diff --git a/gtsam/discrete/discrete.i b/gtsam/discrete/discrete.i
index 93979bba17..b3a12a8d52 100644
--- a/gtsam/discrete/discrete.i
+++ b/gtsam/discrete/discrete.i
@@ -70,7 +70,7 @@ virtual class DecisionTreeFactor : gtsam::DiscreteFactor {
   string dot(
       const gtsam::KeyFormatter& keyFormatter = gtsam::DefaultKeyFormatter,
       bool showZero = true) const;
-  std::vector<std::pair<DiscreteValues, double>> enumerate() const;
+  std::vector<std::pair<gtsam::DiscreteValues, double>> enumerate() const;
   string markdown(const gtsam::KeyFormatter& keyFormatter =
                       gtsam::DefaultKeyFormatter) const;
   string markdown(const gtsam::KeyFormatter& keyFormatter,
@@ -97,7 +97,7 @@ virtual class DiscreteConditional : gtsam::DecisionTreeFactor {
                       const gtsam::Ordering& orderedKeys);
   gtsam::DiscreteConditional operator*(
       const gtsam::DiscreteConditional& other) const;
-  DiscreteConditional marginal(gtsam::Key key) const;
+  gtsam::DiscreteConditional marginal(gtsam::Key key) const;
   void print(string s = "Discrete Conditional\n",
              const gtsam::KeyFormatter& keyFormatter =
                  gtsam::DefaultKeyFormatter) const;
@@ -269,16 +269,16 @@ class DiscreteFactorGraph {
   gtsam::DiscreteLookupDAG maxProduct(gtsam::Ordering::OrderingType type);
   gtsam::DiscreteLookupDAG maxProduct(const gtsam::Ordering& ordering);
 
-  gtsam::DiscreteBayesNet eliminateSequential();
-  gtsam::DiscreteBayesNet eliminateSequential(gtsam::Ordering::OrderingType type);
-  gtsam::DiscreteBayesNet eliminateSequential(const gtsam::Ordering& ordering);
-  std::pair<gtsam::DiscreteBayesNet, gtsam::DiscreteFactorGraph>
+  gtsam::DiscreteBayesNet* eliminateSequential();
+  gtsam::DiscreteBayesNet* eliminateSequential(gtsam::Ordering::OrderingType type);
+  gtsam::DiscreteBayesNet* eliminateSequential(const gtsam::Ordering& ordering);
+  pair<gtsam::DiscreteBayesNet*, gtsam::DiscreteFactorGraph*>
       eliminatePartialSequential(const gtsam::Ordering& ordering);
 
-  gtsam::DiscreteBayesTree eliminateMultifrontal();
-  gtsam::DiscreteBayesTree eliminateMultifrontal(gtsam::Ordering::OrderingType type);  
-  gtsam::DiscreteBayesTree eliminateMultifrontal(const gtsam::Ordering& ordering);  
-  std::pair<gtsam::DiscreteBayesTree, gtsam::DiscreteFactorGraph>
+  gtsam::DiscreteBayesTree* eliminateMultifrontal();
+  gtsam::DiscreteBayesTree* eliminateMultifrontal(gtsam::Ordering::OrderingType type);  
+  gtsam::DiscreteBayesTree* eliminateMultifrontal(const gtsam::Ordering& ordering);  
+  pair<gtsam::DiscreteBayesTree*, gtsam::DiscreteFactorGraph*>
       eliminatePartialMultifrontal(const gtsam::Ordering& ordering);
 
   string dot(
diff --git a/gtsam/slam/slam.i b/gtsam/slam/slam.i
index 2785a3fb3d..4e943253ea 100644
--- a/gtsam/slam/slam.i
+++ b/gtsam/slam/slam.i
@@ -223,12 +223,12 @@ enum KernelFunctionType {
   KernelFunctionTypeTUKEY
 };
 
-std::pair<gtsam::NonlinearFactorGraph*, gtsam::Values*> load2D(
+pair<gtsam::NonlinearFactorGraph*, gtsam::Values*> load2D(
     string filename, gtsam::noiseModel::Diagonal* model = nullptr,
     size_t maxIndex = 0, bool addNoise = false, bool smart = true,
-    gtsam::NoiseFormat noiseFormat = gtsam::NoiseFormatAUTO,
+    gtsam::NoiseFormat noiseFormat = gtsam::NoiseFormat::NoiseFormatAUTO,
     gtsam::KernelFunctionType kernelFunctionType =
-        gtsam::KernelFunctionTypeNONE);
+        gtsam::KernelFunctionType::KernelFunctionTypeNONE);
 
 void save2D(const gtsam::NonlinearFactorGraph& graph,
             const gtsam::Values& config, gtsam::noiseModel::Diagonal* model,
@@ -259,7 +259,7 @@ pair<gtsam::NonlinearFactorGraph*, gtsam::Values*> load3D(string filename);
 pair<gtsam::NonlinearFactorGraph*, gtsam::Values*> readG2o(
     string filename, const bool is3D = false,
     gtsam::KernelFunctionType kernelFunctionType =
-        gtsam::KernelFunctionTypeNONE);
+        gtsam::KernelFunctionType::KernelFunctionTypeNONE);
 void writeG2o(const gtsam::NonlinearFactorGraph& graph,
               const gtsam::Values& estimate, string filename);
 
diff --git a/matlab/CMakeLists.txt b/matlab/CMakeLists.txt
index 749ad870ac..1755e2075e 100644
--- a/matlab/CMakeLists.txt
+++ b/matlab/CMakeLists.txt
@@ -68,6 +68,8 @@ set(interface_files
     ${GTSAM_SOURCE_DIR}/gtsam/gtsam.i
     ${GTSAM_SOURCE_DIR}/gtsam/base/base.i
     ${GTSAM_SOURCE_DIR}/gtsam/basis/basis.i
+    ${PROJECT_SOURCE_DIR}/gtsam/inference/inference.i
+    ${PROJECT_SOURCE_DIR}/gtsam/discrete/discrete.i
     ${GTSAM_SOURCE_DIR}/gtsam/geometry/geometry.i
     ${GTSAM_SOURCE_DIR}/gtsam/linear/linear.i
     ${GTSAM_SOURCE_DIR}/gtsam/nonlinear/nonlinear.i
diff --git a/python/gtsam/preamble/inference.h b/python/gtsam/preamble/inference.h
index 320e0ac718..d07a75f6fb 100644
--- a/python/gtsam/preamble/inference.h
+++ b/python/gtsam/preamble/inference.h
@@ -10,6 +10,3 @@
  * Without this they will be automatically converted to a Python object, and all
  * mutations on Python side will not be reflected on C++.
  */
-
-#include <pybind11/stl.h>
-