diff --git a/doc/lispref/internals.texi b/doc/lispref/internals.texi
index bccdca65e4e..da98283be80 100644
--- a/doc/lispref/internals.texi
+++ b/doc/lispref/internals.texi
@@ -1228,9 +1228,9 @@ the @var{runtime} structure with the value compiled into the module:
 
 @example
 int
-emacs_module_init (struct emacs_runtime *ert)
+emacs_module_init (struct emacs_runtime *runtime)
 @{
-  if (ert->size < sizeof (*ert))
+  if (ert->size < sizeof (*runtime))
     return 1;
 @}
 @end example
@@ -1247,7 +1247,7 @@ assumes it is part of the @code{emacs_module_init} function shown
 above:
 
 @example
-  emacs_env *env = ert->get_environment (ert);
+  emacs_env *env = ert->get_environment (runtime);
   if (env->size < sizeof (*env))
     return 2;
 @end example
@@ -1264,7 +1264,7 @@ Emacs, by comparing the size of the environment passed by Emacs with
 known sizes, like this:
 
 @example
-  emacs_env *env = ert->get_environment (ert);
+  emacs_env *env = ert->get_environment (runtime);
   if (env->size >= sizeof (struct emacs_env_26))
     emacs_version = 26;  /* Emacs 26 or later.  */
   else if (env->size >= sizeof (struct emacs_env_25))
@@ -1388,7 +1388,7 @@ Combining the above steps, code that arranges for a C function
 look like this, as part of the module initialization function:
 
 @example
- emacs_env *env = ert->get_environment (ert);
+ emacs_env *env = ert->get_environment (runtime);
  emacs_value func = env->make_function (env, min_arity, max_arity,
                                         module_func, docstring, data);
  emacs_value symbol = env->intern (env, "module-func");
@@ -1525,12 +1525,11 @@ This function returns the value of a Lisp float specified by
 @var{arg}, as a C @code{double} value.
 @end deftypefn
 
-@deftypefn Function struct timespec extract_time (emacs_env *@var{env}, emacs_value @var{time})
-This function, which is available since Emacs 27, interprets
-@var{time} as an Emacs Lisp time value and returns the corresponding
-@code{struct timespec}.  @xref{Time of Day}.  @code{struct timespec}
-represents a timestamp with nanosecond precision.  It has the
-following members:
+@deftypefn Function struct timespec extract_time (emacs_env *@var{env}, emacs_value @var{arg})
+This function, which is available since Emacs 27, interprets @var{arg}
+as an Emacs Lisp time value and returns the corresponding @code{struct
+timespec}.  @xref{Time of Day}.  @code{struct timespec} represents a
+timestamp with nanosecond precision.  It has the following members:
 
 @table @code
 @item time_t tv_sec
@@ -1728,9 +1727,9 @@ next_prime (emacs_env *env, ptrdiff_t nargs, emacs_value *args,
 @}
 
 int
-emacs_module_init (struct emacs_runtime *ert)
+emacs_module_init (struct emacs_runtime *runtime)
 @{
-  emacs_env *env = ert->get_environment (ert);
+  emacs_env *env = ert->get_environment (runtime);
   emacs_value symbol = env->intern (env, "next-prime");
   emacs_value func
     = env->make_function (env, 1, 1, next_prime, NULL, NULL);
@@ -1757,16 +1756,15 @@ there's no requirement that @var{time} be normalized.  This means that
 @code{@var{time}.tv_nsec} can be negative or larger than 999,999,999.
 @end deftypefn
 
-@deftypefn Function emacs_value make_string (emacs_env *@var{env}, const char *@var{str}, ptrdiff_t @var{strlen})
+@deftypefn Function emacs_value make_string (emacs_env *@var{env}, const char *@var{str}, ptrdiff_t @var{len})
 This function creates an Emacs string from C text string pointed by
 @var{str} whose length in bytes, not including the terminating null
-byte, is @var{strlen}.  The original string in @var{str} can be either
-an @acronym{ASCII} string or a UTF-8 encoded non-@acronym{ASCII}
-string; it can include embedded null bytes, and doesn't have to end in
-a terminating null byte at @code{@var{str}[@var{strlen}]}.  The
-function raises the @code{overflow-error} error condition if
-@var{strlen} is negative or exceeds the maximum length of an Emacs
-string.
+byte, is @var{len}.  The original string in @var{str} can be either an
+@acronym{ASCII} string or a UTF-8 encoded non-@acronym{ASCII} string;
+it can include embedded null bytes, and doesn't have to end in a
+terminating null byte at @code{@var{str}[@var{len}]}.  The function
+raises the @code{overflow-error} error condition if @var{len} is
+negative or exceeds the maximum length of an Emacs string.
 @end deftypefn
 
 The @acronym{API} does not provide functions to manipulate Lisp data
@@ -1823,25 +1821,27 @@ garbage-collected.  Don't run any expensive code in a finalizer,
 because GC must finish quickly to keep Emacs responsive.
 @end deftypefn
 
-@deftypefn Function void *get_user_ptr (emacs_env *@var{env}, emacs_value val)
+@deftypefn Function void *get_user_ptr (emacs_env *@var{env}, emacs_value @var{arg})
 This function extracts the C pointer from the Lisp object represented
-by @var{val}.
+by @var{arg}.
 @end deftypefn
 
-@deftypefn Function void set_user_ptr (emacs_env *@var{env}, emacs_value @var{value}, void *@var{ptr})
+@deftypefn Function void set_user_ptr (emacs_env *@var{env}, emacs_value @var{arg}, void *@var{ptr})
 This function sets the C pointer embedded in the @code{user-ptr}
-object represented by @var{value} to @var{ptr}.
+object represented by @var{arg} to @var{ptr}.
 @end deftypefn
 
-@deftypefn Function emacs_finalizer get_user_finalizer (emacs_env *@var{env}, emacs_value val)
+@deftypefn Function emacs_finalizer get_user_finalizer (emacs_env *@var{env}, emacs_value @var{arg})
 This function returns the finalizer of the @code{user-ptr} object
-represented by @var{val}, or @code{NULL} if it doesn't have a finalizer.
+represented by @var{arg}, or @code{NULL} if it doesn't have a
+finalizer.
 @end deftypefn
 
-@deftypefn Function void set_user_finalizer (emacs_env *@var{env}, emacs_value @var{val}, emacs_finalizer @var{fin})
+@deftypefn Function void set_user_finalizer (emacs_env *@var{env}, emacs_value @var{arg}, emacs_finalizer @var{fin})
 This function changes the finalizer of the @code{user-ptr} object
-represented by @var{val} to be @var{fin}.  If @var{fin} is a
-@code{NULL} pointer, the @code{user-ptr} object will have no finalizer.
+represented by @var{arg} to be @var{fin}.  If @var{fin} is a
+@code{NULL} pointer, the @code{user-ptr} object will have no
+finalizer.
 @end deftypefn
 
 @node Module Misc
@@ -1854,20 +1854,20 @@ be called via the @code{emacs_env} pointer.  Description of functions
 that were introduced after Emacs 25 calls out the first version where
 they became available.
 
-@deftypefn Function bool eq (emacs_env *@var{env}, emacs_value @var{val1}, emacs_value @var{val2})
+@deftypefn Function bool eq (emacs_env *@var{env}, emacs_value @var{a}, emacs_value @var{b})
 This function returns @code{true} if the Lisp objects represented by
-@var{val1} and @var{val2} are identical, @code{false} otherwise.  This
-is the same as the Lisp function @code{eq} (@pxref{Equality
-Predicates}), but avoids the need to intern the objects represented by
-the arguments.
+@var{a} and @var{b} are identical, @code{false} otherwise.  This is
+the same as the Lisp function @code{eq} (@pxref{Equality Predicates}),
+but avoids the need to intern the objects represented by the
+arguments.
 
 There are no @acronym{API} functions for other equality predicates, so
 you will need to use @code{intern} and @code{funcall}, described
 below, to perform more complex equality tests.
 @end deftypefn
 
-@deftypefn Function bool is_not_nil (emacs_env *@var{env}, emacs_value @var{val})
-This function tests whether the Lisp object represented by @var{val}
+@deftypefn Function bool is_not_nil (emacs_env *@var{env}, emacs_value @var{arg})
+This function tests whether the Lisp object represented by @var{arg}
 is non-@code{nil}; it returns @code{true} or @code{false} accordingly.
 
 Note that you could implement an equivalent test by using
@@ -1876,12 +1876,12 @@ then use @code{eq}, described above, to test for equality.  But using
 this function is more convenient.
 @end deftypefn
 
-@deftypefn Function emacs_value type_of (emacs_env *@var{env}, emacs_value @code{object})
-This function returns the type of @var{object} as a value that
-represents a symbol: @code{string} for a string, @code{integer} for an
-integer, @code{process} for a process, etc.  @xref{Type Predicates}.
-You can use @code{intern} and @code{eq} to compare against known type
-symbols, if your code needs to depend on the object type.
+@deftypefn Function emacs_value type_of (emacs_env *@var{env}, emacs_value @code{arg})
+This function returns the type of @var{arg} as a value that represents
+a symbol: @code{string} for a string, @code{integer} for an integer,
+@code{process} for a process, etc.  @xref{Type Predicates}.  You can
+use @code{intern} and @code{eq} to compare against known type symbols,
+if your code needs to depend on the object type.
 @end deftypefn
 
 @anchor{intern}
@@ -2055,11 +2055,12 @@ One use of this function is when you want to re-throw a non-local exit
 from one of the called @acronym{API} or Lisp functions.
 @end deftypefn
 
-@deftypefn Function void non_local_exit_signal (emacs_env *@var{env}, emacs_value @var{error}, emacs_value @var{data})
-This function signals the error represented by @var{error} with the
-specified error data @var{data}.  The module function should return
-soon after calling this function.  This function could be useful,
-e.g., for signaling errors from module functions to Emacs.
+@deftypefn Function void non_local_exit_signal (emacs_env *@var{env}, emacs_value @var{symbol}, emacs_value @var{data})
+This function signals the error represented by the error symbol
+@var{symbol} with the specified error data @var{data}.  The module
+function should return soon after calling this function.  This
+function could be useful, e.g., for signaling errors from module
+functions to Emacs.
 @end deftypefn
 
 
diff --git a/src/emacs-module.c b/src/emacs-module.c
index f2e3f627756..ff1a05450ce 100644
--- a/src/emacs-module.c
+++ b/src/emacs-module.c
@@ -126,7 +126,7 @@ typedef int (*emacs_init_function) (struct emacs_runtime *);
    should not throw C++ exceptions, so emacs-module.h declares the
    corresponding interfaces with EMACS_NOEXCEPT.  There is only C code
    in this module, though, so this constraint is not enforced here.  */
-typedef void (*emacs_finalizer_function) (void *);
+typedef void (*emacs_finalizer) (void *);
 
 
 /* Memory management.  */
@@ -343,11 +343,11 @@ CHECK_USER_PTR (Lisp_Object obj)
    the Emacs main thread.  */
 
 static emacs_env *
-module_get_environment (struct emacs_runtime *ert)
+module_get_environment (struct emacs_runtime *runtime)
 {
   module_assert_thread ();
-  module_assert_runtime (ert);
-  return ert->private_members->env;
+  module_assert_runtime (runtime);
+  return runtime->private_members->env;
 }
 
 /* To make global refs (GC-protected global values) keep a hash that
@@ -356,11 +356,11 @@ module_get_environment (struct emacs_runtime *ert)
 static Lisp_Object Vmodule_refs_hash;
 
 static emacs_value
-module_make_global_ref (emacs_env *env, emacs_value ref)
+module_make_global_ref (emacs_env *env, emacs_value value)
 {
   MODULE_FUNCTION_BEGIN (NULL);
   struct Lisp_Hash_Table *h = XHASH_TABLE (Vmodule_refs_hash);
-  Lisp_Object new_obj = value_to_lisp (ref), hashcode;
+  Lisp_Object new_obj = value_to_lisp (value), hashcode;
   ptrdiff_t i = hash_lookup (h, new_obj, &hashcode);
 
   if (i >= 0)
@@ -381,14 +381,14 @@ module_make_global_ref (emacs_env *env, emacs_value ref)
 }
 
 static void
-module_free_global_ref (emacs_env *env, emacs_value ref)
+module_free_global_ref (emacs_env *env, emacs_value global_value)
 {
   /* TODO: This probably never signals.  */
   /* FIXME: Wait a minute.  Shouldn't this function report an error if
      the hash lookup fails?  */
   MODULE_FUNCTION_BEGIN ();
   struct Lisp_Hash_Table *h = XHASH_TABLE (Vmodule_refs_hash);
-  Lisp_Object obj = value_to_lisp (ref);
+  Lisp_Object obj = value_to_lisp (global_value);
   ptrdiff_t i = hash_lookup (h, obj, NULL);
 
   if (i >= 0)
@@ -406,7 +406,7 @@ module_free_global_ref (emacs_env *env, emacs_value ref)
   if (module_assertions)
     {
       ptrdiff_t count = 0;
-      if (value_storage_contains_p (&global_storage, ref, &count))
+      if (value_storage_contains_p (&global_storage, global_value, &count))
         return;
       module_abort ("Global value was not found in list of %"pD"d globals",
                     count);
@@ -430,14 +430,15 @@ module_non_local_exit_clear (emacs_env *env)
 }
 
 static enum emacs_funcall_exit
-module_non_local_exit_get (emacs_env *env, emacs_value *sym, emacs_value *data)
+module_non_local_exit_get (emacs_env *env,
+                           emacs_value *symbol, emacs_value *data)
 {
   module_assert_thread ();
   module_assert_env (env);
   struct emacs_env_private *p = env->private_members;
   if (p->pending_non_local_exit != emacs_funcall_exit_return)
     {
-      *sym = &p->non_local_exit_symbol;
+      *symbol = &p->non_local_exit_symbol;
       *data = &p->non_local_exit_data;
     }
   return p->pending_non_local_exit;
@@ -445,12 +446,13 @@ module_non_local_exit_get (emacs_env *env, emacs_value *sym, emacs_value *data)
 
 /* Like for `signal', DATA must be a list.  */
 static void
-module_non_local_exit_signal (emacs_env *env, emacs_value sym, emacs_value data)
+module_non_local_exit_signal (emacs_env *env,
+                              emacs_value symbol, emacs_value data)
 {
   module_assert_thread ();
   module_assert_env (env);
   if (module_non_local_exit_check (env) == emacs_funcall_exit_return)
-    module_non_local_exit_signal_1 (env, value_to_lisp (sym),
+    module_non_local_exit_signal_1 (env, value_to_lisp (symbol),
 				    value_to_lisp (data));
 }
 
@@ -466,7 +468,7 @@ module_non_local_exit_throw (emacs_env *env, emacs_value tag, emacs_value value)
 
 /* Function prototype for the module Lisp functions.  */
 typedef emacs_value (*emacs_subr) (emacs_env *, ptrdiff_t,
-				   emacs_value [], void *);
+				   emacs_value *, void *);
 
 /* Module function.  */
 
@@ -503,8 +505,7 @@ allocate_module_function (void)
 
 static emacs_value
 module_make_function (emacs_env *env, ptrdiff_t min_arity, ptrdiff_t max_arity,
-		      emacs_subr subr, const char *documentation,
-		      void *data)
+		      emacs_subr func, const char *docstring, void *data)
 {
   MODULE_FUNCTION_BEGIN (NULL);
 
@@ -518,11 +519,11 @@ module_make_function (emacs_env *env, ptrdiff_t min_arity, ptrdiff_t max_arity,
   struct Lisp_Module_Function *function = allocate_module_function ();
   function->min_arity = min_arity;
   function->max_arity = max_arity;
-  function->subr = subr;
+  function->subr = func;
   function->data = data;
 
-  if (documentation)
-    function->documentation = build_string_from_utf8 (documentation);
+  if (docstring)
+    function->documentation = build_string_from_utf8 (docstring);
 
   Lisp_Object result;
   XSET_MODULE_FUNCTION (result, function);
@@ -532,8 +533,8 @@ module_make_function (emacs_env *env, ptrdiff_t min_arity, ptrdiff_t max_arity,
 }
 
 static emacs_value
-module_funcall (emacs_env *env, emacs_value fun, ptrdiff_t nargs,
-		emacs_value args[])
+module_funcall (emacs_env *env, emacs_value func, ptrdiff_t nargs,
+		emacs_value *args)
 {
   MODULE_FUNCTION_BEGIN (NULL);
 
@@ -545,7 +546,7 @@ module_funcall (emacs_env *env, emacs_value fun, ptrdiff_t nargs,
   if (INT_ADD_WRAPV (nargs, 1, &nargs1))
     overflow_error ();
   SAFE_ALLOCA_LISP (newargs, nargs1);
-  newargs[0] = value_to_lisp (fun);
+  newargs[0] = value_to_lisp (func);
   for (ptrdiff_t i = 0; i < nargs; i++)
     newargs[1 + i] = value_to_lisp (args[i]);
   emacs_value result = lisp_to_value (env, Ffuncall (nargs1, newargs));
@@ -561,17 +562,17 @@ module_intern (emacs_env *env, const char *name)
 }
 
 static emacs_value
-module_type_of (emacs_env *env, emacs_value value)
+module_type_of (emacs_env *env, emacs_value arg)
 {
   MODULE_FUNCTION_BEGIN (NULL);
-  return lisp_to_value (env, Ftype_of (value_to_lisp (value)));
+  return lisp_to_value (env, Ftype_of (value_to_lisp (arg)));
 }
 
 static bool
-module_is_not_nil (emacs_env *env, emacs_value value)
+module_is_not_nil (emacs_env *env, emacs_value arg)
 {
   MODULE_FUNCTION_BEGIN_NO_CATCH (false);
-  return ! NILP (value_to_lisp (value));
+  return ! NILP (value_to_lisp (arg));
 }
 
 static bool
@@ -582,14 +583,14 @@ module_eq (emacs_env *env, emacs_value a, emacs_value b)
 }
 
 static intmax_t
-module_extract_integer (emacs_env *env, emacs_value n)
+module_extract_integer (emacs_env *env, emacs_value arg)
 {
   MODULE_FUNCTION_BEGIN (0);
-  Lisp_Object l = value_to_lisp (n);
-  CHECK_INTEGER (l);
+  Lisp_Object lisp = value_to_lisp (arg);
+  CHECK_INTEGER (lisp);
   intmax_t i;
-  if (! integer_to_intmax (l, &i))
-    xsignal1 (Qoverflow_error, l);
+  if (! integer_to_intmax (lisp, &i))
+    xsignal1 (Qoverflow_error, lisp);
   return i;
 }
 
@@ -601,10 +602,10 @@ module_make_integer (emacs_env *env, intmax_t n)
 }
 
 static double
-module_extract_float (emacs_env *env, emacs_value f)
+module_extract_float (emacs_env *env, emacs_value arg)
 {
   MODULE_FUNCTION_BEGIN (0);
-  Lisp_Object lisp = value_to_lisp (f);
+  Lisp_Object lisp = value_to_lisp (arg);
   CHECK_TYPE (FLOATP (lisp), Qfloatp, lisp);
   return XFLOAT_DATA (lisp);
 }
@@ -617,8 +618,8 @@ module_make_float (emacs_env *env, double d)
 }
 
 static bool
-module_copy_string_contents (emacs_env *env, emacs_value value, char *buffer,
-			     ptrdiff_t *length)
+module_copy_string_contents (emacs_env *env, emacs_value value, char *buf,
+			     ptrdiff_t *len)
 {
   MODULE_FUNCTION_BEGIN (false);
   Lisp_Object lisp_str = value_to_lisp (value);
@@ -642,77 +643,77 @@ module_copy_string_contents (emacs_env *env, emacs_value value, char *buffer,
   ptrdiff_t raw_size = SBYTES (lisp_str_utf8);
   ptrdiff_t required_buf_size = raw_size + 1;
 
-  if (buffer == NULL)
+  if (buf == NULL)
     {
-      *length = required_buf_size;
+      *len = required_buf_size;
       return true;
     }
 
-  if (*length < required_buf_size)
+  if (*len < required_buf_size)
     {
-      ptrdiff_t actual = *length;
-      *length = required_buf_size;
+      ptrdiff_t actual = *len;
+      *len = required_buf_size;
       args_out_of_range_3 (INT_TO_INTEGER (actual),
                            INT_TO_INTEGER (required_buf_size),
                            INT_TO_INTEGER (PTRDIFF_MAX));
     }
 
-  *length = required_buf_size;
-  memcpy (buffer, SDATA (lisp_str_utf8), raw_size + 1);
+  *len = required_buf_size;
+  memcpy (buf, SDATA (lisp_str_utf8), raw_size + 1);
 
   return true;
 }
 
 static emacs_value
-module_make_string (emacs_env *env, const char *str, ptrdiff_t length)
+module_make_string (emacs_env *env, const char *str, ptrdiff_t len)
 {
   MODULE_FUNCTION_BEGIN (NULL);
-  if (! (0 <= length && length <= STRING_BYTES_BOUND))
+  if (! (0 <= len && len <= STRING_BYTES_BOUND))
     overflow_error ();
-  Lisp_Object lstr = make_string_from_utf8 (str, length);
+  Lisp_Object lstr = make_string_from_utf8 (str, len);
   return lisp_to_value (env, lstr);
 }
 
 static emacs_value
-module_make_user_ptr (emacs_env *env, emacs_finalizer_function fin, void *ptr)
+module_make_user_ptr (emacs_env *env, emacs_finalizer fin, void *ptr)
 {
   MODULE_FUNCTION_BEGIN (NULL);
   return lisp_to_value (env, make_user_ptr (fin, ptr));
 }
 
 static void *
-module_get_user_ptr (emacs_env *env, emacs_value uptr)
+module_get_user_ptr (emacs_env *env, emacs_value arg)
 {
   MODULE_FUNCTION_BEGIN (NULL);
-  Lisp_Object lisp = value_to_lisp (uptr);
+  Lisp_Object lisp = value_to_lisp (arg);
   CHECK_USER_PTR (lisp);
   return XUSER_PTR (lisp)->p;
 }
 
 static void
-module_set_user_ptr (emacs_env *env, emacs_value uptr, void *ptr)
+module_set_user_ptr (emacs_env *env, emacs_value arg, void *ptr)
 {
   MODULE_FUNCTION_BEGIN ();
-  Lisp_Object lisp = value_to_lisp (uptr);
+  Lisp_Object lisp = value_to_lisp (arg);
   CHECK_USER_PTR (lisp);
   XUSER_PTR (lisp)->p = ptr;
 }
 
-static emacs_finalizer_function
-module_get_user_finalizer (emacs_env *env, emacs_value uptr)
+static emacs_finalizer
+module_get_user_finalizer (emacs_env *env, emacs_value arg)
 {
   MODULE_FUNCTION_BEGIN (NULL);
-  Lisp_Object lisp = value_to_lisp (uptr);
+  Lisp_Object lisp = value_to_lisp (arg);
   CHECK_USER_PTR (lisp);
   return XUSER_PTR (lisp)->finalizer;
 }
 
 static void
-module_set_user_finalizer (emacs_env *env, emacs_value uptr,
-			   emacs_finalizer_function fin)
+module_set_user_finalizer (emacs_env *env, emacs_value arg,
+			   emacs_finalizer fin)
 {
   MODULE_FUNCTION_BEGIN ();
-  Lisp_Object lisp = value_to_lisp (uptr);
+  Lisp_Object lisp = value_to_lisp (arg);
   CHECK_USER_PTR (lisp);
   XUSER_PTR (lisp)->finalizer = fin;
 }
@@ -727,30 +728,31 @@ check_vec_index (Lisp_Object lvec, ptrdiff_t i)
 }
 
 static void
-module_vec_set (emacs_env *env, emacs_value vec, ptrdiff_t i, emacs_value val)
+module_vec_set (emacs_env *env, emacs_value vector, ptrdiff_t index,
+                emacs_value value)
 {
   MODULE_FUNCTION_BEGIN ();
-  Lisp_Object lvec = value_to_lisp (vec);
-  check_vec_index (lvec, i);
-  ASET (lvec, i, value_to_lisp (val));
+  Lisp_Object lisp = value_to_lisp (vector);
+  check_vec_index (lisp, index);
+  ASET (lisp, index, value_to_lisp (value));
 }
 
 static emacs_value
-module_vec_get (emacs_env *env, emacs_value vec, ptrdiff_t i)
+module_vec_get (emacs_env *env, emacs_value vector, ptrdiff_t index)
 {
   MODULE_FUNCTION_BEGIN (NULL);
-  Lisp_Object lvec = value_to_lisp (vec);
-  check_vec_index (lvec, i);
-  return lisp_to_value (env, AREF (lvec, i));
+  Lisp_Object lisp = value_to_lisp (vector);
+  check_vec_index (lisp, index);
+  return lisp_to_value (env, AREF (lisp, index));
 }
 
 static ptrdiff_t
-module_vec_size (emacs_env *env, emacs_value vec)
+module_vec_size (emacs_env *env, emacs_value vector)
 {
   MODULE_FUNCTION_BEGIN (0);
-  Lisp_Object lvec = value_to_lisp (vec);
-  CHECK_VECTOR (lvec);
-  return ASIZE (lvec);
+  Lisp_Object lisp = value_to_lisp (vector);
+  CHECK_VECTOR (lisp);
+  return ASIZE (lisp);
 }
 
 /* This function should return true if and only if maybe_quit would
@@ -771,10 +773,10 @@ module_process_input (emacs_env *env)
 }
 
 static struct timespec
-module_extract_time (emacs_env *env, emacs_value value)
+module_extract_time (emacs_env *env, emacs_value arg)
 {
   MODULE_FUNCTION_BEGIN ((struct timespec) {0});
-  return lisp_time_argument (value_to_lisp (value));
+  return lisp_time_argument (value_to_lisp (arg));
 }
 
 static emacs_value
@@ -1088,14 +1090,14 @@ module_assert_thread (void)
 }
 
 static void
-module_assert_runtime (struct emacs_runtime *ert)
+module_assert_runtime (struct emacs_runtime *runtime)
 {
   if (! module_assertions)
     return;
   ptrdiff_t count = 0;
   for (Lisp_Object tail = Vmodule_runtimes; CONSP (tail); tail = XCDR (tail))
     {
-      if (xmint_pointer (XCAR (tail)) == ert)
+      if (xmint_pointer (XCAR (tail)) == runtime)
         return;
       ++count;
     }
diff --git a/src/emacs-module.h.in b/src/emacs-module.h.in
index e9d5de495d6..4175240cd09 100644
--- a/src/emacs-module.h.in
+++ b/src/emacs-module.h.in
@@ -68,7 +68,7 @@ struct emacs_runtime
   struct emacs_runtime_private *private_members;
 
   /* Return an environment pointer.  */
-  emacs_env *(*get_environment) (struct emacs_runtime *ert)
+  emacs_env *(*get_environment) (struct emacs_runtime *runtime)
     EMACS_ATTRIBUTE_NONNULL(1);
 };
 
@@ -126,7 +126,7 @@ struct emacs_env_27
 };
 
 /* Every module should define a function as follows.  */
-extern int emacs_module_init (struct emacs_runtime *ert)
+extern int emacs_module_init (struct emacs_runtime *runtime)
   EMACS_NOEXCEPT
   EMACS_ATTRIBUTE_NONNULL(1);
 
diff --git a/src/module-env-25.h b/src/module-env-25.h
index d8f8eb68119..01ce65e9148 100644
--- a/src/module-env-25.h
+++ b/src/module-env-25.h
@@ -6,12 +6,10 @@
 
   /* Memory management.  */
 
-  emacs_value (*make_global_ref) (emacs_env *env,
-				  emacs_value any_reference)
+  emacs_value (*make_global_ref) (emacs_env *env, emacs_value value)
     EMACS_ATTRIBUTE_NONNULL(1);
 
-  void (*free_global_ref) (emacs_env *env,
-			   emacs_value global_reference)
+  void (*free_global_ref) (emacs_env *env, emacs_value global_value)
     EMACS_ATTRIBUTE_NONNULL(1);
 
   /* Non-local exit handling.  */
@@ -23,19 +21,15 @@
     EMACS_ATTRIBUTE_NONNULL(1);
 
   enum emacs_funcall_exit (*non_local_exit_get)
-    (emacs_env *env,
-     emacs_value *non_local_exit_symbol_out,
-     emacs_value *non_local_exit_data_out)
+    (emacs_env *env, emacs_value *symbol, emacs_value *data)
     EMACS_ATTRIBUTE_NONNULL(1, 2, 3);
 
   void (*non_local_exit_signal) (emacs_env *env,
-				 emacs_value non_local_exit_symbol,
-				 emacs_value non_local_exit_data)
+				 emacs_value symbol, emacs_value data)
     EMACS_ATTRIBUTE_NONNULL(1);
 
   void (*non_local_exit_throw) (emacs_env *env,
-				emacs_value tag,
-				emacs_value value)
+				emacs_value tag, emacs_value value)
     EMACS_ATTRIBUTE_NONNULL(1);
 
   /* Function registration.  */
@@ -43,48 +37,46 @@
   emacs_value (*make_function) (emacs_env *env,
 				ptrdiff_t min_arity,
 				ptrdiff_t max_arity,
-				emacs_value (*function) (emacs_env *env,
-							 ptrdiff_t nargs,
-							 emacs_value args[],
-							 void *)
+				emacs_value (*func) (emacs_env *env,
+                                                     ptrdiff_t nargs,
+                                                     emacs_value* args,
+                                                     void *data)
 				  EMACS_NOEXCEPT
                                   EMACS_ATTRIBUTE_NONNULL(1),
-				const char *documentation,
+				const char *docstring,
 				void *data)
     EMACS_ATTRIBUTE_NONNULL(1, 4);
 
   emacs_value (*funcall) (emacs_env *env,
-                          emacs_value function,
+                          emacs_value func,
                           ptrdiff_t nargs,
-                          emacs_value args[])
+                          emacs_value* args)
     EMACS_ATTRIBUTE_NONNULL(1);
 
-  emacs_value (*intern) (emacs_env *env,
-                         const char *symbol_name)
+  emacs_value (*intern) (emacs_env *env, const char *name)
     EMACS_ATTRIBUTE_NONNULL(1, 2);
 
   /* Type conversion.  */
 
-  emacs_value (*type_of) (emacs_env *env,
-			  emacs_value value)
+  emacs_value (*type_of) (emacs_env *env, emacs_value arg)
     EMACS_ATTRIBUTE_NONNULL(1);
 
-  bool (*is_not_nil) (emacs_env *env, emacs_value value)
+  bool (*is_not_nil) (emacs_env *env, emacs_value arg)
     EMACS_ATTRIBUTE_NONNULL(1);
 
   bool (*eq) (emacs_env *env, emacs_value a, emacs_value b)
     EMACS_ATTRIBUTE_NONNULL(1);
 
-  intmax_t (*extract_integer) (emacs_env *env, emacs_value value)
+  intmax_t (*extract_integer) (emacs_env *env, emacs_value arg)
     EMACS_ATTRIBUTE_NONNULL(1);
 
-  emacs_value (*make_integer) (emacs_env *env, intmax_t value)
+  emacs_value (*make_integer) (emacs_env *env, intmax_t n)
     EMACS_ATTRIBUTE_NONNULL(1);
 
-  double (*extract_float) (emacs_env *env, emacs_value value)
+  double (*extract_float) (emacs_env *env, emacs_value arg)
     EMACS_ATTRIBUTE_NONNULL(1);
 
-  emacs_value (*make_float) (emacs_env *env, double value)
+  emacs_value (*make_float) (emacs_env *env, double d)
     EMACS_ATTRIBUTE_NONNULL(1);
 
   /* Copy the content of the Lisp string VALUE to BUFFER as an utf8
@@ -101,13 +93,13 @@
 
   bool (*copy_string_contents) (emacs_env *env,
                                 emacs_value value,
-                                char *buffer,
-                                ptrdiff_t *size_inout)
+                                char *buf,
+                                ptrdiff_t *len)
     EMACS_ATTRIBUTE_NONNULL(1, 4);
 
   /* Create a Lisp string from a utf8 encoded string.  */
   emacs_value (*make_string) (emacs_env *env,
-			      const char *contents, ptrdiff_t length)
+			      const char *str, ptrdiff_t len)
     EMACS_ATTRIBUTE_NONNULL(1, 2);
 
   /* Embedded pointer type.  */
@@ -116,25 +108,24 @@
 				void *ptr)
     EMACS_ATTRIBUTE_NONNULL(1);
 
-  void *(*get_user_ptr) (emacs_env *env, emacs_value uptr)
+  void *(*get_user_ptr) (emacs_env *env, emacs_value arg)
     EMACS_ATTRIBUTE_NONNULL(1);
-  void (*set_user_ptr) (emacs_env *env, emacs_value uptr, void *ptr)
+  void (*set_user_ptr) (emacs_env *env, emacs_value arg, void *ptr)
     EMACS_ATTRIBUTE_NONNULL(1);
 
   void (*(*get_user_finalizer) (emacs_env *env, emacs_value uptr))
     (void *) EMACS_NOEXCEPT EMACS_ATTRIBUTE_NONNULL(1);
-  void (*set_user_finalizer) (emacs_env *env,
-			      emacs_value uptr,
+  void (*set_user_finalizer) (emacs_env *env, emacs_value arg,
 			      void (*fin) (void *) EMACS_NOEXCEPT)
     EMACS_ATTRIBUTE_NONNULL(1);
 
   /* Vector functions.  */
-  emacs_value (*vec_get) (emacs_env *env, emacs_value vec, ptrdiff_t i)
+  emacs_value (*vec_get) (emacs_env *env, emacs_value vector, ptrdiff_t index)
     EMACS_ATTRIBUTE_NONNULL(1);
 
-  void (*vec_set) (emacs_env *env, emacs_value vec, ptrdiff_t i,
-		   emacs_value val)
+  void (*vec_set) (emacs_env *env, emacs_value vector, ptrdiff_t index,
+		   emacs_value value)
     EMACS_ATTRIBUTE_NONNULL(1);
 
-  ptrdiff_t (*vec_size) (emacs_env *env, emacs_value vec)
+  ptrdiff_t (*vec_size) (emacs_env *env, emacs_value vector)
     EMACS_ATTRIBUTE_NONNULL(1);
diff --git a/src/module-env-27.h b/src/module-env-27.h
index 0fe2557d71b..9ef3c8b33bb 100644
--- a/src/module-env-27.h
+++ b/src/module-env-27.h
@@ -3,7 +3,7 @@
   enum emacs_process_input_result (*process_input) (emacs_env *env)
     EMACS_ATTRIBUTE_NONNULL (1);
 
-  struct timespec (*extract_time) (emacs_env *env, emacs_value value)
+  struct timespec (*extract_time) (emacs_env *env, emacs_value arg)
     EMACS_ATTRIBUTE_NONNULL (1);
 
   emacs_value (*make_time) (emacs_env *env, struct timespec time)