diff --git a/pandas/_libs/join.pyx b/pandas/_libs/join.pyx
index cbe0e71153565..54892a7e4bc77 100644
--- a/pandas/_libs/join.pyx
+++ b/pandas/_libs/join.pyx
@@ -78,7 +78,7 @@ def inner_join(const int64_t[:] left, const int64_t[:] right,
 
 @cython.boundscheck(False)
 def left_outer_join(const int64_t[:] left, const int64_t[:] right,
-                    Py_ssize_t max_groups, sort=True):
+                    Py_ssize_t max_groups, bint sort=True):
     cdef:
         Py_ssize_t i, j, k, count = 0
         ndarray[int64_t] left_count, right_count, left_sorter, right_sorter
@@ -670,7 +670,7 @@ def asof_join_backward_on_X_by_Y(asof_t[:] left_values,
     cdef:
         Py_ssize_t left_pos, right_pos, left_size, right_size, found_right_pos
         ndarray[int64_t] left_indexer, right_indexer
-        bint has_tolerance = 0
+        bint has_tolerance = False
         asof_t tolerance_ = 0
         asof_t diff = 0
         HashTable hash_table
@@ -678,7 +678,7 @@ def asof_join_backward_on_X_by_Y(asof_t[:] left_values,
 
     # if we are using tolerance, set our objects
     if tolerance is not None:
-        has_tolerance = 1
+        has_tolerance = True
         tolerance_ = tolerance
 
     left_size = len(left_values)
@@ -739,7 +739,7 @@ def asof_join_forward_on_X_by_Y(asof_t[:] left_values,
     cdef:
         Py_ssize_t left_pos, right_pos, left_size, right_size, found_right_pos
         ndarray[int64_t] left_indexer, right_indexer
-        bint has_tolerance = 0
+        bint has_tolerance = False
         asof_t tolerance_ = 0
         asof_t diff = 0
         HashTable hash_table
@@ -747,7 +747,7 @@ def asof_join_forward_on_X_by_Y(asof_t[:] left_values,
 
     # if we are using tolerance, set our objects
     if tolerance is not None:
-        has_tolerance = 1
+        has_tolerance = True
         tolerance_ = tolerance
 
     left_size = len(left_values)
@@ -802,7 +802,7 @@ def asof_join_nearest_on_X_by_Y(asof_t[:] left_values,
                                 asof_t[:] right_values,
                                 by_t[:] left_by_values,
                                 by_t[:] right_by_values,
-                                bint allow_exact_matches=1,
+                                bint allow_exact_matches=True,
                                 tolerance=None):
 
     cdef:
@@ -853,19 +853,19 @@ def asof_join_nearest_on_X_by_Y(asof_t[:] left_values,
 
 def asof_join_backward(asof_t[:] left_values,
                        asof_t[:] right_values,
-                       bint allow_exact_matches=1,
+                       bint allow_exact_matches=True,
                        tolerance=None):
 
     cdef:
         Py_ssize_t left_pos, right_pos, left_size, right_size
         ndarray[int64_t] left_indexer, right_indexer
-        bint has_tolerance = 0
+        bint has_tolerance = False
         asof_t tolerance_ = 0
         asof_t diff = 0
 
     # if we are using tolerance, set our objects
     if tolerance is not None:
-        has_tolerance = 1
+        has_tolerance = True
         tolerance_ = tolerance
 
     left_size = len(left_values)
@@ -906,19 +906,19 @@ def asof_join_backward(asof_t[:] left_values,
 
 def asof_join_forward(asof_t[:] left_values,
                       asof_t[:] right_values,
-                      bint allow_exact_matches=1,
+                      bint allow_exact_matches=True,
                       tolerance=None):
 
     cdef:
         Py_ssize_t left_pos, right_pos, left_size, right_size
         ndarray[int64_t] left_indexer, right_indexer
-        bint has_tolerance = 0
+        bint has_tolerance = False
         asof_t tolerance_ = 0
         asof_t diff = 0
 
     # if we are using tolerance, set our objects
     if tolerance is not None:
-        has_tolerance = 1
+        has_tolerance = True
         tolerance_ = tolerance
 
     left_size = len(left_values)
@@ -960,7 +960,7 @@ def asof_join_forward(asof_t[:] left_values,
 
 def asof_join_nearest(asof_t[:] left_values,
                       asof_t[:] right_values,
-                      bint allow_exact_matches=1,
+                      bint allow_exact_matches=True,
                       tolerance=None):
 
     cdef: