diff --git a/.gitignore b/.gitignore
index f606d26..fa039f6 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,8 @@
+*.json
+!sample_ast.json
+*.o
+*.pch
+*.gch
 a.out.*
 *.log
 *.pyc
diff --git a/Makefile b/Makefile
index 4eda0dc..fcea7cc 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,7 @@
 OS_SUPPORT = 
 MonetDB_LIB = 
 Threading = 
+
 ifeq ($(OS),Windows_NT)
 	OS_SUPPORT += server/winhelper.cpp
 	MonetDB_LIB += -Imonetdb/msvc msc-plugin/monetdbe.dll 
@@ -11,6 +12,7 @@ endif
 ifeq ($(THREADING),1)
 	Threading += server/threading.cpp -DTHREADING
 endif
+
 info:
 	$(info $(OS_SUPPORT))
 	$(info $(OS)) 
@@ -22,6 +24,6 @@ server.so:
 #	$(CXX) server/server.cpp server/monetdb_conn.cpp -fPIC -shared $(OS_SUPPORT) monetdb/msvc/monetdbe.dll --std=c++1z -O3 -march=native -o server.so -I./monetdb/msvc 
 	$(CXX) -shared -fPIC -flto server/server.cpp server/io.cpp server/table.cpp $(OS_SUPPORT) server/monetdb_conn.cpp $(Threading) $(MonetDB_LIB)  --std=c++1z -o server.so -O3
 snippet:
-	$(CXX) -shared -fPIC -flto --std=c++1z out.cpp server/monetdb_conn.cpp server/table.cpp server/io.cpp $(MonetDB_LIB) -O3 -march=native -o dll.so
+	$(CXX) -shared -fPIC -flto --std=c++1z -include server/aggregations.h out.cpp server/monetdb_conn.cpp server/table.cpp server/io.cpp $(MonetDB_LIB) -O3 -march=native -o dll.so
 clean:
 	rm *.shm -rf
diff --git a/prompt.py b/prompt.py
index 348b8bb..bf47811 100644
--- a/prompt.py
+++ b/prompt.py
@@ -104,7 +104,7 @@ class PromptState():
     th = None
     send = None
     test_parser = True
-    server_mode : RunType = RunType.Threaded
+    server_mode: RunType = RunType.Threaded
     server_bin = 'server.bin' if server_mode == RunType.IPC else 'server.so'
     set_ready = lambda: None
     get_ready = lambda: None
@@ -381,6 +381,9 @@ def main(running = lambda:True, next = input, state = None):
             print(e)
         except (KeyboardInterrupt):
             break
+        except SystemExit:
+            print("\nBye.")
+            raise
         except:
             import code, traceback
             sh = code.InteractiveConsole({**globals(), **locals()})
diff --git a/reconstruct/ast.py b/reconstruct/ast.py
index 5b248e6..0061ec7 100644
--- a/reconstruct/ast.py
+++ b/reconstruct/ast.py
@@ -30,10 +30,10 @@ class ast_node:
     def add(self, code):
         self.sql += code + ' '
     def addc(self, code):
-        self.ccode += code + '\n'  
-         
+        self.ccode += code + '\n'
+
     name = 'null'
-    
+
     def init(self, _):
         if self.parent is None:
             self.context.sql_begin()
@@ -43,7 +43,7 @@ class ast_node:
         pass
     def spawn(self, _):
         pass
-    
+
     def consume(self, _):
         if self.parent is None:
             self.emit(self.sql+';\n')
@@ -245,7 +245,7 @@ class projection(ast_node):
                 if type(val[1]) is int:
                     self.context.emitc(f'{self.outtable_name}->get_col<{key}>().initfrom({vid2cname[val[1]]});')
                 else:
-            # for funcs evaluate f_i(x, ...)
+                    # for funcs evaluate f_i(x, ...)
                     self.context.emitc(f'{self.outtable_name}->get_col<{key}>() = {val[1]};')
         # print out col_is
         self.context.emitc(f'print(*{self.outtable_name});')
diff --git a/server/monetdb_conn.cpp b/server/monetdb_conn.cpp
index 0cfc911..61428d8 100644
--- a/server/monetdb_conn.cpp
+++ b/server/monetdb_conn.cpp
@@ -139,4 +139,12 @@ void* Server::getCol(int col_idx){
 
 Server::~Server(){
     close();
-}
\ No newline at end of file
+}
+
+bool Server::havehge() {
+#if defined(_MONETDBE_LIB_) and defined(HAVE_HGE)
+    return HAVE_HGE;
+#else
+    return false;
+#endif
+}
diff --git a/server/monetdb_conn.h b/server/monetdb_conn.h
index b550476..5afae0e 100644
--- a/server/monetdb_conn.h
+++ b/server/monetdb_conn.h
@@ -1,3 +1,5 @@
+#ifndef __MONETDB_CONN_H__
+#define __MONETDB_CONN_H__
 
 struct Context;
 
@@ -19,5 +21,8 @@ struct Server{
     void *getCol(int col_idx);
     void close();
     bool haserror();
+    static bool havehge();
     ~Server();
 };
+
+#endif
diff --git a/server/server.cpp b/server/server.cpp
index 522df1f..3c4003f 100644
--- a/server/server.cpp
+++ b/server/server.cpp
@@ -65,8 +65,8 @@ extern "C" int __DLLEXPORT__ binary_info() {
 }
 
 __AQEXPORT__(bool) have_hge(){
-#if  defined(_MONETDBE_LIB_) and defined(HAVE_HGE)
-    return HAVE_HGE;
+#if defined(__MONETDB_CONN_H__)
+    return Server::havehge();
 #else
     return false;
 #endif
@@ -105,10 +105,10 @@ int dll_main(int argc, char** argv, Context* cxt){
                     }
                     for(int i = 0; i < n_recv; ++i)
                     {
-                        printf("%s, %d\n", n_recvd[i], n_recvd[i][0] == 'Q');
+                        //printf("%s, %d\n", n_recvd[i], n_recvd[i][0] == 'Q');
                         if (n_recvd[i][0] == 'Q'){
                             server->exec(n_recvd[i] + 1);
-                            printf("Exec Q%d: %s\n", i, n_recvd[i]);
+                            printf("Exec Q%d: %s", i, n_recvd[i]);
                         }
                         else if (n_recvd[i][0] == 'P' && handle && !server->haserror()) {
                             code_snippet c = reinterpret_cast<code_snippet>(dlsym(handle, n_recvd[i]+1));
diff --git a/server/types.h b/server/types.h
index 1df357f..562a0c4 100644
--- a/server/types.h
+++ b/server/types.h
@@ -1,10 +1,10 @@
 #ifndef _TYPES_H
 #define _TYPES_H
 #include <typeinfo>
-#include <functional>
 #include <cstdint>
 #include <type_traits>
 #include <string>
+#include <tuple>
 
 #ifdef _MSC_VER
 #define __restrict__ __restrict