diff --git a/README.md b/README.md
index 8d8ed22..15ae6a6 100644
--- a/README.md
+++ b/README.md
@@ -22,20 +22,6 @@ libstdc++.so.6: version `GLIBCXX_3.4.32' not found (required by b_xxxx)
 
 The solution is to erase the libstdc++ library from the miniconda installation:
 
-### MPI
-
-In Linux just install openmpi & openmpi-devel packages. Only if cmake can't find openmpi installation (like in Oracle Linux) set the following variable:
-
-```bash
-export MPI_HOME="/usr/lib64/openmpi"
-```
-
-In Mac OS X, install mpich with brew and if cmake doesn't find it, edit mpicxx wrapper to remove the ",-commons,use_dylibs" from final_ldflags
-
-```bash
-vi /opt/homebrew/bin/mpicx
-```
-
 ### boost library
 
 [Getting Started](<https://www.boost.org/doc/libs/1_83_0/more/getting_started/index.html>)
diff --git a/lib/catch2 b/lib/catch2
index 8ac8190..cd8f97e 160000
--- a/lib/catch2
+++ b/lib/catch2
@@ -1 +1 @@
-Subproject commit 8ac8190e494a381072c89f5e161b92a08d98b37b
+Subproject commit cd8f97e6c7f6aaf332992f83bf9d7ee7f357f85e
diff --git a/lib/json b/lib/json
index 0457de2..377c767 160000
--- a/lib/json
+++ b/lib/json
@@ -1 +1 @@
-Subproject commit 0457de21cffb298c22b629e538036bfeb96130b7
+Subproject commit 377c767aa19da7159cf537490bc33da96edf8803
diff --git a/pyclfs/PyClassifier.h b/pyclfs/PyClassifier.h
index e972686..ffcdd7f 100644
--- a/pyclfs/PyClassifier.h
+++ b/pyclfs/PyClassifier.h
@@ -42,7 +42,7 @@ namespace pywrap {
         std::vector<std::string> graph(const std::string& title = "") const override { return std::vector<std::string>(); }
         bayesnet::status_t getStatus() const override { return bayesnet::NORMAL; };
         std::vector<std::string> topological_order() override { return std::vector<std::string>(); }
-        void dump_cpt() const override {};
+        std::string dump_cpt() const override { return ""; };
         std::vector<std::string> getNotes() const override { return notes; };
         void setHyperparameters(const nlohmann::json& hyperparameters) override;
     protected: