expr_ref_vector const& soft); 
+        maxsmt_solver_base(maxsat_context& c, weights_t& ws, expr_ref_vector const& soft); 
 
         virtual ~maxsmt_solver_base() {}        
         virtual rational get_lower() const { return m_lower; }
@@ -114,7 +114,7 @@ namespace opt {
 
     class maxsmt {
         ast_manager&              m;
-        context&                  m_c;
+        maxsat_context&           m_c;
         scoped_ptr<maxsmt_solver_base> m_msolver;
         volatile bool    m_cancel;
         expr_ref_vector  m_soft_constraints;
@@ -126,7 +126,7 @@ namespace opt {
         model_ref        m_model;
         params_ref       m_params;
     public:
-        maxsmt(context& c);
+        maxsmt(maxsat_context& c);
         lbool operator()();
         void set_cancel(bool f);
         void updt_params(params_ref& p);
diff --git a/src/opt/opt_context.h b/src/opt/opt_context.h
index 2284f427b..3b764aaf5 100644
--- a/src/opt/opt_context.h
+++ b/src/opt/opt_context.h
@@ -34,8 +34,40 @@ namespace opt {
 
     class opt_solver;
 
+    /**
+       \brief base class required by MaxSMT solvers.
+       By implementing a base class, you can invoke the MaxSMT solvers
+       independent of the overall optimization infrastructure.
+       The caller has to supply a solver object that encapsulates 
+       an incremental SAT or SMT solver. The MaxSMT solvers may assume that
+       the solver object should be in a satisfiable state and contain an initial model.
+    */
 
-    class context : public opt_wrapper, public pareto_callback {
+    class maxsat_context {
+    public:        
+        virtual filter_model_converter& fm() = 0;   // converter that removes fresh names introduced by simplification.
+        virtual bool sat_enabled() const = 0;       // is using th SAT solver core enabled?
+        virtual solver& get_solver() = 0;           // retrieve solver object (SAT or SMT solver)
+        virtual ast_manager& get_manager() = 0;      
+        virtual params_ref& params() = 0;
+        virtual void enable_sls(expr_ref_vector const& soft, weights_t& weights) = 0; // stochastic local search 
+        virtual void set_enable_sls(bool f) = 0;    // overwrite whether SLS is enabled.
+        virtual void set_soft_assumptions() = 0;    // configure SAT solver to skip assumptions assigned by unit-propagation  
+        virtual symbol const& maxsat_engine() const = 0; // retrieve maxsat engine configuration parameter.
+        virtual void get_base_model(model_ref& _m) = 0;  // retrieve model from initial satisfiability call.
+        virtual smt::context& smt_context() = 0;    // access SMT context for SMT based MaxSMT solver (wmax requires SMT core)
+    };
+
+    /**
+       \brief main context object for optimization.
+       Hard and soft assertions, and objectives are registered with this context.
+       It handles combinations of objectives.
+    */
+
+    class context : 
+        public opt_wrapper, 
+        public pareto_callback,
+        public maxsat_context {
         struct free_func_visitor;
         typedef map<symbol, maxsmt*, symbol_hash_proc, symbol_eq_proc> map_t;
         typedef map<symbol, unsigned, symbol_hash_proc, symbol_eq_proc> map_id;
@@ -176,17 +208,17 @@ namespace opt {
         virtual expr_ref mk_ge(unsigned i, model_ref& model);
         virtual expr_ref mk_le(unsigned i, model_ref& model);
 
-        smt::context& smt_context() { return m_opt_solver->get_context(); }
-        filter_model_converter& fm() { return m_fm; }
-        bool sat_enabled() const { return 0 != m_sat_solver.get(); }
-        solver& get_solver();
-        ast_manager& get_manager() { return this->m; }
-        params_ref& params() { return m_params; }
-        void enable_sls(expr_ref_vector const& soft, weights_t& weights);
-        void set_enable_sls(bool f) { m_enable_sls = f; }
-        void set_soft_assumptions();
-        symbol const& maxsat_engine() const { return m_maxsat_engine; }
-        void get_base_model(model_ref& _m);
+        virtual smt::context& smt_context() { return m_opt_solver->get_context(); }
+        virtual filter_model_converter& fm() { return m_fm; }
+        virtual bool sat_enabled() const { return 0 != m_sat_solver.get(); }
+        virtual solver& get_solver();
+        virtual ast_manager& get_manager() { return this->m; }
+        virtual params_ref& params() { return m_params; }
+        virtual void enable_sls(expr_ref_vector const& soft, weights_t& weights);
+        virtual void set_enable_sls(bool f) { m_enable_sls = f; }
+        virtual void set_soft_assumptions();
+        virtual symbol const& maxsat_engine() const { return m_maxsat_engine; }
+        virtual void get_base_model(model_ref& _m);
 
 
     private:
diff --git a/src/opt/wmax.cpp b/src/opt/wmax.cpp
index 48d46a6c9..5f7f76f25 100644
--- a/src/opt/wmax.cpp
+++ b/src/opt/wmax.cpp
@@ -33,7 +33,7 @@ namespace opt {
 
     class wmax : public maxsmt_solver_base {
     public:
-        wmax(context& c, weights_t& ws, expr_ref_vector const& soft): 
+        wmax(maxsat_context& c, weights_t& ws, expr_ref_vector const& soft): 
             maxsmt_solver_base(c, ws, soft) {}
         virtual ~wmax() {}
 
@@ -76,7 +76,7 @@ namespace opt {
         }
     };
 
-    maxsmt_solver_base* mk_wmax(context& c, weights_t& ws, expr_ref_vector const& soft) {
+    maxsmt_solver_base* mk_wmax(maxsat_context& c, weights_t& ws, expr_ref_vector const& soft) {
         return alloc(wmax, c, ws, soft);
     }
 
diff --git a/src/opt/wmax.h b/src/opt/wmax.h
index bb1be1b4e..9d44c88cf 100644
--- a/src/opt/wmax.h
+++ b/src/opt/wmax.h
@@ -23,7 +23,7 @@ Notes:
 #include "maxsmt.h"
 
 namespace opt {
-    maxsmt_solver_base* mk_wmax(context& c, weights_t & ws, expr_ref_vector const& soft);
+    maxsmt_solver_base* mk_wmax(maxsat_context& c, weights_t & ws, expr_ref_vector const& soft);
 
 }
 #endif
diff --git a/src/smt/smt_conflict_resolution.cpp b/src/smt/smt_conflict_resolution.cpp
index 1e5b4b81f..a68d4d820 100644
--- a/src/smt/smt_conflict_resolution.cpp
+++ b/src/smt/smt_conflict_resolution.cpp
@@ -372,7 +372,7 @@ namespace smt {
               tout << "js.kind: " << js.get_kind() << "\n";
               tout << "consequent: " << consequent << "\n";
 	      for (unsigned i = 0; i < m_assigned_literals.size(); ++i) {
-		tout << m_assigned_literals[i] << " ";
+                  tout << m_assigned_literals[i] << " ";
 	      }
 	      tout << "\n";
 	      );