diff --git a/src/App.tsx b/src/App.tsx
index 81e011f43..4542756bc 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -1,26 +1,289 @@
-/* eslint-disable max-len */
-/* eslint-disable jsx-a11y/control-has-associated-label */
-import React from 'react';
-import { UserWarning } from './UserWarning';
+import React, {
+  ChangeEvent,
+  useCallback,
+  useEffect,
+  useMemo,
+  useRef,
+  useState,
+} from 'react';
 
-const USER_ID = 0;
+import { UserWarning } from './UserWarning';
+import {
+  USER_ID,
+  deleteTodo,
+  getTodos,
+  updateTodo,
+  uploadTodo,
+} from './api/todos';
+import { Todo } from './types/Todo';
+import { TodoStatus } from './types/TodoStatus';
+import { ErrorType } from './types/Errors';
+import { Header } from './components/Header';
+import { TodoList } from './components/TodoList';
+import { Footer } from './components/Footer';
+import { emptyTodo } from './utils/EmptyTodo';
+import { UpdateTodoData } from './types/UpdateTodoData';
+import { ErrorNotification } from './components/ErrorNoti/ErrorNotiflication';
 
 export const App: React.FC = () => {
+  const [todos, setTodos] = useState<Todo[]>([]);
+  const [tempTodo, setTempTodo] = useState<Todo | null>(null);
+  const [todoTitle, setTodoTitle] = useState('');
+  const [isLoading, setIsLoading] = useState(false);
+  const [selectedTodoStatus, setSelectedTodoStatus] = useState(TodoStatus.All);
+  const [errorMessage, setErrorMessage] = useState<ErrorType | ''>('');
+  const [processingTodos, setProcessingTodos] = useState<number[]>([]);
+  const [editingTodoId, setEditingTodoId] = useState<number | null>(null);
+
+  const inputRef = useRef<HTMLInputElement | null>(null);
+
+  const focusInputField = () => inputRef.current?.focus();
+
+  useEffect(() => {
+    getTodos()
+      .then(setTodos)
+      .catch(() => setErrorMessage(ErrorType.LOAD_TODOS));
+  }, []);
+
+  useEffect(() => {
+    const timer = setTimeout(() => setErrorMessage(''), 3000);
+
+    return () => clearTimeout(timer);
+  }, [errorMessage]);
+
+  useEffect(focusInputField, [todoTitle, todos, selectedTodoStatus, isLoading]);
+
+  const filteringTodosByActiveStatus = useMemo(
+    () => todos.filter(todo => !todo.completed),
+    [todos],
+  );
+
+  const filteringTodosByCompletedStatus = useMemo(
+    () => todos.filter(todo => todo.completed),
+    [todos],
+  );
+
+  const filteredTodos = useMemo(() => {
+    switch (selectedTodoStatus) {
+      case TodoStatus.Active:
+        return filteringTodosByActiveStatus;
+
+      case TodoStatus.Completed:
+        return filteringTodosByCompletedStatus;
+
+      default:
+        return todos;
+    }
+  }, [
+    filteringTodosByActiveStatus,
+    filteringTodosByCompletedStatus,
+    selectedTodoStatus,
+    todos,
+  ]);
+
+  const changeTodoTitleHandler = useCallback(
+    (e: ChangeEvent<HTMLInputElement>) => {
+      setErrorMessage('');
+      setTodoTitle(e.target.value);
+    },
+    [],
+  );
+
+  const closeErrorHandler = () => setErrorMessage('');
+
+  const handleStatusChange = (status: TodoStatus) =>
+    setSelectedTodoStatus(status);
+
+  const selectedEditTodoId = (id: number | null) => setEditingTodoId(id);
+
+  const updateProcessingTodos = (id: number) =>
+    setProcessingTodos(prev => [...prev, id]);
+
+  const removeProcessingTodos = (id: number) =>
+    setProcessingTodos(prev => prev.filter(prevItem => prevItem !== id));
+
+  const addTodo = useCallback(
+    async (e: React.FormEvent<HTMLFormElement>) => {
+      e.preventDefault();
+      if (!todoTitle.trim()) {
+        setErrorMessage(ErrorType.EMPTY_TITLE);
+
+        return;
+      }
+
+      setIsLoading(true);
+      setErrorMessage('');
+      const newTempTodo: Todo = { ...emptyTodo, title: todoTitle.trim() };
+
+      setTempTodo(newTempTodo);
+      setProcessingTodos([newTempTodo.id]);
+
+      try {
+        const todo = await uploadTodo({
+          ...emptyTodo,
+          title: todoTitle.trim(),
+        });
+
+        setTodos(currentTodos => [...currentTodos, todo]);
+        setTodoTitle('');
+      } catch {
+        setErrorMessage(ErrorType.ADD_TODO);
+      } finally {
+        setIsLoading(false);
+        setTempTodo(null);
+        setProcessingTodos([]);
+        focusInputField();
+      }
+    },
+    [todoTitle],
+  );
+
+  const onDeleteTodo = useCallback((id: number) => {
+    deleteTodo(id)
+      .then(() =>
+        setTodos(currentTodos => currentTodos.filter(todo => todo.id !== id)),
+      )
+      .catch(() => setErrorMessage(ErrorType.DELETE_TODO))
+      .finally(() => {
+        removeProcessingTodos(id);
+        focusInputField();
+      });
+  }, []);
+
+  const removeTodo = useCallback(
+    (id: number) => {
+      setErrorMessage('');
+      updateProcessingTodos(id);
+      onDeleteTodo(id);
+    },
+    [onDeleteTodo],
+  );
+
+  const removeTodos = useCallback(async () => {
+    setIsLoading(true);
+    setErrorMessage('');
+
+    const deletePromises = filteringTodosByCompletedStatus.map(todo =>
+      removeTodo(todo.id),
+    );
+
+    await Promise.allSettled(deletePromises);
+    setIsLoading(false);
+  }, [filteringTodosByCompletedStatus, removeTodo]);
+
+  const onUpdateTodo = useCallback(async (id: number, data: UpdateTodoData) => {
+    return updateTodo(id, data)
+      .then(todo => {
+        setTodos(currentTodos => {
+          const newTodos = [...currentTodos];
+          const index = newTodos.findIndex(
+            findedTodo => findedTodo.id === todo.id,
+          );
+
+          newTodos.splice(index, 1, todo);
+
+          return newTodos;
+        });
+        setEditingTodoId(null);
+      })
+      .catch(() => {
+        setErrorMessage(ErrorType.UPDATE_TODO);
+        if ('title' in data) {
+          setEditingTodoId(id);
+          throw new Error();
+        }
+      })
+      .finally(() => {
+        removeProcessingTodos(id);
+        if (!('title' in data)) {
+          focusInputField();
+        }
+      });
+  }, []);
+
+  const toggleTodoStatus = useCallback(
+    (id: number, data: UpdateTodoData) => {
+      setErrorMessage('');
+      updateProcessingTodos(id);
+      onUpdateTodo(id, data);
+    },
+    [onUpdateTodo],
+  );
+
+  const toggleAll = useCallback(async () => {
+    setIsLoading(true);
+    setErrorMessage('');
+
+    let todosForChange: Todo[] = [];
+
+    if (filteringTodosByCompletedStatus.length !== todos.length) {
+      todosForChange = [...filteringTodosByActiveStatus];
+    } else {
+      todosForChange = [...todos];
+    }
+
+    const togglePromises = todosForChange.map(todo =>
+      toggleTodoStatus(todo.id, { completed: !todo.completed }),
+    );
+
+    await Promise.allSettled(togglePromises);
+    setIsLoading(false);
+  }, [
+    filteringTodosByActiveStatus,
+    filteringTodosByCompletedStatus.length,
+    todos,
+    toggleTodoStatus,
+  ]);
+
   if (!USER_ID) {
     return <UserWarning />;
   }
 
   return (
-    <section className="section container">
-      <p className="title is-4">
-        Copy all you need from the prev task:
-        <br />
-        <a href="https://github.com/mate-academy/react_todo-app-add-and-delete#react-todo-app-add-and-delete">
-          React Todo App - Add and Delete
-        </a>
-      </p>
-
-      <p className="subtitle">Styles are already copied</p>
-    </section>
+    <div className="todoapp">
+      <h1 className="todoapp__title">todos</h1>
+
+      <div className="todoapp__content">
+        <Header
+          todos={todos}
+          value={todoTitle}
+          addTodo={addTodo}
+          onChange={changeTodoTitleHandler}
+          inputRef={inputRef}
+          isLoading={isLoading}
+          completedTodosCount={filteringTodosByCompletedStatus.length}
+          toggleAll={toggleAll}
+        />
+        <TodoList
+          preparedTodos={filteredTodos}
+          processingTodos={processingTodos}
+          tempTodo={tempTodo}
+          removeTodo={removeTodo}
+          toggleTodoStatus={toggleTodoStatus}
+          errorMessage={errorMessage}
+          editingTodoId={editingTodoId}
+          selectedEditTodoId={selectedEditTodoId}
+          onUpdateTodo={onUpdateTodo}
+          updateProcessingTodos={updateProcessingTodos}
+          removeProcessingTodos={removeProcessingTodos}
+        />
+
+        <Footer
+          todos={todos}
+          selectedStatus={selectedTodoStatus}
+          onStatusChange={handleStatusChange}
+          filteringTodosByActiveStatus={filteringTodosByActiveStatus.length}
+          filteringTodosByCompletedStatus={
+            filteringTodosByCompletedStatus.length
+          }
+          removeTodos={removeTodos}
+        />
+      </div>
+
+      <ErrorNotification
+        errorMessage={errorMessage}
+        closeErrorHandler={closeErrorHandler}
+      />
+    </div>
   );
 };
diff --git a/src/api/todos.ts b/src/api/todos.ts
new file mode 100644
index 000000000..2e798c81d
--- /dev/null
+++ b/src/api/todos.ts
@@ -0,0 +1,21 @@
+import { Todo } from '../types/Todo';
+import { client } from '../utils/fetchClient';
+import { UpdateTodoData } from '../types/UpdateTodoData';
+
+export const USER_ID = 337;
+
+export const getTodos = () => {
+  return client.get<Todo[]>(`/todos?userId=${USER_ID}`);
+};
+
+export const uploadTodo = ({ completed, title, userId }: Omit<Todo, 'id'>) => {
+  return client.post<Todo>('/todos', { completed, title, userId });
+};
+
+export const deleteTodo = (id: number) => {
+  return client.delete(`/todos/${id}`);
+};
+
+export const updateTodo = (id: number, data: UpdateTodoData) => {
+  return client.patch<Todo>(`/todos/${id}`, data);
+};
diff --git a/src/components/ErrorNoti/ErrorNotiflication.tsx b/src/components/ErrorNoti/ErrorNotiflication.tsx
new file mode 100644
index 000000000..0cb1d1f4d
--- /dev/null
+++ b/src/components/ErrorNoti/ErrorNotiflication.tsx
@@ -0,0 +1,29 @@
+import classNames from 'classnames';
+
+type Props = {
+  errorMessage: string;
+  closeErrorHandler: () => void;
+};
+
+export const ErrorNotification: React.FC<Props> = ({
+  errorMessage,
+  closeErrorHandler,
+}) => {
+  return (
+    <div
+      data-cy="ErrorNotification"
+      className={classNames(
+        'notification is-danger is-light has-text-weight-normal',
+        { hidden: errorMessage.length === 0 },
+      )}
+    >
+      <button
+        data-cy="HideErrorButton"
+        type="button"
+        className="delete"
+        onClick={closeErrorHandler}
+      />
+      {errorMessage}
+    </div>
+  );
+};
diff --git a/src/components/ErrorNoti/index.ts b/src/components/ErrorNoti/index.ts
new file mode 100644
index 000000000..e69de29bb
diff --git a/src/components/Footer/Footer.tsx b/src/components/Footer/Footer.tsx
new file mode 100644
index 000000000..f67efca42
--- /dev/null
+++ b/src/components/Footer/Footer.tsx
@@ -0,0 +1,63 @@
+import React from 'react';
+
+import { TodoStatus } from '../../types/TodoStatus';
+import { Todo } from '../../types/Todo';
+import { TodoStatusRoutes } from '../../constants/TodoRoutes';
+
+import classNames from 'classnames';
+
+type Props = {
+  todos: Todo[];
+  selectedStatus: TodoStatus;
+  onStatusChange: (status: TodoStatus) => void;
+  filteringTodosByActiveStatus: number;
+  filteringTodosByCompletedStatus: number;
+  removeTodos: () => void;
+};
+
+export const Footer: React.FC<Props> = ({
+  todos,
+  selectedStatus,
+  onStatusChange,
+  filteringTodosByActiveStatus,
+  filteringTodosByCompletedStatus,
+  removeTodos,
+}) => {
+  if (todos.length > 0) {
+    return (
+      <footer className="todoapp__footer" data-cy="Footer">
+        <span className="todo-count" data-cy="TodosCounter">
+          {filteringTodosByActiveStatus} items left
+        </span>
+
+        <nav className="filter" data-cy="Filter">
+          {Object.keys(TodoStatusRoutes).map(status => (
+            <a
+              key={status}
+              href={`#${TodoStatusRoutes[status as TodoStatus]}`}
+              className={classNames('filter__link', {
+                selected: selectedStatus === status,
+              })}
+              data-cy={`FilterLink${status}`}
+              onClick={() => onStatusChange(status as TodoStatus)}
+            >
+              {status}
+            </a>
+          ))}
+        </nav>
+
+        <button
+          type="button"
+          className="todoapp__clear-completed"
+          data-cy="ClearCompletedButton"
+          disabled={!filteringTodosByCompletedStatus}
+          onClick={removeTodos}
+        >
+          Clear completed
+        </button>
+      </footer>
+    );
+  } else {
+    return null;
+  }
+};
diff --git a/src/components/Footer/index.ts b/src/components/Footer/index.ts
new file mode 100644
index 000000000..ddcc5a9cd
--- /dev/null
+++ b/src/components/Footer/index.ts
@@ -0,0 +1 @@
+export * from './Footer';
diff --git a/src/components/Form/Form.tsx b/src/components/Form/Form.tsx
new file mode 100644
index 000000000..c875ad645
--- /dev/null
+++ b/src/components/Form/Form.tsx
@@ -0,0 +1,43 @@
+import { ChangeEvent, KeyboardEvent, RefObject } from 'react';
+
+type Props = {
+  value: string;
+  onChange: (e: ChangeEvent<HTMLInputElement>) => void;
+  inputRef?: RefObject<HTMLInputElement>;
+  isLoading?: boolean;
+  addTodo?: (e: React.FormEvent<HTMLFormElement>) => void;
+  onBlur?: () => void;
+  onCancel?: (e: KeyboardEvent<HTMLInputElement>) => void;
+  classNames?: string;
+  dataCy?: string;
+};
+
+export const Form: React.FC<Props> = ({
+  addTodo,
+  value,
+  onChange,
+  inputRef = null,
+  isLoading = false,
+  onBlur = () => {},
+  onCancel = () => {},
+  classNames,
+  dataCy = 'NewTodoField',
+}) => {
+  return (
+    <form onSubmit={addTodo}>
+      <input
+        data-cy={dataCy}
+        type="text"
+        className={classNames}
+        placeholder="What needs to be done?"
+        value={value}
+        onChange={onChange}
+        ref={inputRef}
+        disabled={isLoading}
+        onKeyUp={onCancel}
+        autoFocus
+        onBlur={onBlur}
+      />
+    </form>
+  );
+};
diff --git a/src/components/Form/index.ts b/src/components/Form/index.ts
new file mode 100644
index 000000000..b690c60a1
--- /dev/null
+++ b/src/components/Form/index.ts
@@ -0,0 +1 @@
+export * from './Form';
diff --git a/src/components/Header/Header.tsx b/src/components/Header/Header.tsx
new file mode 100644
index 000000000..69ba2e78d
--- /dev/null
+++ b/src/components/Header/Header.tsx
@@ -0,0 +1,51 @@
+import React, { RefObject } from 'react';
+import { Todo } from '../../types/Todo';
+
+import classNames from 'classnames';
+import { Form } from '../Form';
+
+type Props = {
+  todos: Todo[];
+  addTodo: (e: React.FormEvent<HTMLFormElement>) => void;
+  onChange: (e: React.ChangeEvent<HTMLInputElement>) => void;
+  inputRef: RefObject<HTMLInputElement>;
+  isLoading: boolean;
+  value: string;
+  completedTodosCount: number;
+  toggleAll: () => void;
+};
+
+export const Header: React.FC<Props> = ({
+  todos,
+  addTodo,
+  onChange,
+  inputRef,
+  isLoading,
+  value,
+  completedTodosCount,
+  toggleAll,
+}) => {
+  return (
+    <header className="todoapp__header">
+      {!!todos.length && (
+        <button
+          type="button"
+          className={classNames('todoapp__toggle-all', {
+            active: completedTodosCount === todos.length,
+          })}
+          data-cy="ToggleAllButton"
+          onClick={toggleAll}
+        />
+      )}
+
+      <Form
+        addTodo={addTodo}
+        value={value}
+        onChange={onChange}
+        inputRef={inputRef}
+        isLoading={isLoading}
+        classNames="todoapp__new-todo"
+      />
+    </header>
+  );
+};
diff --git a/src/components/Header/index.ts b/src/components/Header/index.ts
new file mode 100644
index 000000000..266dec8a1
--- /dev/null
+++ b/src/components/Header/index.ts
@@ -0,0 +1 @@
+export * from './Header';
diff --git a/src/components/TodoItem/TodoItem.tsx b/src/components/TodoItem/TodoItem.tsx
new file mode 100644
index 000000000..48985c8ec
--- /dev/null
+++ b/src/components/TodoItem/TodoItem.tsx
@@ -0,0 +1,155 @@
+import React, {
+  FormEvent,
+  KeyboardEvent,
+  useCallback,
+  useRef,
+  useState,
+} from 'react';
+
+import { Todo } from '../../types/Todo';
+import { UpdateTodoData } from '../../types/UpdateTodoData';
+import { Form } from './../Form';
+
+import classNames from 'classnames';
+
+type Props<T> = {
+  todo: T;
+  isActive: boolean;
+  removeTodo?: (id: number) => void;
+  toggleTodoStatus?: () => void;
+  onUpdateTodo?: (id: number, data: UpdateTodoData) => Promise<void>;
+  updateProcessingTodos?: (id: number) => void;
+  removeProcessingTodos?: (id: number) => void;
+};
+
+export const TodoItem: React.FC<Props<Todo>> = ({
+  todo,
+  isActive,
+  removeTodo = () => {},
+  toggleTodoStatus = () => {},
+  onUpdateTodo,
+  updateProcessingTodos,
+  removeProcessingTodos,
+}) => {
+  const { completed, id, title } = todo;
+
+  const [formActive, setFormActive] = useState<boolean>(false);
+  const [todoTitle, setTodoTitle] = useState<string>('');
+  const inputRef = useRef<HTMLInputElement>(null);
+
+  const dbClickHandler = () => {
+    setFormActive(true);
+    setTodoTitle(title);
+  };
+
+  const onEdit = useCallback(async () => {
+    if (!todoTitle.length) {
+      removeTodo?.(id);
+
+      return;
+    }
+
+    updateProcessingTodos?.(id);
+
+    if (todoTitle !== title) {
+      onUpdateTodo?.(id, { title: todoTitle.trim() })
+        .then(() => setFormActive(false))
+        .catch(() => {
+          if (inputRef.current) {
+            inputRef.current.focus();
+          }
+        })
+        .finally(() => removeProcessingTodos?.(id));
+    } else if (todoTitle === title) {
+      setFormActive(false);
+    }
+  }, [id, title, todoTitle]);
+
+  const onEditHandler = (event: FormEvent<HTMLFormElement>) => {
+    event.preventDefault();
+
+    onEdit();
+  };
+
+  const onBlurHandler = () => {
+    onEdit();
+  };
+
+  const removeTodoHandler = () => {
+    removeTodo?.(id);
+  };
+
+  const keyUpHandler = useCallback(
+    (e: KeyboardEvent<HTMLInputElement>) => {
+      if (e.key === 'Escape') {
+        setFormActive(false);
+        setTodoTitle(title);
+        removeProcessingTodos?.(id);
+      }
+    },
+    [id, removeProcessingTodos, title],
+  );
+
+  return (
+    <div
+      data-cy="Todo"
+      className={classNames('todo', {
+        completed: completed,
+        'temp-item-enter temp-item-enter-active': id === 0,
+      })}
+      key={id}
+    >
+      {/* eslint-disable-next-line jsx-a11y/label-has-associated-control*/}
+      <label className="todo__status-label">
+        <input
+          data-cy="TodoStatus"
+          type="checkbox"
+          className="todo__status"
+          checked={completed}
+          onChange={toggleTodoStatus}
+        />
+      </label>
+
+      {formActive ? (
+        <Form
+          addTodo={onEditHandler}
+          value={todoTitle}
+          onChange={e => setTodoTitle(e.target.value)}
+          onBlur={onBlurHandler}
+          onCancel={e => keyUpHandler(e)}
+          inputRef={inputRef}
+          classNames="todo__title-field"
+          dataCy="TodoTitleField"
+        />
+      ) : (
+        <>
+          <span
+            onDoubleClick={dbClickHandler}
+            data-cy="TodoTitle"
+            className="todo__title"
+          >
+            {title}
+          </span>
+          <button
+            type="button"
+            className="todo__remove"
+            data-cy="TodoDelete"
+            onClick={removeTodoHandler}
+          >
+            ×
+          </button>
+        </>
+      )}
+
+      <div
+        data-cy="TodoLoader"
+        className={classNames('modal overlay', {
+          'is-active': isActive,
+        })}
+      >
+        <div className="modal-background has-background-white-ter" />
+        {isActive && <div className="loader" />}
+      </div>
+    </div>
+  );
+};
diff --git a/src/components/TodoItem/index.ts b/src/components/TodoItem/index.ts
new file mode 100644
index 000000000..21f4abac3
--- /dev/null
+++ b/src/components/TodoItem/index.ts
@@ -0,0 +1 @@
+export * from './TodoItem';
diff --git a/src/components/TodoList/TodoList.tsx b/src/components/TodoList/TodoList.tsx
new file mode 100644
index 000000000..52b3a91da
--- /dev/null
+++ b/src/components/TodoList/TodoList.tsx
@@ -0,0 +1,58 @@
+import React from 'react';
+import { Todo } from '../../types/Todo';
+import { TodoItem } from '../TodoItem/TodoItem';
+import { CSSTransition, TransitionGroup } from 'react-transition-group';
+import { UpdateTodoData } from '../../types/UpdateTodoData';
+import { ErrorType } from '../../types/Errors';
+
+type Props = {
+  preparedTodos: Todo[];
+  processingTodos: number[];
+  tempTodo: Todo | null;
+  removeTodo: (id: number) => void;
+  toggleTodoStatus: (id: number, data: UpdateTodoData) => void;
+  errorMessage: ErrorType | '';
+  editingTodoId: number | null;
+  selectedEditTodoId: (id: number | null) => void;
+  onUpdateTodo: (id: number, data: UpdateTodoData) => Promise<void>;
+  updateProcessingTodos: (id: number) => void;
+  removeProcessingTodos: (id: number) => void;
+};
+
+export const TodoList: React.FC<Props> = ({
+  preparedTodos,
+  processingTodos,
+  tempTodo,
+  removeTodo,
+  toggleTodoStatus,
+  onUpdateTodo,
+  updateProcessingTodos,
+  removeProcessingTodos,
+}) => {
+  return (
+    <section className="todoapp__main" data-cy="TodoList">
+      <TransitionGroup>
+        {preparedTodos.map(todo => (
+          <CSSTransition key={todo.id} timeout={300} classNames="item">
+            <TodoItem
+              todo={todo}
+              isActive={processingTodos.includes(todo.id)}
+              removeTodo={() => removeTodo(todo.id)}
+              toggleTodoStatus={() =>
+                toggleTodoStatus(todo.id, { completed: !todo.completed })
+              }
+              onUpdateTodo={onUpdateTodo}
+              updateProcessingTodos={updateProcessingTodos}
+              removeProcessingTodos={removeProcessingTodos}
+            />
+          </CSSTransition>
+        ))}
+        {tempTodo && (
+          <CSSTransition key={0} timeout={300} classNames="temp-item">
+            <TodoItem todo={tempTodo} isActive={true} />
+          </CSSTransition>
+        )}
+      </TransitionGroup>
+    </section>
+  );
+};
diff --git a/src/components/TodoList/index.ts b/src/components/TodoList/index.ts
new file mode 100644
index 000000000..f239f4345
--- /dev/null
+++ b/src/components/TodoList/index.ts
@@ -0,0 +1 @@
+export * from './TodoList';
diff --git a/src/constants/TodoRoutes.tsx b/src/constants/TodoRoutes.tsx
new file mode 100644
index 000000000..566f59022
--- /dev/null
+++ b/src/constants/TodoRoutes.tsx
@@ -0,0 +1,7 @@
+import { TodoStatus } from '../types/TodoStatus';
+
+export const TodoStatusRoutes: Record<TodoStatus, string> = {
+  [TodoStatus.All]: '/',
+  [TodoStatus.Active]: '/active',
+  [TodoStatus.Completed]: '/completed',
+};
diff --git a/src/types/Errors.ts b/src/types/Errors.ts
new file mode 100644
index 000000000..098219054
--- /dev/null
+++ b/src/types/Errors.ts
@@ -0,0 +1,7 @@
+export enum ErrorType {
+  LOAD_TODOS = 'Unable to load todos',
+  ADD_TODO = 'Unable to add a todo',
+  DELETE_TODO = 'Unable to delete a todo',
+  UPDATE_TODO = 'Unable to update a todo',
+  EMPTY_TITLE = 'Title should not be empty',
+}
diff --git a/src/types/Todo.ts b/src/types/Todo.ts
new file mode 100644
index 000000000..d9643b6d7
--- /dev/null
+++ b/src/types/Todo.ts
@@ -0,0 +1,14 @@
+import { USER_ID } from '../api/todos';
+
+export interface Todo {
+  id: number;
+  title: string;
+  completed: boolean;
+  userId: number;
+}
+
+export const emptyTodo: Omit<Todo, 'id'> = {
+  completed: false,
+  userId: USER_ID,
+  title: '',
+};
diff --git a/src/types/TodoStatus.ts b/src/types/TodoStatus.ts
new file mode 100644
index 000000000..5a7e0d2f7
--- /dev/null
+++ b/src/types/TodoStatus.ts
@@ -0,0 +1,5 @@
+export enum TodoStatus {
+  Active = 'Active',
+  Completed = 'Completed',
+  All = 'All',
+}
diff --git a/src/types/UpdateTodoData.ts b/src/types/UpdateTodoData.ts
new file mode 100644
index 000000000..ab50171c1
--- /dev/null
+++ b/src/types/UpdateTodoData.ts
@@ -0,0 +1,3 @@
+import { Todo } from './Todo';
+
+export type UpdateTodoData = Partial<Omit<Todo, 'id' | 'userId'>>;
diff --git a/src/utils/EmptyTodo.tsx b/src/utils/EmptyTodo.tsx
new file mode 100644
index 000000000..5f22b2731
--- /dev/null
+++ b/src/utils/EmptyTodo.tsx
@@ -0,0 +1,9 @@
+import { Todo } from '../types/Todo';
+import { USER_ID } from '../api/todos';
+
+export const emptyTodo: Todo = {
+  id: 0,
+  completed: false,
+  userId: USER_ID,
+  title: '',
+};
diff --git a/src/utils/fetchClient.ts b/src/utils/fetchClient.ts
new file mode 100644
index 000000000..708ac4c17
--- /dev/null
+++ b/src/utils/fetchClient.ts
@@ -0,0 +1,46 @@
+/* eslint-disable @typescript-eslint/no-explicit-any */
+const BASE_URL = 'https://mate.academy/students-api';
+
+// returns a promise resolved after a given delay
+function wait(delay: number) {
+  return new Promise(resolve => {
+    setTimeout(resolve, delay);
+  });
+}
+
+// To have autocompletion and avoid mistypes
+type RequestMethod = 'GET' | 'POST' | 'PATCH' | 'DELETE';
+
+function request<T>(
+  url: string,
+  method: RequestMethod = 'GET',
+  data: any = null, // we can send any data to the server
+): Promise<T> {
+  const options: RequestInit = { method };
+
+  if (data) {
+    // We add body and Content-Type only for the requests with data
+    options.body = JSON.stringify(data);
+    options.headers = {
+      'Content-Type': 'application/json; charset=UTF-8',
+    };
+  }
+
+  // DON'T change the delay it is required for tests
+  return wait(100)
+    .then(() => fetch(BASE_URL + url, options))
+    .then(response => {
+      if (!response.ok) {
+        throw new Error();
+      }
+
+      return response.json();
+    });
+}
+
+export const client = {
+  get: <T>(url: string) => request<T>(url),
+  post: <T>(url: string, data: any) => request<T>(url, 'POST', data),
+  patch: <T>(url: string, data: any) => request<T>(url, 'PATCH', data),
+  delete: (url: string) => request(url, 'DELETE'),
+};
diff --git a/src/utils/helpers.tsx b/src/utils/helpers.tsx
new file mode 100644
index 000000000..d01dac56d
--- /dev/null
+++ b/src/utils/helpers.tsx
@@ -0,0 +1,18 @@
+import { Todo } from '../types/Todo';
+import { TodoStatus } from '../types/TodoStatus';
+
+export const filterTodosByStatus = (
+  todos: Todo[],
+  status: TodoStatus,
+): Todo[] => {
+  switch (status) {
+    case TodoStatus.Active:
+      return todos.filter(todo => !todo.completed);
+
+    case TodoStatus.Completed:
+      return todos.filter(todo => todo.completed);
+
+    default:
+      return todos;
+  }
+};