diff --git a/Include/cpython/pystate.h b/Include/cpython/pystate.h
new file mode 100644
index 00000000000..78e9a5ed101
--- /dev/null
+++ b/Include/cpython/pystate.h
@@ -0,0 +1,272 @@
+#ifndef Py_CPYTHON_PYSTATE_H
+#  error "this header file must not be included directly"
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef PyObject* (*_PyFrameEvalFunction)(struct _frame *, int);
+
+/* Placeholders while working on the new configuration API
+ *
+ * See PEP 432 for final anticipated contents
+ */
+typedef struct {
+    int install_signal_handlers;   /* Install signal handlers? -1 means unset */
+    PyObject *argv;                /* sys.argv list, can be NULL */
+    PyObject *executable;          /* sys.executable str */
+    PyObject *prefix;              /* sys.prefix str */
+    PyObject *base_prefix;         /* sys.base_prefix str, can be NULL */
+    PyObject *exec_prefix;         /* sys.exec_prefix str */
+    PyObject *base_exec_prefix;    /* sys.base_exec_prefix str, can be NULL */
+    PyObject *warnoptions;         /* sys.warnoptions list, can be NULL */
+    PyObject *xoptions;            /* sys._xoptions dict, can be NULL */
+    PyObject *module_search_path;  /* sys.path list */
+    PyObject *pycache_prefix;      /* sys.pycache_prefix str, can be NULL */
+} _PyMainInterpreterConfig;
+
+#define _PyMainInterpreterConfig_INIT \
+    (_PyMainInterpreterConfig){.install_signal_handlers = -1}
+/* Note: _PyMainInterpreterConfig_INIT sets other fields to 0/NULL */
+
+typedef struct _is {
+
+    struct _is *next;
+    struct _ts *tstate_head;
+
+    int64_t id;
+    int64_t id_refcount;
+    PyThread_type_lock id_mutex;
+
+    PyObject *modules;
+    PyObject *modules_by_index;
+    PyObject *sysdict;
+    PyObject *builtins;
+    PyObject *importlib;
+
+    /* Used in Python/sysmodule.c. */
+    int check_interval;
+
+    /* Used in Modules/_threadmodule.c. */
+    long num_threads;
+    /* Support for runtime thread stack size tuning.
+       A value of 0 means using the platform's default stack size
+       or the size specified by the THREAD_STACK_SIZE macro. */
+    /* Used in Python/thread.c. */
+    size_t pythread_stacksize;
+
+    PyObject *codec_search_path;
+    PyObject *codec_search_cache;
+    PyObject *codec_error_registry;
+    int codecs_initialized;
+    int fscodec_initialized;
+
+    _PyCoreConfig core_config;
+    _PyMainInterpreterConfig config;
+#ifdef HAVE_DLOPEN
+    int dlopenflags;
+#endif
+
+    PyObject *builtins_copy;
+    PyObject *import_func;
+    /* Initialized to PyEval_EvalFrameDefault(). */
+    _PyFrameEvalFunction eval_frame;
+
+    Py_ssize_t co_extra_user_count;
+    freefunc co_extra_freefuncs[MAX_CO_EXTRA_USERS];
+
+#ifdef HAVE_FORK
+    PyObject *before_forkers;
+    PyObject *after_forkers_parent;
+    PyObject *after_forkers_child;
+#endif
+    /* AtExit module */
+    void (*pyexitfunc)(PyObject *);
+    PyObject *pyexitmodule;
+
+    uint64_t tstate_next_unique_id;
+} PyInterpreterState;
+
+/* State unique per thread */
+
+/* Py_tracefunc return -1 when raising an exception, or 0 for success. */
+typedef int (*Py_tracefunc)(PyObject *, struct _frame *, int, PyObject *);
+
+/* The following values are used for 'what' for tracefunc functions
+ *
+ * To add a new kind of trace event, also update "trace_init" in
+ * Python/sysmodule.c to define the Python level event name
+ */
+#define PyTrace_CALL 0
+#define PyTrace_EXCEPTION 1
+#define PyTrace_LINE 2
+#define PyTrace_RETURN 3
+#define PyTrace_C_CALL 4
+#define PyTrace_C_EXCEPTION 5
+#define PyTrace_C_RETURN 6
+#define PyTrace_OPCODE 7
+
+
+typedef struct _err_stackitem {
+    /* This struct represents an entry on the exception stack, which is a
+     * per-coroutine state. (Coroutine in the computer science sense,
+     * including the thread and generators).
+     * This ensures that the exception state is not impacted by "yields"
+     * from an except handler.
+     */
+    PyObject *exc_type, *exc_value, *exc_traceback;
+
+    struct _err_stackitem *previous_item;
+
+} _PyErr_StackItem;
+
+
+typedef struct _ts {
+    /* See Python/ceval.c for comments explaining most fields */
+
+    struct _ts *prev;
+    struct _ts *next;
+    PyInterpreterState *interp;
+
+    struct _frame *frame;
+    int recursion_depth;
+    char overflowed; /* The stack has overflowed. Allow 50 more calls
+                        to handle the runtime error. */
+    char recursion_critical; /* The current calls must not cause
+                                a stack overflow. */
+    int stackcheck_counter;
+
+    /* 'tracing' keeps track of the execution depth when tracing/profiling.
+       This is to prevent the actual trace/profile code from being recorded in
+       the trace/profile. */
+    int tracing;
+    int use_tracing;
+
+    Py_tracefunc c_profilefunc;
+    Py_tracefunc c_tracefunc;
+    PyObject *c_profileobj;
+    PyObject *c_traceobj;
+
+    /* The exception currently being raised */
+    PyObject *curexc_type;
+    PyObject *curexc_value;
+    PyObject *curexc_traceback;
+
+    /* The exception currently being handled, if no coroutines/generators
+     * are present. Always last element on the stack referred to be exc_info.
+     */
+    _PyErr_StackItem exc_state;
+
+    /* Pointer to the top of the stack of the exceptions currently
+     * being handled */
+    _PyErr_StackItem *exc_info;
+
+    PyObject *dict;  /* Stores per-thread state */
+
+    int gilstate_counter;
+
+    PyObject *async_exc; /* Asynchronous exception to raise */
+    unsigned long thread_id; /* Thread id where this tstate was created */
+
+    int trash_delete_nesting;
+    PyObject *trash_delete_later;
+
+    /* Called when a thread state is deleted normally, but not when it
+     * is destroyed after fork().
+     * Pain:  to prevent rare but fatal shutdown errors (issue 18808),
+     * Thread.join() must wait for the join'ed thread's tstate to be unlinked
+     * from the tstate chain.  That happens at the end of a thread's life,
+     * in pystate.c.
+     * The obvious way doesn't quite work:  create a lock which the tstate
+     * unlinking code releases, and have Thread.join() wait to acquire that
+     * lock.  The problem is that we _are_ at the end of the thread's life:
+     * if the thread holds the last reference to the lock, decref'ing the
+     * lock will delete the lock, and that may trigger arbitrary Python code
+     * if there's a weakref, with a callback, to the lock.  But by this time
+     * _PyRuntime.gilstate.tstate_current is already NULL, so only the simplest
+     * of C code can be allowed to run (in particular it must not be possible to
+     * release the GIL).
+     * So instead of holding the lock directly, the tstate holds a weakref to
+     * the lock:  that's the value of on_delete_data below.  Decref'ing a
+     * weakref is harmless.
+     * on_delete points to _threadmodule.c's static release_sentinel() function.
+     * After the tstate is unlinked, release_sentinel is called with the
+     * weakref-to-lock (on_delete_data) argument, and release_sentinel releases
+     * the indirectly held lock.
+     */
+    void (*on_delete)(void *);
+    void *on_delete_data;
+
+    int coroutine_origin_tracking_depth;
+
+    PyObject *coroutine_wrapper;
+    int in_coroutine_wrapper;
+
+    PyObject *async_gen_firstiter;
+    PyObject *async_gen_finalizer;
+
+    PyObject *context;
+    uint64_t context_ver;
+
+    /* Unique thread state id. */
+    uint64_t id;
+
+    /* XXX signal handlers should also be here */
+
+} PyThreadState;
+
+/* Get the current interpreter state.
+
+   Issue a fatal error if there no current Python thread state or no current
+   interpreter. It cannot return NULL.
+
+   The caller must hold the GIL.*/
+PyAPI_FUNC(PyInterpreterState *) _PyInterpreterState_Get(void);
+
+PyAPI_FUNC(int) _PyState_AddModule(PyObject*, struct PyModuleDef*);
+PyAPI_FUNC(void) _PyState_ClearModules(void);
+PyAPI_FUNC(PyThreadState *) _PyThreadState_Prealloc(PyInterpreterState *);
+PyAPI_FUNC(void) _PyThreadState_Init(PyThreadState *);
+PyAPI_FUNC(void) _PyThreadState_DeleteExcept(PyThreadState *tstate);
+PyAPI_FUNC(void) _PyGILState_Reinit(void);
+
+/* Similar to PyThreadState_Get(), but don't issue a fatal error
+ * if it is NULL. */
+PyAPI_FUNC(PyThreadState *) _PyThreadState_UncheckedGet(void);
+
+/* PyGILState */
+
+/* Helper/diagnostic function - return 1 if the current thread
+   currently holds the GIL, 0 otherwise.
+
+   The function returns 1 if _PyGILState_check_enabled is non-zero. */
+PyAPI_FUNC(int) PyGILState_Check(void);
+
+/* Get the single PyInterpreterState used by this process' GILState
+   implementation.
+
+   This function doesn't check for error. Return NULL before _PyGILState_Init()
+   is called and after _PyGILState_Fini() is called.
+
+   See also _PyInterpreterState_Get() and _PyInterpreterState_GET_UNSAFE(). */
+PyAPI_FUNC(PyInterpreterState *) _PyGILState_GetInterpreterStateUnsafe(void);
+
+/* The implementation of sys._current_frames()  Returns a dict mapping
+   thread id to that thread's current frame.
+*/
+PyAPI_FUNC(PyObject *) _PyThread_CurrentFrames(void);
+
+/* Routines for advanced debuggers, requested by David Beazley.
+   Don't use unless you know what you are doing! */
+PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_Main(void);
+PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_Head(void);
+PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_Next(PyInterpreterState *);
+PyAPI_FUNC(PyThreadState *) PyInterpreterState_ThreadHead(PyInterpreterState *);
+PyAPI_FUNC(PyThreadState *) PyThreadState_Next(PyThreadState *);
+
+typedef struct _frame *(*PyThreadFrameGetter)(PyThreadState *self_);
+
+#ifdef __cplusplus
+}
+#endif
diff --git a/Include/pystate.h b/Include/pystate.h
index 58499ea35b4..cc479ff867a 100644
--- a/Include/pystate.h
+++ b/Include/pystate.h
@@ -20,273 +20,31 @@ struct _ts; /* Forward */
 struct _is; /* Forward */
 struct _frame; /* Forward declaration for PyFrameObject. */
 
-#ifdef Py_LIMITED_API
 typedef struct _is PyInterpreterState;
-#else
-typedef PyObject* (*_PyFrameEvalFunction)(struct _frame *, int);
-
-/* Placeholders while working on the new configuration API
- *
- * See PEP 432 for final anticipated contents
- */
-typedef struct {
-    int install_signal_handlers;   /* Install signal handlers? -1 means unset */
-    PyObject *argv;                /* sys.argv list, can be NULL */
-    PyObject *executable;          /* sys.executable str */
-    PyObject *prefix;              /* sys.prefix str */
-    PyObject *base_prefix;         /* sys.base_prefix str, can be NULL */
-    PyObject *exec_prefix;         /* sys.exec_prefix str */
-    PyObject *base_exec_prefix;    /* sys.base_exec_prefix str, can be NULL */
-    PyObject *warnoptions;         /* sys.warnoptions list, can be NULL */
-    PyObject *xoptions;            /* sys._xoptions dict, can be NULL */
-    PyObject *module_search_path;  /* sys.path list */
-    PyObject *pycache_prefix;      /* sys.pycache_prefix str, can be NULL */
-} _PyMainInterpreterConfig;
-
-#define _PyMainInterpreterConfig_INIT \
-    (_PyMainInterpreterConfig){.install_signal_handlers = -1}
-/* Note: _PyMainInterpreterConfig_INIT sets other fields to 0/NULL */
-
-typedef struct _is {
-
-    struct _is *next;
-    struct _ts *tstate_head;
-
-    int64_t id;
-    int64_t id_refcount;
-    PyThread_type_lock id_mutex;
-
-    PyObject *modules;
-    PyObject *modules_by_index;
-    PyObject *sysdict;
-    PyObject *builtins;
-    PyObject *importlib;
-
-    /* Used in Python/sysmodule.c. */
-    int check_interval;
-
-    /* Used in Modules/_threadmodule.c. */
-    long num_threads;
-    /* Support for runtime thread stack size tuning.
-       A value of 0 means using the platform's default stack size
-       or the size specified by the THREAD_STACK_SIZE macro. */
-    /* Used in Python/thread.c. */
-    size_t pythread_stacksize;
-
-    PyObject *codec_search_path;
-    PyObject *codec_search_cache;
-    PyObject *codec_error_registry;
-    int codecs_initialized;
-    int fscodec_initialized;
-
-    _PyCoreConfig core_config;
-    _PyMainInterpreterConfig config;
-#ifdef HAVE_DLOPEN
-    int dlopenflags;
-#endif
-
-    PyObject *builtins_copy;
-    PyObject *import_func;
-    /* Initialized to PyEval_EvalFrameDefault(). */
-    _PyFrameEvalFunction eval_frame;
-
-    Py_ssize_t co_extra_user_count;
-    freefunc co_extra_freefuncs[MAX_CO_EXTRA_USERS];
-
-#ifdef HAVE_FORK
-    PyObject *before_forkers;
-    PyObject *after_forkers_parent;
-    PyObject *after_forkers_child;
-#endif
-    /* AtExit module */
-    void (*pyexitfunc)(PyObject *);
-    PyObject *pyexitmodule;
-
-    uint64_t tstate_next_unique_id;
-} PyInterpreterState;
-#endif   /* !Py_LIMITED_API */
-
 
 /* State unique per thread */
 
-#ifndef Py_LIMITED_API
-/* Py_tracefunc return -1 when raising an exception, or 0 for success. */
-typedef int (*Py_tracefunc)(PyObject *, struct _frame *, int, PyObject *);
-
-/* The following values are used for 'what' for tracefunc functions
- *
- * To add a new kind of trace event, also update "trace_init" in
- * Python/sysmodule.c to define the Python level event name
- */
-#define PyTrace_CALL 0
-#define PyTrace_EXCEPTION 1
-#define PyTrace_LINE 2
-#define PyTrace_RETURN 3
-#define PyTrace_C_CALL 4
-#define PyTrace_C_EXCEPTION 5
-#define PyTrace_C_RETURN 6
-#define PyTrace_OPCODE 7
-#endif   /* Py_LIMITED_API */
-
-#ifdef Py_LIMITED_API
 typedef struct _ts PyThreadState;
-#else
-
-typedef struct _err_stackitem {
-    /* This struct represents an entry on the exception stack, which is a
-     * per-coroutine state. (Coroutine in the computer science sense,
-     * including the thread and generators).
-     * This ensures that the exception state is not impacted by "yields"
-     * from an except handler.
-     */
-    PyObject *exc_type, *exc_value, *exc_traceback;
-
-    struct _err_stackitem *previous_item;
-
-} _PyErr_StackItem;
-
-
-typedef struct _ts {
-    /* See Python/ceval.c for comments explaining most fields */
-
-    struct _ts *prev;
-    struct _ts *next;
-    PyInterpreterState *interp;
-
-    struct _frame *frame;
-    int recursion_depth;
-    char overflowed; /* The stack has overflowed. Allow 50 more calls
-                        to handle the runtime error. */
-    char recursion_critical; /* The current calls must not cause
-                                a stack overflow. */
-    int stackcheck_counter;
-
-    /* 'tracing' keeps track of the execution depth when tracing/profiling.
-       This is to prevent the actual trace/profile code from being recorded in
-       the trace/profile. */
-    int tracing;
-    int use_tracing;
-
-    Py_tracefunc c_profilefunc;
-    Py_tracefunc c_tracefunc;
-    PyObject *c_profileobj;
-    PyObject *c_traceobj;
-
-    /* The exception currently being raised */
-    PyObject *curexc_type;
-    PyObject *curexc_value;
-    PyObject *curexc_traceback;
-
-    /* The exception currently being handled, if no coroutines/generators
-     * are present. Always last element on the stack referred to be exc_info.
-     */
-    _PyErr_StackItem exc_state;
-
-    /* Pointer to the top of the stack of the exceptions currently
-     * being handled */
-    _PyErr_StackItem *exc_info;
-
-    PyObject *dict;  /* Stores per-thread state */
-
-    int gilstate_counter;
-
-    PyObject *async_exc; /* Asynchronous exception to raise */
-    unsigned long thread_id; /* Thread id where this tstate was created */
-
-    int trash_delete_nesting;
-    PyObject *trash_delete_later;
-
-    /* Called when a thread state is deleted normally, but not when it
-     * is destroyed after fork().
-     * Pain:  to prevent rare but fatal shutdown errors (issue 18808),
-     * Thread.join() must wait for the join'ed thread's tstate to be unlinked
-     * from the tstate chain.  That happens at the end of a thread's life,
-     * in pystate.c.
-     * The obvious way doesn't quite work:  create a lock which the tstate
-     * unlinking code releases, and have Thread.join() wait to acquire that
-     * lock.  The problem is that we _are_ at the end of the thread's life:
-     * if the thread holds the last reference to the lock, decref'ing the
-     * lock will delete the lock, and that may trigger arbitrary Python code
-     * if there's a weakref, with a callback, to the lock.  But by this time
-     * _PyRuntime.gilstate.tstate_current is already NULL, so only the simplest
-     * of C code can be allowed to run (in particular it must not be possible to
-     * release the GIL).
-     * So instead of holding the lock directly, the tstate holds a weakref to
-     * the lock:  that's the value of on_delete_data below.  Decref'ing a
-     * weakref is harmless.
-     * on_delete points to _threadmodule.c's static release_sentinel() function.
-     * After the tstate is unlinked, release_sentinel is called with the
-     * weakref-to-lock (on_delete_data) argument, and release_sentinel releases
-     * the indirectly held lock.
-     */
-    void (*on_delete)(void *);
-    void *on_delete_data;
-
-    int coroutine_origin_tracking_depth;
-
-    PyObject *coroutine_wrapper;
-    int in_coroutine_wrapper;
-
-    PyObject *async_gen_firstiter;
-    PyObject *async_gen_finalizer;
-
-    PyObject *context;
-    uint64_t context_ver;
-
-    /* Unique thread state id. */
-    uint64_t id;
-
-    /* XXX signal handlers should also be here */
-
-} PyThreadState;
-#endif   /* !Py_LIMITED_API */
-
 
 PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_New(void);
 PyAPI_FUNC(void) PyInterpreterState_Clear(PyInterpreterState *);
 PyAPI_FUNC(void) PyInterpreterState_Delete(PyInterpreterState *);
 
-#if !defined(Py_LIMITED_API)
-/* Get the current interpreter state.
-
-   Issue a fatal error if there no current Python thread state or no current
-   interpreter. It cannot return NULL.
-
-   The caller must hold the GIL.*/
-PyAPI_FUNC(PyInterpreterState *) _PyInterpreterState_Get(void);
-#endif
-
 #if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03070000
 /* New in 3.7 */
 PyAPI_FUNC(int64_t) PyInterpreterState_GetID(PyInterpreterState *);
 #endif
-#ifndef Py_LIMITED_API
-PyAPI_FUNC(int) _PyState_AddModule(PyObject*, struct PyModuleDef*);
-#endif /* !Py_LIMITED_API */
 #if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03030000
 /* New in 3.3 */
 PyAPI_FUNC(int) PyState_AddModule(PyObject*, struct PyModuleDef*);
 PyAPI_FUNC(int) PyState_RemoveModule(struct PyModuleDef*);
 #endif
 PyAPI_FUNC(PyObject*) PyState_FindModule(struct PyModuleDef*);
-#ifndef Py_LIMITED_API
-PyAPI_FUNC(void) _PyState_ClearModules(void);
-#endif
 
 PyAPI_FUNC(PyThreadState *) PyThreadState_New(PyInterpreterState *);
-#ifndef Py_LIMITED_API
-PyAPI_FUNC(PyThreadState *) _PyThreadState_Prealloc(PyInterpreterState *);
-PyAPI_FUNC(void) _PyThreadState_Init(PyThreadState *);
-#endif /* !Py_LIMITED_API */
 PyAPI_FUNC(void) PyThreadState_Clear(PyThreadState *);
 PyAPI_FUNC(void) PyThreadState_Delete(PyThreadState *);
-#ifndef Py_LIMITED_API
-PyAPI_FUNC(void) _PyThreadState_DeleteExcept(PyThreadState *tstate);
-#endif /* !Py_LIMITED_API */
 PyAPI_FUNC(void) PyThreadState_DeleteCurrent(void);
-#ifndef Py_LIMITED_API
-PyAPI_FUNC(void) _PyGILState_Reinit(void);
-#endif /* !Py_LIMITED_API */
 
 /* Get the current thread state.
 
@@ -309,12 +67,6 @@ PyAPI_FUNC(PyThreadState *) PyThreadState_Get(void);
    See also PyThreadState_Get() and _PyThreadState_GET(). */
 #define PyThreadState_GET() PyThreadState_Get()
 
-#ifndef Py_LIMITED_API
-/* Similar to PyThreadState_Get(), but don't issue a fatal error
- * if it is NULL. */
-PyAPI_FUNC(PyThreadState *) _PyThreadState_UncheckedGet(void);
-#endif /* !Py_LIMITED_API */
-
 PyAPI_FUNC(PyThreadState *) PyThreadState_Swap(PyThreadState *);
 PyAPI_FUNC(PyObject *) PyThreadState_GetDict(void);
 PyAPI_FUNC(int) PyThreadState_SetAsyncExc(unsigned long, PyObject *);
@@ -365,41 +117,11 @@ PyAPI_FUNC(void) PyGILState_Release(PyGILState_STATE);
 */
 PyAPI_FUNC(PyThreadState *) PyGILState_GetThisThreadState(void);
 
+
 #ifndef Py_LIMITED_API
-/* Helper/diagnostic function - return 1 if the current thread
-   currently holds the GIL, 0 otherwise.
-
-   The function returns 1 if _PyGILState_check_enabled is non-zero. */
-PyAPI_FUNC(int) PyGILState_Check(void);
-
-/* Get the single PyInterpreterState used by this process' GILState
-   implementation.
-
-   This function doesn't check for error. Return NULL before _PyGILState_Init()
-   is called and after _PyGILState_Fini() is called.
-
-   See also _PyInterpreterState_Get() and _PyInterpreterState_GET_UNSAFE(). */
-PyAPI_FUNC(PyInterpreterState *) _PyGILState_GetInterpreterStateUnsafe(void);
-#endif   /* !Py_LIMITED_API */
-
-
-/* The implementation of sys._current_frames()  Returns a dict mapping
-   thread id to that thread's current frame.
-*/
-#ifndef Py_LIMITED_API
-PyAPI_FUNC(PyObject *) _PyThread_CurrentFrames(void);
-#endif
-
-/* Routines for advanced debuggers, requested by David Beazley.
-   Don't use unless you know what you are doing! */
-#ifndef Py_LIMITED_API
-PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_Main(void);
-PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_Head(void);
-PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_Next(PyInterpreterState *);
-PyAPI_FUNC(PyThreadState *) PyInterpreterState_ThreadHead(PyInterpreterState *);
-PyAPI_FUNC(PyThreadState *) PyThreadState_Next(PyThreadState *);
-
-typedef struct _frame *(*PyThreadFrameGetter)(PyThreadState *self_);
+#  define Py_CPYTHON_PYSTATE_H
+#  include  "cpython/pystate.h"
+#  undef Py_CPYTHON_PYSTATE_H
 #endif
 
 #ifdef __cplusplus