diff --git a/repos/base-hw/lib/mk/core-hw.inc b/repos/base-hw/lib/mk/core-hw.inc
index a875b20eb8..98657c1581 100644
--- a/repos/base-hw/lib/mk/core-hw.inc
+++ b/repos/base-hw/lib/mk/core-hw.inc
@@ -58,7 +58,6 @@ SRC_CC += kernel/object.cc
 SRC_CC += kernel/signal_receiver.cc
 SRC_CC += kernel/thread.cc
 SRC_CC += kernel/timer.cc
-SRC_CC += init_main_thread.cc
 SRC_CC += capability.cc
 SRC_CC += stack_area_addr.cc
 SRC_CC += heartbeat.cc
diff --git a/repos/base-hw/recipes/src/base-hw_content.inc b/repos/base-hw/recipes/src/base-hw_content.inc
index 38ab511db0..84f8e3a367 100644
--- a/repos/base-hw/recipes/src/base-hw_content.inc
+++ b/repos/base-hw/recipes/src/base-hw_content.inc
@@ -121,7 +121,7 @@ SRC_LIB_TIMEOUT += duration.cc \
                    timer_connection.cc \
                    timer_connection_time.cc
 
-SRC_LIB_STARTUP += init_main_thread.cc _main.cc \
+SRC_LIB_STARTUP += _main.cc \
                    $(addprefix spec/,${call selected_content,SRC_LIB_STARTUP_SPECS})
 
 SRC_CORE += $(notdir $(wildcard $(BASE_HW_DIR)/src/core/*.cc)) \
diff --git a/repos/base/lib/mk/startup.inc b/repos/base/lib/mk/startup.inc
index f76e595c25..f9d1b874d4 100644
--- a/repos/base/lib/mk/startup.inc
+++ b/repos/base/lib/mk/startup.inc
@@ -1,5 +1,5 @@
 SRC_S       += crt0.s
-SRC_CC      += _main.cc init_main_thread.cc
+SRC_CC      += _main.cc
 REP_INC_DIR += src/include
 
 vpath %.cc $(BASE_DIR)/src/lib/startup
diff --git a/repos/base/src/lib/startup/_main.cc b/repos/base/src/lib/startup/_main.cc
index ca6baf6a5c..09d72a5acf 100644
--- a/repos/base/src/lib/startup/_main.cc
+++ b/repos/base/src/lib/startup/_main.cc
@@ -4,28 +4,117 @@
  * \author  Christian Prochaska
  * \author  Norman Feske
  * \date    2006-04-12
- *
- * The startup code calls constructors for static objects before calling
- * main(). Furthermore, this file contains the support of exit handlers
- * and destructors.
  */
 
 /*
- * Copyright (C) 2006-2017 Genode Labs GmbH
+ * Copyright (C) 2006-2023 Genode Labs GmbH
  *
  * This file is part of the Genode OS framework, which is distributed
  * under the terms of the GNU Affero General Public License version 3.
  */
 
 /* Genode includes */
-#include <base/env.h>
 #include <base/sleep.h>
+#include <base/thread.h>
 #include <base/component.h>
 
 /* platform-specific local helper functions */
-#include <base/internal/parent_cap.h>
+#include <base/internal/globals.h>
 #include <base/internal/crt0.h>
 
+using namespace Genode;
+
+
+addr_t init_main_thread_result;
+
+enum { MAIN_THREAD_STACK_SIZE = 16*1024 };
+
+
+/**
+ * Satisfy crt0.s in static programs, LDSO overrides this symbol
+ */
+extern "C" void init_rtld() __attribute__((weak));
+void init_rtld()
+{
+	/* init cxa guard mechanism before any local static variables are used */
+	init_cxx_guard();
+}
+
+
+/**
+ * Lower bound of the stack, solely used for sanity checking
+ */
+extern unsigned char __initial_stack_base[];
+
+
+/**
+ * The first thread in a program
+ */
+struct Main_thread : Thread
+{
+	Main_thread()
+	:
+		Thread(Weight::DEFAULT_WEIGHT, "main", MAIN_THREAD_STACK_SIZE, Type::MAIN)
+	{ }
+
+	/**********************
+	 ** Thread interface **
+	 **********************/
+
+	void entry() override { }
+};
+
+
+Main_thread * main_thread()
+{
+	static Main_thread s { };
+	return &s;
+}
+
+
+/**
+ * Create a thread object for the main thread
+ *
+ * \return  stack pointer of the new environment via init_main_thread_result
+ *
+ * This function must be called only once per program and before the _main
+ * function. It can be called as soon as a temporary environment provides
+ * some stack space and inter-process communication. At this stage, global
+ * static objects are not registered for implicit destruction at program exit.
+ */
+extern "C" void init_main_thread()
+{
+	prepare_init_main_thread();
+
+	init_platform();
+
+	/* create a thread object for the main thread */
+	main_thread();
+
+	/**
+	 * The new stack pointer enables the caller to switch from its current
+	 * environment to the those that the thread object provides.
+	 */
+	addr_t const sp = reinterpret_cast<addr_t>(main_thread()->stack_top());
+	init_main_thread_result = sp;
+
+	/*
+	 * Sanity check for the usage of the initial stack
+	 *
+	 * Because the initial stack is located in the BSS, it is zero-initialized.
+	 * We check that the stack still contains zeros at its lower boundary after
+	 * executing all the initialization code.
+	 */
+	enum { STACK_PAD = 256U };
+	for (unsigned i = 0; i < STACK_PAD; i++) {
+		if (__initial_stack_base[i] == 0)
+			continue;
+
+		error("initial stack overflow detected");
+		for (;;);
+	}
+}
+
 void * __dso_handle = 0;
 
 
@@ -47,11 +136,6 @@ int    genode_argc = 1;
 char **genode_envp = 0;
 
 
-/******************************************************
- ** C entry function called by the crt0 startup code **
- ******************************************************/
-
-
 namespace Genode {
 
 	/*
diff --git a/repos/base/src/lib/startup/init_main_thread.cc b/repos/base/src/lib/startup/init_main_thread.cc
deleted file mode 100644
index a3d6f954ff..0000000000
--- a/repos/base/src/lib/startup/init_main_thread.cc
+++ /dev/null
@@ -1,117 +0,0 @@
-/*
- * \brief  Setup the thread environment of a programs first thread
- * \author Christian Helmuth
- * \author Christian Prochaska
- * \author Martin Stein
- * \date   2013-12-04
- */
-
-/*
- * Copyright (C) 2013-2017 Genode Labs GmbH
- *
- * This file is part of the Genode OS framework, which is distributed
- * under the terms of the GNU Affero General Public License version 3.
- */
-
-/* Genode includes */
-#include <util/construct_at.h>
-#include <base/env.h>
-#include <base/thread.h>
-
-/* base-internal includes */
-#include <base/internal/globals.h>
-
-using namespace Genode;
-
-
-addr_t init_main_thread_result;
-
-namespace Genode { extern Region_map * env_stack_area_region_map; }
-
-enum { MAIN_THREAD_STACK_SIZE = 16*1024 };
-
-
-/**
- * Satisfy crt0.s in static programs, LDSO overrides this symbol
- */
-extern "C" void init_rtld() __attribute__((weak));
-void init_rtld()
-{
-	/* init cxa guard mechanism before any local static variables are used */
-	init_cxx_guard();
-}
-
-
-/**
- * Lower bound of the stack, solely used for sanity checking
- */
-extern unsigned char __initial_stack_base[];
-
-
-/**
- * The first thread in a program
- */
-struct Main_thread : Thread
-{
-	Main_thread()
-	:
-		Thread(Weight::DEFAULT_WEIGHT, "main", MAIN_THREAD_STACK_SIZE, Type::MAIN)
-	{ }
-
-	/**********************
-	 ** Thread interface **
-	 **********************/
-
-	void entry() override { }
-};
-
-
-Main_thread * main_thread()
-{
-	static Main_thread s { };
-	return &s;
-}
-
-
-/**
- * Create a thread object for the main thread
- *
- * \return  stack pointer of the new environment via init_main_thread_result
- *
- * This function must be called only once per program and before the _main
- * function. It can be called as soon as a temporary environment provides
- * some stack space and inter-process communication. At this stage, global
- * static objects are not registered for implicit destruction at program exit.
- */
-extern "C" void init_main_thread()
-{
-	prepare_init_main_thread();
-
-	init_platform();
-
-	/* create a thread object for the main thread */
-	main_thread();
-
-	/**
-	 * The new stack pointer enables the caller to switch from its current
-	 * environment to the those that the thread object provides.
-	 */
-	addr_t const sp = reinterpret_cast<addr_t>(main_thread()->stack_top());
-	init_main_thread_result = sp;
-
-	/*
-	 * Sanity check for the usage of the initial stack
-	 *
-	 * Because the initial stack is located in the BSS, it is zero-initialized.
-	 * We check that the stack still contains zeros at its lower boundary after
-	 * executing all the initialization code.
-	 */
-	enum { STACK_PAD = 256U };
-	for (unsigned i = 0; i < STACK_PAD; i++) {
-		if (__initial_stack_base[i] == 0)
-			continue;
-
-		error("initial stack overflow detected");
-		for (;;);
-	}
-}