diff --git a/generator/format.py b/generator/format.py
index ab4ca34870..81deb56531 100644
--- a/generator/format.py
+++ b/generator/format.py
@@ -163,7 +163,7 @@ def __init__(self, name, typ, const, dflt, inpt, algo, doc):
                 # they are passed as (ptr, dim1, dim2)
                 if typ_cy == 'data_or_file':
                     decl_c = "double* {0}_p, size_t {0}_nrows,"\
-                        " size_t {0}_ncols, ssize_t {0}_layout".format(d4pname)
+                        " size_t {0}_ncols, Py_ssize_t {0}_layout".format(d4pname)
                     arg_c = "data_or_file({0}_p, {0}_ncols,"\
                         " {0}_nrows, {0}_layout)".format(d4pname)
                 # default values (see above pydefaults)
diff --git a/requirements-dev.txt b/requirements-dev.txt
index bfa239408c..b4b11d5b6d 100755
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -1,6 +1,8 @@
-Cython==0.29.24
-Jinja2==3.0.2
+Cython==0.29.24 ; python_version <= '3.9'
+Cython==0.29.25 ; python_version >= '3.10'
+Jinja2==3.0.3
 numpy==1.19.2 ; python_version <= '3.8'
-numpy==1.19.3 ; python_version >= '3.9'
+numpy==1.19.3 ; python_version == '3.9'
+numpy==1.21.3 ; python_version >= '3.10'
 pybind11==2.8.0
 cmake==3.21.3
diff --git a/src/daal4py.h b/src/daal4py.h
index 55e287f526..709b767bcb 100644
--- a/src/daal4py.h
+++ b/src/daal4py.h
@@ -171,7 +171,7 @@ struct data_or_file
     mutable daal::data_management::NumericTablePtr table;
     std::string                                    file;
     template<typename T>
-    inline data_or_file(T * ptr, size_t ncols, size_t nrows, ssize_t layout)
+    inline data_or_file(T * ptr, size_t ncols, size_t nrows, Py_ssize_t layout)
         : table(), file()
     {
         if(layout > 0) throw std::invalid_argument("Supporting only homogeneous, contiguous arrays.");
diff --git a/src/gettree.pyx b/src/gettree.pyx
index d881dfecd0..3186486a06 100644
--- a/src/gettree.pyx
+++ b/src/gettree.pyx
@@ -31,12 +31,12 @@ cdef extern from "daal4py.h":
 
 cdef extern from "tree_visitor.h":
     cdef struct skl_tree_node:
-        ssize_t left_child
-        ssize_t right_child
-        ssize_t feature
+        Py_ssize_t left_child
+        Py_ssize_t right_child
+        Py_ssize_t feature
         double threshold
         double impurity
-        ssize_t n_node_samples
+        Py_ssize_t n_node_samples
         double weighted_n_node_samples
 
     cdef struct TreeState:
diff --git a/src/tree_visitor.h b/src/tree_visitor.h
index de56b7e4e6..59788c32cb 100644
--- a/src/tree_visitor.h
+++ b/src/tree_visitor.h
@@ -29,12 +29,12 @@
 // cython will convert this struct into an numpy structured array
 // This is the layout that sklearn expects for its tree traversal mechanics
 struct skl_tree_node {
-    ssize_t left_child;
-    ssize_t right_child;
-    ssize_t feature;
+    Py_ssize_t left_child;
+    Py_ssize_t right_child;
+    Py_ssize_t feature;
     double threshold;
     double impurity;
-    ssize_t n_node_samples;
+    Py_ssize_t n_node_samples;
     double weighted_n_node_samples;
 
     skl_tree_node()
@@ -128,7 +128,7 @@ class toSKLearnTreeObjectVisitor : public TNVT<M>::visitor_type, public TreeStat
 
     size_t  node_id;
     size_t  max_n_classes;
-    std::vector<ssize_t> parents;
+    std::vector<Py_ssize_t> parents;
 };
 
 // This is the function for getting the tree state from a forest which we use in cython
@@ -199,7 +199,7 @@ bool NodeDepthCountNodeVisitor<M>::onSplitNode(const typename TNVT<M>::split_des
 template<typename M>
 toSKLearnTreeObjectVisitor<M>::toSKLearnTreeObjectVisitor(size_t _depth, size_t _n_nodes, size_t _n_leafs, size_t _max_n_classes)
     : node_id(0),
-      parents(arange<ssize_t>(-1, _depth-1))
+      parents(arange<Py_ssize_t>(-1, _depth-1))
 {
     max_n_classes = _max_n_classes;
     node_count = _n_nodes;
@@ -216,7 +216,7 @@ bool toSKLearnTreeObjectVisitor<M>::onSplitNode(const typename TNVT<M>::split_de
 {
     if(desc.level > 0) {
         // has parents
-        ssize_t parent = parents[desc.level - 1];
+        Py_ssize_t parent = parents[desc.level - 1];
         if(node_ar[parent].left_child > 0) {
             assert(node_ar[node_id].right_child < 0);
             node_ar[parent].right_child = node_id;
@@ -254,7 +254,7 @@ template<typename M>
 bool toSKLearnTreeObjectVisitor<M>::_onLeafNode(const daal::algorithms::tree_utils::NodeDescriptor &desc)
 {
     if(desc.level) {
-        ssize_t parent = parents[desc.level - 1];
+        Py_ssize_t parent = parents[desc.level - 1];
         if(node_ar[parent].left_child > 0) {
             assert(node_ar[node_id].right_child < 0);
             node_ar[parent].right_child = node_id;