diff --git a/src/command_line.cc b/src/command_line.cc
index 5178a6dc..8db61165 100644
--- a/src/command_line.cc
+++ b/src/command_line.cc
@@ -383,6 +383,8 @@ void LanguageServerMain(const std::string& bin_name,
 // MAIN ////////////////////////////////////////////////////////////////////////
 ////////////////////////////////////////////////////////////////////////////////
 int main(int argc, char** argv) {
+  TraceMe();
+
   std::unordered_map<std::string, std::string> options =
       ParseOptions(argc, argv);
 
diff --git a/src/platform.h b/src/platform.h
index a2c0fd34..bf55128c 100644
--- a/src/platform.h
+++ b/src/platform.h
@@ -47,4 +47,6 @@ std::vector<std::string> GetPlatformClangArguments();
 void FreeUnusedMemory();
 
 // If true objective-c index tests will be run.
-bool RunObjectiveCIndexTests();
\ No newline at end of file
+bool RunObjectiveCIndexTests();
+
+void TraceMe();
diff --git a/src/platform_posix.cc b/src/platform_posix.cc
index a38e7ef1..d0d0c603 100644
--- a/src/platform_posix.cc
+++ b/src/platform_posix.cc
@@ -37,8 +37,11 @@
 #if defined(__FreeBSD__)
 #include <sys/param.h>   // MAXPATHLEN
 #include <sys/sysctl.h>  // sysctl
+#elif defined(__APPLE__) || defined(__BSD__)
+#include <sys/ptrace.h>
 #elif defined(__linux__)
 #include <malloc.h>
+#include <sys/ptrace.h>
 #endif
 
 #include <iostream>
@@ -272,4 +275,12 @@ bool RunObjectiveCIndexTests() {
 #endif
 }
 
+void TraceMe() {
+  // If the environment variable is defined, wait for a debugger.
+  // In gdb, you need to invoke `signal SIGCONT` if you want cquery to continue
+  // after detaching.
+  if (getenv("CQUERY_TRACEME"))
+    raise(SIGTSTP);
+}
+
 #endif
diff --git a/src/platform_win.cc b/src/platform_win.cc
index 88370a58..b61aa0fe 100644
--- a/src/platform_win.cc
+++ b/src/platform_win.cc
@@ -146,4 +146,8 @@ bool RunObjectiveCIndexTests() {
   return false;
 }
 
+// TODO Wait for debugger to attach
+void TraceMe() {
+}
+
 #endif