Now database support is disable dby default, and can be enabled by passing databases=yes to the engine's build script.

SConstruct

@@ -80,6 +80,7 @@ opts.Add(EnumVariable("target", "Compilation target", "debug", ("debug", "releas
 opts.Add("folders", "App folders to compile", "")
 opts.Add("main_file", "The main file", "")
 opts.Add("module_folders", "App module folders to compile", "")
+opts.Add("databases", "Whether to have database support", False)
 
 # Compilation environment setup
 opts.Add("CXX", "C++ compiler")
@@ -110,9 +111,11 @@ scons_ver = env_base._get_major_minor_revision(scons_raw_version)
 if scons_ver >= (4, 0, 0):
     env_base.Tool("compilation_db")
 
-
 database_list = []
 
+if env_base["databases"]:
+    env_base.Append(CPPDEFINES=["DATABASES_ENABLED"])
+
     for x in sorted(glob.glob("database/*")):
         if not os.path.isdir(x) or not os.path.exists(x + "/detect.py"):
             continue
@@ -177,6 +180,7 @@ Export("env")
 
 SConscript("core/SCsub")
 
+if env_base["databases"]:
     for d in database_list:
         tmppath = "./database/" + d
         sys.path.insert(0, tmppath)

modules/drogon/detect.py

@@ -62,6 +62,11 @@ def configure(env):
     if not err:
         env.ParseConfig("pkg-config libcares --cflags --libs")
 
+    err = os.system("pkg-config zlib --modversion --silence-errors > /dev/null ")
+
+    if not err:
+        env.ParseConfig("pkg-config zlib --cflags --libs")
+
     err = os.system("pkg-config openssl --modversion --silence-errors > /dev/null ")
     
     if not err:
@@ -76,3 +81,5 @@ def configure(env):
     env.Prepend(CPPPATH=["#modules/drogon/trantor/net/inner"])
     env.Prepend(CPPPATH=["#modules/drogon/trantor/utils"])
 
+    env.Append(LINKFLAGS=["-ldl"])
+