Here is an example python extension using code generation (synth_shed)

gen/examples/ext/synth_shed/Makefile

@@ -0,0 +1,38 @@
+include Makefile.conf
+
+TARGET_MODULE=synth_shed.so
+# C++
+CXX=clang
+CXXFLAGS+=-std=c++11 -g
+
+# Sources
+SRCS+=$(wildcard *.cc)
+OBJS+=$(SRCS:.cc=.o)
+
+#Compile
+CXXFLAGS+=$(INCLUDES) -I$(PREFIX)/include
+
+#Link
+LDFLAGS+=-undefined dynamic_lookup $(LIBS_PATH) $(LIBS)
+
+
+$(info -----BUILD INFO----)
+$(info SRCS 	$(SRCS))
+$(info OBJS 	$(OBJS))
+
+.PHONY: all gen module clean
+
+all: gen module
+
+gen:
+	$(MAKE) -C gen
+
+module: $(TARGET_MODULE)
+
+$(TARGET_MODULE) : $(OBJS)
+	$(CXX) $(LDFLAGS) -o $@ $^
+
+clean:
+	$(MAKE) -C gen clean
+	rm -f $(TARGET_MODULE)
+	rm -f $(OBJS)

gen/examples/ext/synth_shed/Makefile.conf

@@ -0,0 +1,18 @@
+# pyBind11
+PREFIX=/Users/heck/local-default
+
+# YML2
+YML2_PATH=$(HOME)/src/pepbase/default/yml2
+YML2_PROC=$(YML2_PATH)/yml2proc $(YML2_OPTS)
+YML2_OPTS=--encoding=utf8
+
+# GEN-CID
+GEN_CID_DIR=../../../../gen_cid/
+
+# C Python headers
+INCLUDES+=-I/opt/local/Library/Frameworks/Python.framework/Versions/3.8/include/python3.8
+
+# example lib
+INCLUDES+=-I../../lib/synth_shed
+LIBS+=-lsynth_shed
+LIBS_PATH+=-L../../lib/synth_shed/

gen/examples/synth_shed/Makefile → gen/examples/ext/synth_shed/gen/Makefile

@@ -1,9 +1,8 @@
-include Makefile.conf
+include ../Makefile.conf
 
 YML2_FILE=py_module.yml2
 CC_FILE=py_module.cc
 
-
 .PHONY = yml cc
 
 all: yml cc

gen/examples/synth_shed/config.json → gen/examples/ext/synth_shed/gen/config.json

@@ -1,6 +1,6 @@
 {
     "module_name": "synth_shed",
-    "header_filename": "../../src/synth_shed/synth_shed.h",
+    "header_filename": "../../../../examples/lib/synth_shed/synth_shed.h",
     "libclang_path": "/opt/local/libexec/llvm-9.0/lib/libclang.dylib",
     "variables": [
     ],

gen/examples/ext/synth_shed/synth_shed.cc

@@ -0,0 +1,14 @@
+#include <string>
+#include <iostream>
+#include <pybind11/pybind11.h>
+#include <pybind11/detail/common.h>
+#include "synth_shed.h"
+
+using namespace std;
+
+PYBIND11_MODULE(synth_shed, m) {
+    #include "gen/py_module.cc"
+
+
+}
+

gen/examples/synth_shed/Makefile.conf

@@ -1,5 +0,0 @@
-YML2_PATH=$(HOME)/src/pepbase/default/yml2
-YML2_PROC=$(YML2_PATH)/yml2proc $(YML2_OPTS)
-YML2_OPTS=--encoding=utf8
-
-GEN_CID_DIR=../../gen_cid/