diff --git a/src/analyze/analyze-security.c b/src/analyze/analyze-security.c
index e0d313dcec..ba544ba1e5 100644
--- a/src/analyze/analyze-security.c
+++ b/src/analyze/analyze-security.c
@@ -20,7 +20,6 @@
 #include "format-table.h"
 #include "in-addr-prefix-util.h"
 #include "manager.h"
-#include "missing_sched.h"
 #include "mkdir.h"
 #include "nulstr-util.h"
 #include "parse-util.h"
diff --git a/src/basic/argv-util.c b/src/basic/argv-util.c
index ab0fe3280d..214c4b61f9 100644
--- a/src/basic/argv-util.c
+++ b/src/basic/argv-util.c
@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
+#include <sched.h>
 #include <stdlib.h>
 #include <sys/mman.h>
 #include <sys/prctl.h>
@@ -8,7 +9,6 @@
 #include "capability-util.h"
 #include "errno-util.h"
 #include "log.h"
-#include "missing_sched.h"
 #include "parse-util.h"
 #include "path-util.h"
 #include "process-util.h"
diff --git a/src/basic/fd-util.c b/src/basic/fd-util.c
index 09a843c160..6493c83c48 100644
--- a/src/basic/fd-util.c
+++ b/src/basic/fd-util.c
@@ -16,7 +16,6 @@
 #include "format-util.h"
 #include "fs-util.h"
 #include "log.h"
-#include "missing_fcntl.h"
 #include "missing_syscall.h"
 #include "mountpoint-util.h"
 #include "parse-util.h"
@@ -971,7 +970,7 @@ int fd_verify_safe_flags_full(int fd, int extra_flags) {
          *             and since we refuse O_PATH it should be safe.
          *
          * RAW_O_LARGEFILE: glibc secretly sets this and neglects to hide it from us if we call fcntl.
-         *                  See comment in missing_fcntl.h for more details about this.
+         *                  See comment in src/basic/include/fcntl.h for more details about this.
          *
          * If 'extra_flags' is specified as non-zero the included flags are also allowed.
          */
diff --git a/src/basic/fd-util.h b/src/basic/fd-util.h
index c0b9c1b51c..7d5b9f3083 100644
--- a/src/basic/fd-util.h
+++ b/src/basic/fd-util.h
@@ -2,10 +2,10 @@
 #pragma once
 
 #include <dirent.h>
+#include <fcntl.h>
 #include <stdio.h>
 
 #include "forward.h"
-#include "missing_fcntl.h"
 
 /* maximum length of fdname */
 #define FDNAME_MAX 255
diff --git a/src/basic/fs-util.c b/src/basic/fs-util.c
index 4f9b52207f..3a3b09776a 100644
--- a/src/basic/fs-util.c
+++ b/src/basic/fs-util.c
@@ -16,7 +16,6 @@
 #include "label.h"
 #include "lock-util.h"
 #include "log.h"
-#include "missing_fcntl.h"
 #include "missing_syscall.h"
 #include "mkdir.h"
 #include "path-util.h"
diff --git a/src/basic/missing_fcntl.h b/src/basic/include/fcntl.h
similarity index 97%
rename from src/basic/missing_fcntl.h
rename to src/basic/include/fcntl.h
index 64f37f5ee8..86e0c8bbf5 100644
--- a/src/basic/missing_fcntl.h
+++ b/src/basic/include/fcntl.h
@@ -1,7 +1,7 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
-#include <fcntl.h> /* IWYU pragma: export */
+#include_next <fcntl.h>
 
 /* This is defined since glibc-2.41. */
 #ifndef F_DUPFD_QUERY
diff --git a/src/basic/missing_sched.h b/src/basic/include/sched.h
similarity index 84%
rename from src/basic/missing_sched.h
rename to src/basic/include/sched.h
index c14162be59..13eb8d059e 100644
--- a/src/basic/missing_sched.h
+++ b/src/basic/include/sched.h
@@ -5,23 +5,22 @@
  * to make struct sched_attr being defined.
  * Note, this must be included before sched.h, otherwise the headers conflict with each other. */
 #include <linux/sched/types.h>
-#include <sched.h>       /* IWYU pragma: export */
 
-#include "forward.h"
+#include_next <sched.h>
 
 /* 769071ac9f20b6a447410c7eaa55d1a5233ef40c (5.8),
  * defined in sched.h since glibc-2.36. */
 #ifndef CLONE_NEWTIME
 #  define CLONE_NEWTIME 0x00000080
 #else
-assert_cc(CLONE_NEWTIME == 0x00000080);
+_Static_assert(CLONE_NEWTIME == 0x00000080, "");
 #endif
 
 /* Not exposed yet. Defined at include/linux/sched.h */
 #ifndef PF_KTHREAD
 #  define PF_KTHREAD 0x00200000
 #else
-assert_cc(PF_KTHREAD == 0x00200000);
+_Static_assert(PF_KTHREAD == 0x00200000, "");
 #endif
 
 /* The maximum thread/process name length including trailing NUL byte. This mimics the kernel definition of
@@ -32,5 +31,5 @@ assert_cc(PF_KTHREAD == 0x00200000);
 #ifndef TASK_COMM_LEN
 #  define TASK_COMM_LEN 16
 #else
-assert_cc(TASK_COMM_LEN == 16);
+_Static_assert(TASK_COMM_LEN == 16, "");
 #endif
diff --git a/src/basic/missing_mman.h b/src/basic/include/sys/mman.h
similarity index 62%
rename from src/basic/missing_mman.h
rename to src/basic/include/sys/mman.h
index b3f79935fe..50b03bddf0 100644
--- a/src/basic/missing_mman.h
+++ b/src/basic/include/sys/mman.h
@@ -1,20 +1,18 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
-#include <sys/mman.h> /* IWYU pragma: export */
-
-#include "forward.h"
+#include_next <sys/mman.h>
 
 /* since glibc-2.38 */
 #ifndef MFD_NOEXEC_SEAL
 #  define MFD_NOEXEC_SEAL 0x0008U
 #else
-assert_cc(MFD_NOEXEC_SEAL == 0x0008U);
+_Static_assert(MFD_NOEXEC_SEAL == 0x0008U, "");
 #endif
 
 /* since glibc-2.38 */
 #ifndef MFD_EXEC
 #  define MFD_EXEC 0x0010U
 #else
-assert_cc(MFD_EXEC == 0x0010U);
+_Static_assert(MFD_EXEC == 0x0010U, "");
 #endif
diff --git a/src/basic/include/sys/mount.h b/src/basic/include/sys/mount.h
index 211a552d6a..3f42a61233 100644
--- a/src/basic/include/sys/mount.h
+++ b/src/basic/include/sys/mount.h
@@ -1,6 +1,7 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
+#include <fcntl.h>
 #include <features.h>
 #include <linux/fs.h>
 #include <linux/mount.h> /* IWYU pragma: export */
@@ -10,7 +11,6 @@
 #include <sys/syscall.h>
 #include <unistd.h>
 
-#include "missing_fcntl.h"
 #include "missing_syscall_def.h"
 
 /* Since glibc-2.37 (774058d72942249f71d74e7f2b639f77184160a6), sys/mount.h includes linux/mount.h, and
diff --git a/src/basic/missing_pidfd.h b/src/basic/include/sys/pidfd.h
similarity index 92%
rename from src/basic/missing_pidfd.h
rename to src/basic/include/sys/pidfd.h
index 968875e895..de13144524 100644
--- a/src/basic/missing_pidfd.h
+++ b/src/basic/include/sys/pidfd.h
@@ -2,15 +2,17 @@
 #pragma once
 
 #include <linux/types.h>
+#include <sys/ioctl.h>
+
+/* since glibc-2.36 */
 #if HAVE_PIDFD_OPEN
-#include <sys/pidfd.h> /* IWYU pragma: export */
+#include_next <sys/pidfd.h>
 #endif
 
+/* since glibc-2.41 */
 #ifndef PIDFS_IOCTL_MAGIC
 #  define PIDFS_IOCTL_MAGIC 0xFF
-#endif
 
-#ifndef PIDFD_GET_CGROUP_NAMESPACE
 #  define PIDFD_GET_CGROUP_NAMESPACE              _IO(PIDFS_IOCTL_MAGIC, 1)
 #  define PIDFD_GET_IPC_NAMESPACE                 _IO(PIDFS_IOCTL_MAGIC, 2)
 #  define PIDFD_GET_MNT_NAMESPACE                 _IO(PIDFS_IOCTL_MAGIC, 3)
@@ -23,6 +25,7 @@
 #  define PIDFD_GET_UTS_NAMESPACE                 _IO(PIDFS_IOCTL_MAGIC, 10)
 #endif
 
+/* defined in linux/pidfd.h */
 #ifndef PIDFD_GET_INFO
 struct pidfd_info {
         __u64 mask;
diff --git a/src/basic/missing_random.h b/src/basic/include/sys/random.h
similarity index 60%
rename from src/basic/missing_random.h
rename to src/basic/include/sys/random.h
index 61b8c11ed0..c0d1197aa5 100644
--- a/src/basic/missing_random.h
+++ b/src/basic/include/sys/random.h
@@ -1,13 +1,11 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
-#include <sys/random.h> /* IWYU pragma: export */
-
-#include "forward.h"
+#include_next <sys/random.h>
 
 /* Defined since glibc-2.32. */
 #ifndef GRND_INSECURE
 #  define GRND_INSECURE 0x0004
 #else
-assert_cc(GRND_INSECURE == 0x0004);
+_Static_assert(GRND_INSECURE == 0x0004, "");
 #endif
diff --git a/src/basic/missing_socket.h b/src/basic/include/sys/socket.h
similarity index 95%
rename from src/basic/missing_socket.h
rename to src/basic/include/sys/socket.h
index cc453d2396..02218b3be1 100644
--- a/src/basic/missing_socket.h
+++ b/src/basic/include/sys/socket.h
@@ -1,7 +1,7 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
-#include <sys/socket.h> /* IWYU pragma: export */
+#include_next <sys/socket.h>
 
 /* Supported since kernel v6.5 (5e2ff6704a275be009be8979af17c52361b79b89) */
 #ifndef SO_PASSPIDFD
diff --git a/src/basic/missing_wait.h b/src/basic/include/sys/wait.h
similarity index 58%
rename from src/basic/missing_wait.h
rename to src/basic/include/sys/wait.h
index 821df7a971..0981631cf6 100644
--- a/src/basic/missing_wait.h
+++ b/src/basic/include/sys/wait.h
@@ -1,13 +1,11 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
-#include <sys/wait.h> /* IWYU pragma: export */
-
-#include "forward.h"
+#include_next <sys/wait.h>
 
 /* since glibc-2.36 */
 #ifndef P_PIDFD
 #  define P_PIDFD 3
 #else
-assert_cc(P_PIDFD == 3);
+_Static_assert(P_PIDFD == 3, "");
 #endif
diff --git a/src/basic/memfd-util.c b/src/basic/memfd-util.c
index d3a1a8457e..3257c1b9dd 100644
--- a/src/basic/memfd-util.c
+++ b/src/basic/memfd-util.c
@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
+#include <sched.h>
 #include <stdio.h>
 #include <sys/prctl.h>
 #include <sys/stat.h>
@@ -9,8 +10,6 @@
 #include "errno-util.h"
 #include "fd-util.h"
 #include "memfd-util.h"
-#include "missing_mman.h"
-#include "missing_sched.h"
 #include "string-util.h"
 #include "utf8.h"
 
diff --git a/src/basic/memfd-util.h b/src/basic/memfd-util.h
index efa2f7c616..befe41ac43 100644
--- a/src/basic/memfd-util.h
+++ b/src/basic/memfd-util.h
@@ -1,6 +1,8 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
+#include <sys/mman.h>           /* IWYU pragma: export */
+
 #include "forward.h"
 
 int memfd_create_wrapper(const char *name, unsigned mode);
diff --git a/src/basic/meson.build b/src/basic/meson.build
index c6c8556371..7a67d11275 100644
--- a/src/basic/meson.build
+++ b/src/basic/meson.build
@@ -127,7 +127,7 @@ basic_sources += missing_syscall_def_h
 generate_af_list = find_program('generate-af-list.sh')
 af_list_txt = custom_target(
         output : 'af-list.txt',
-        command : [generate_af_list, cpp, files('missing_socket.h')],
+        command : [generate_af_list, cpp, files('include/sys/socket.h')],
         capture : true)
 
 generate_arphrd_list = find_program('generate-arphrd-list.sh')
diff --git a/src/basic/missing_syscall.h b/src/basic/missing_syscall.h
index ec62602989..76074d1c04 100644
--- a/src/basic/missing_syscall.h
+++ b/src/basic/missing_syscall.h
@@ -4,6 +4,7 @@
 /* Missing glibc definitions to access certain kernel APIs */
 
 #include <linux/mempolicy.h>
+#include <sched.h>
 #include <signal.h>
 #include <sys/syscall.h>
 #include <sys/xattr.h>
@@ -15,7 +16,6 @@
 
 #include "forward.h"
 #include "missing_keyctl.h"
-#include "missing_sched.h"
 #include "missing_syscall_def.h"
 
 /* ======================================================================= */
diff --git a/src/basic/namespace-util.c b/src/basic/namespace-util.c
index bed67619e2..35a8693cb1 100644
--- a/src/basic/namespace-util.c
+++ b/src/basic/namespace-util.c
@@ -11,7 +11,6 @@
 #include "log.h"
 #include "missing_magic.h"
 #include "missing_namespace.h"
-#include "missing_sched.h"
 #include "mountpoint-util.h"
 #include "namespace-util.h"
 #include "parse-util.h"
diff --git a/src/basic/pidfd-util.h b/src/basic/pidfd-util.h
index e998b8a3bc..0cc247ced1 100644
--- a/src/basic/pidfd-util.h
+++ b/src/basic/pidfd-util.h
@@ -1,8 +1,9 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
+#include <sys/pidfd.h>          /* IWYU pragma: export */
+
 #include "forward.h"
-#include "missing_pidfd.h"      /* IWYU pragma: export */
 #include "missing_syscall.h"    /* IWYU pragma: export */
 
 int pidfd_get_namespace(int fd, unsigned long ns_type_cmd);
diff --git a/src/basic/pidref.c b/src/basic/pidref.c
index 3aee706a9c..e4c51dd952 100644
--- a/src/basic/pidref.c
+++ b/src/basic/pidref.c
@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
+#include <sys/wait.h>
 #include <unistd.h>
 
 #include "alloc-util.h"
@@ -8,7 +9,6 @@
 #include "format-util.h"
 #include "hash-funcs.h"
 #include "log.h"
-#include "missing_wait.h"
 #include "parse-util.h"
 #include "pidfd-util.h"
 #include "pidref.h"
diff --git a/src/basic/process-util.c b/src/basic/process-util.c
index e05329b406..1d341aa0a7 100644
--- a/src/basic/process-util.c
+++ b/src/basic/process-util.c
@@ -34,7 +34,6 @@
 #include "locale-util.h"
 #include "log.h"
 #include "memory-util.h"
-#include "missing_sched.h"
 #include "missing_syscall.h"
 #include "mountpoint-util.h"
 #include "namespace-util.h"
diff --git a/src/basic/random-util.c b/src/basic/random-util.c
index 1726873237..ece0e41943 100644
--- a/src/basic/random-util.c
+++ b/src/basic/random-util.c
@@ -6,6 +6,7 @@
 #include <string.h>
 #include <sys/auxv.h>
 #include <sys/ioctl.h>
+#include <sys/random.h>
 #include <threads.h>
 #include <unistd.h>
 
@@ -15,7 +16,6 @@
 #include "io-util.h"
 #include "iovec-util.h"
 #include "log.h"
-#include "missing_random.h"
 #include "parse-util.h"
 #include "pidfd-util.h"
 #include "process-util.h"
diff --git a/src/basic/raw-clone.h b/src/basic/raw-clone.h
index 91b0069fb5..36202cc0ba 100644
--- a/src/basic/raw-clone.h
+++ b/src/basic/raw-clone.h
@@ -11,7 +11,6 @@
 
 #include "log.h"
 #include "macro.h"
-#include "missing_sched.h"
 #include "process-util.h"
 
 /**
diff --git a/src/basic/socket-util.h b/src/basic/socket-util.h
index 6493ccb468..24883d2db2 100644
--- a/src/basic/socket-util.h
+++ b/src/basic/socket-util.h
@@ -13,7 +13,6 @@
 #include "forward.h"
 #include "memory-util.h"
 #include "missing_network.h"
-#include "missing_socket.h"
 
 union sockaddr_union {
         /* The minimal, abstract version */
diff --git a/src/core/dbus-service.c b/src/core/dbus-service.c
index 0d5c5041f8..da522227c0 100644
--- a/src/core/dbus-service.c
+++ b/src/core/dbus-service.c
@@ -22,7 +22,6 @@
 #include "glyph-util.h"
 #include "locale-util.h"
 #include "manager.h"
-#include "missing_fcntl.h"
 #include "mount-util.h"
 #include "open-file.h"
 #include "path-util.h"
diff --git a/src/core/exec-invoke.c b/src/core/exec-invoke.c
index ec6729ae37..a73f87279f 100644
--- a/src/core/exec-invoke.c
+++ b/src/core/exec-invoke.c
@@ -52,7 +52,6 @@
 #include "journal-send.h"
 #include "manager.h"
 #include "memfd-util.h"
-#include "missing_sched.h"
 #include "missing_syscall.h"
 #include "mkdir-label.h"
 #include "mount-util.h"
diff --git a/src/home/homed-home.c b/src/home/homed-home.c
index 90e3944f6b..d8683b8211 100644
--- a/src/home/homed-home.c
+++ b/src/home/homed-home.c
@@ -1,6 +1,5 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
-#include <sys/mman.h>
 #include <sys/vfs.h>
 #include <unistd.h>
 
@@ -29,7 +28,6 @@
 #include "json-util.h"
 #include "log.h"
 #include "memfd-util.h"
-#include "missing_mman.h"
 #include "mkdir.h"
 #include "ordered-set.h"
 #include "parse-util.h"
diff --git a/src/journal/journalctl-filter.c b/src/journal/journalctl-filter.c
index d29237e43b..54a54d105c 100644
--- a/src/journal/journalctl-filter.c
+++ b/src/journal/journalctl-filter.c
@@ -1,5 +1,7 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
+#include <sched.h>
+
 #include "sd-device.h"
 #include "sd-journal.h"
 
@@ -14,7 +16,6 @@
 #include "journalctl-util.h"
 #include "log.h"
 #include "logs-show.h"
-#include "missing_sched.h"
 #include "path-util.h"
 #include "set.h"
 #include "stat-util.h"
diff --git a/src/journal/journald-native.c b/src/journal/journald-native.c
index a428108d14..4288bd4f3f 100644
--- a/src/journal/journald-native.c
+++ b/src/journal/journald-native.c
@@ -1,6 +1,5 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
-#include <sys/mman.h>
 #include <sys/statvfs.h>
 #include <unistd.h>
 
diff --git a/src/libsystemd/sd-bus/bus-message.c b/src/libsystemd/sd-bus/bus-message.c
index 22ae012041..64f4f0e223 100644
--- a/src/libsystemd/sd-bus/bus-message.c
+++ b/src/libsystemd/sd-bus/bus-message.c
@@ -1,7 +1,5 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
-#include <sys/mman.h>
-
 #include "sd-bus.h"
 
 #include "alloc-util.h"
diff --git a/src/libsystemd/sd-event/sd-event.c b/src/libsystemd/sd-event/sd-event.c
index 3345a6a80a..671fedf6fd 100644
--- a/src/libsystemd/sd-event/sd-event.c
+++ b/src/libsystemd/sd-event/sd-event.c
@@ -25,7 +25,6 @@
 #include "logarithm.h"
 #include "memory-util.h"
 #include "missing_magic.h"
-#include "missing_wait.h"
 #include "origin-id.h"
 #include "path-util.h"
 #include "pidfd-util.h"
diff --git a/src/libsystemd/sd-journal/journal-file.h b/src/libsystemd/sd-journal/journal-file.h
index 12a6646853..9598879066 100644
--- a/src/libsystemd/sd-journal/journal-file.h
+++ b/src/libsystemd/sd-journal/journal-file.h
@@ -1,11 +1,12 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
+#include <fcntl.h>
+
 #include "compress.h"
 #include "forward.h"
 #include "gcrypt-util.h"
 #include "journal-def.h"
-#include "missing_fcntl.h"
 #include "mmap-cache.h"
 #include "sparse-endian.h"
 
diff --git a/src/libsystemd/sd-journal/journal-send.c b/src/libsystemd/sd-journal/journal-send.c
index 8a1e0b1fdf..e838e7e0d7 100644
--- a/src/libsystemd/sd-journal/journal-send.c
+++ b/src/libsystemd/sd-journal/journal-send.c
@@ -18,7 +18,6 @@
 #include "journal-send.h"
 #include "log.h"
 #include "memfd-util.h"
-#include "missing_mman.h"
 #include "process-util.h"
 #include "socket-util.h"
 #include "stdio-util.h"
diff --git a/src/nsresourced/nsresourcework.c b/src/nsresourced/nsresourcework.c
index 3ec575ac48..7157106c08 100644
--- a/src/nsresourced/nsresourcework.c
+++ b/src/nsresourced/nsresourcework.c
@@ -30,7 +30,6 @@
 #include "json-util.h"
 #include "main-func.h"
 #include "missing_magic.h"
-#include "missing_sched.h"
 #include "missing_syscall.h"
 #include "mountpoint-util.h"
 #include "namespace-util.h"
diff --git a/src/nsresourced/test-userns-restrict.c b/src/nsresourced/test-userns-restrict.c
index e4741784f2..68ac3e4722 100644
--- a/src/nsresourced/test-userns-restrict.c
+++ b/src/nsresourced/test-userns-restrict.c
@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
+#include <sched.h>
 #include <sys/eventfd.h>
 #include <sys/mount.h>
 #include <sys/stat.h>
@@ -9,7 +10,6 @@
 #include "fd-util.h"
 #include "log.h"
 #include "main-func.h"
-#include "missing_sched.h"
 #include "namespace-util.h"
 #include "process-util.h"
 #include "rm-rf.h"
diff --git a/src/random-seed/random-seed-tool.c b/src/random-seed/random-seed-tool.c
index a99df0e08e..b539c1f654 100644
--- a/src/random-seed/random-seed-tool.c
+++ b/src/random-seed/random-seed-tool.c
@@ -3,6 +3,7 @@
 #include <fcntl.h>
 #include <getopt.h>
 #include <stdlib.h>
+#include <sys/random.h>
 #include <sys/stat.h>
 #include <sys/xattr.h>
 #include <unistd.h>
@@ -17,7 +18,6 @@
 #include "io-util.h"
 #include "log.h"
 #include "main-func.h"
-#include "missing_random.h"
 #include "mkdir.h"
 #include "parse-util.h"
 #include "pretty-print.h"
diff --git a/src/resolve/resolved-manager.c b/src/resolve/resolved-manager.c
index 95f0cac49c..d4eb6b8c0a 100644
--- a/src/resolve/resolved-manager.c
+++ b/src/resolve/resolved-manager.c
@@ -25,7 +25,6 @@
 #include "json-util.h"
 #include "memstream-util.h"
 #include "missing_network.h"
-#include "missing_socket.h"
 #include "ordered-set.h"
 #include "parse-util.h"
 #include "random-util.h"
diff --git a/src/shared/data-fd-util.c b/src/shared/data-fd-util.c
index a9b799bd61..c91d056149 100644
--- a/src/shared/data-fd-util.c
+++ b/src/shared/data-fd-util.c
@@ -8,7 +8,6 @@
 #include "fd-util.h"
 #include "fs-util.h"
 #include "memfd-util.h"
-#include "missing_mman.h"
 #include "tmpfile-util.h"
 
 /* When the data is smaller or equal to 64K, try to place the copy in a memfd */
diff --git a/src/shared/nsflags.h b/src/shared/nsflags.h
index 1bb46d3d3c..35bcb6a8c9 100644
--- a/src/shared/nsflags.h
+++ b/src/shared/nsflags.h
@@ -1,8 +1,9 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
+#include <sched.h>
+
 #include "forward.h"
-#include "missing_sched.h"
 
 /* The combination of all namespace flags defined by the kernel. The right type for this isn't clear. setns() and
  * unshare() expect these flags to be passed as (signed) "int", while clone() wants them as "unsigned long". The latter
diff --git a/src/shared/nsresource.c b/src/shared/nsresource.c
index e74e5fcc70..d199d437d5 100644
--- a/src/shared/nsresource.c
+++ b/src/shared/nsresource.c
@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 
+#include <sched.h>
 #include <sys/prctl.h>
 
 #include "sd-varlink.h"
@@ -9,7 +10,6 @@
 #include "format-util.h"
 #include "json-util.h"
 #include "log.h"
-#include "missing_sched.h"
 #include "namespace-util.h"
 #include "nsresource.h"
 #include "process-util.h"
diff --git a/src/shared/serialize.c b/src/shared/serialize.c
index a0b41b281e..f7d60ac0b7 100644
--- a/src/shared/serialize.c
+++ b/src/shared/serialize.c
@@ -17,7 +17,6 @@
 #include "image-policy.h"
 #include "log.h"
 #include "memfd-util.h"
-#include "missing_mman.h"
 #include "parse-util.h"
 #include "pidref.h"
 #include "ratelimit.h"
diff --git a/src/ssh-generator/ssh-generator.c b/src/ssh-generator/ssh-generator.c
index eaa4dec764..3f1fd8cc30 100644
--- a/src/ssh-generator/ssh-generator.c
+++ b/src/ssh-generator/ssh-generator.c
@@ -10,7 +10,6 @@
 #include "generator.h"
 #include "install.h"
 #include "log.h"
-#include "missing_socket.h"
 #include "parse-util.h"
 #include "path-lookup.h"
 #include "path-util.h"
diff --git a/src/ssh-generator/ssh-proxy.c b/src/ssh-generator/ssh-proxy.c
index 38f6477914..30360b18b4 100644
--- a/src/ssh-generator/ssh-proxy.c
+++ b/src/ssh-generator/ssh-proxy.c
@@ -10,7 +10,6 @@
 #include "iovec-util.h"
 #include "log.h"
 #include "main-func.h"
-#include "missing_socket.h"
 #include "socket-util.h"
 #include "string-util.h"
 #include "strv.h"
diff --git a/src/test/test-argv-util.c b/src/test/test-argv-util.c
index 4a3ac700ac..f7a99ff26d 100644
--- a/src/test/test-argv-util.c
+++ b/src/test/test-argv-util.c
@@ -8,7 +8,6 @@
 #endif
 
 #include "argv-util.h"
-#include "missing_sched.h"
 #include "process-util.h"
 #include "tests.h"
 #include "virt.h"
diff --git a/src/test/test-memfd-util.c b/src/test/test-memfd-util.c
index 2cfae57f66..971a9a8dc0 100644
--- a/src/test/test-memfd-util.c
+++ b/src/test/test-memfd-util.c
@@ -5,7 +5,6 @@
 #include "errno-util.h"
 #include "fd-util.h"
 #include "memfd-util.h"
-#include "missing_mman.h"
 #include "tests.h"
 
 TEST(memfd_get_sealed) {
diff --git a/src/test/test-process-util.c b/src/test/test-process-util.c
index c0095a749c..4b713a3dde 100644
--- a/src/test/test-process-util.c
+++ b/src/test/test-process-util.c
@@ -26,7 +26,6 @@
 #include "fd-util.h"
 #include "ioprio-util.h"
 #include "log.h"
-#include "missing_sched.h"
 #include "namespace-util.h"
 #include "parse-util.h"
 #include "pidfd-util.h"
diff --git a/src/test/test-raw-clone.c b/src/test/test-raw-clone.c
index 097bbfe29a..3a0da73b82 100644
--- a/src/test/test-raw-clone.c
+++ b/src/test/test-raw-clone.c
@@ -5,7 +5,6 @@
 
 #include "errno-util.h"
 #include "format-util.h"
-#include "missing_sched.h"
 #include "raw-clone.h"
 #include "tests.h"
 
diff --git a/src/test/test-seccomp.c b/src/test/test-seccomp.c
index 9acb558d40..7199b2fb33 100644
--- a/src/test/test-seccomp.c
+++ b/src/test/test-seccomp.c
@@ -21,7 +21,6 @@
 #include "fileio.h"
 #include "fs-util.h"
 #include "memory-util.h"
-#include "missing_sched.h"
 #include "missing_syscall.h"
 #include "nsflags.h"
 #include "nulstr-util.h"