Do not fork services from the zygote on macOS

app/env.py

@@ -3,10 +3,14 @@
 """
 
 import argparse
+import sys
 import textwrap
 
+from ..log import make_log
 from .config import load_config
 
+log = make_log("baselayer")
+
 # Cache loading of environment
 _cache = {}
 
@@ -41,6 +45,10 @@ def load_env(load_services_configs=True):
         cfg = load_config(
             config_files=env.config or [], load_services_configs=load_services_configs
         )
+        # macOS system libraries crash in a child forked without exec
+        if sys.platform == "darwin" and cfg["zygote.services"]:
+            cfg["zygote"]["services"] = []
+            log("Not forking services from the zygote on macOS")
 
         _cache.update({"file": env.config, "env": env, "cfg": cfg})
 

config.yaml.defaults

@@ -142,7 +142,8 @@ services:
 
 zygote:
   # Services (directory names, or '*') whose Python processes are forked from
-  # the zygote, which imports `preload` once so they share those modules
+  # the zygote, which imports `preload` once so they share those modules.
+  # Ignored on macOS, where services are always started on their own.
   services: []
   # Services to leave out, e.g. when `services` is '*'
   exclude: []