diff --git a/README.md b/README.md
index 47a1add059..c4c38b19a1 100644
--- a/README.md
+++ b/README.md
@@ -47,4 +47,4 @@ Implement the ability to edit a todo title on double click:
 
 - Implement a solution following the [React task guideline](https://github.com/mate-academy/react_task-guideline#react-tasks-guideline).
 - Use the [React TypeScript cheat sheet](https://mate-academy.github.io/fe-program/js/extra/react-typescript).
-- Replace `<your_account>` with your Github username in the [DEMO LINK](https://<your_account>.github.io/react_todo-app-with-api/) and add it to the PR description.
+- Replace `<your_account>` with your Github username in the [DEMO LINK](https://wiolip.github.io/react_todo-app-with-api/) and add it to the PR description.
diff --git a/package-lock.json b/package-lock.json
index 19701e8788..0dbc74a8e1 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -19,7 +19,7 @@
       },
       "devDependencies": {
         "@cypress/react18": "^2.0.1",
-        "@mate-academy/scripts": "^1.8.5",
+        "@mate-academy/scripts": "^2.1.3",
         "@mate-academy/students-ts-config": "*",
         "@mate-academy/stylelint-config": "*",
         "@types/node": "^20.14.10",
@@ -1183,10 +1183,11 @@
       }
     },
     "node_modules/@mate-academy/scripts": {
-      "version": "1.8.5",
-      "resolved": "https://registry.npmjs.org/@mate-academy/scripts/-/scripts-1.8.5.tgz",
-      "integrity": "sha512-mHRY2FkuoYCf5U0ahIukkaRo5LSZsxrTSgMJheFoyf3VXsTvfM9OfWcZIDIDB521kdPrScHHnRp+JRNjCfUO5A==",
+      "version": "2.1.3",
+      "resolved": "https://registry.npmjs.org/@mate-academy/scripts/-/scripts-2.1.3.tgz",
+      "integrity": "sha512-a07wHTj/1QUK2Aac5zHad+sGw4rIvcNl5lJmJpAD7OxeSbnCdyI6RXUHwXhjF5MaVo9YHrJ0xVahyERS2IIyBQ==",
       "dev": true,
+      "license": "MIT",
       "dependencies": {
         "@octokit/rest": "^17.11.2",
         "@types/get-port": "^4.2.0",
diff --git a/package.json b/package.json
index b6062525ab..6d0f20adcc 100644
--- a/package.json
+++ b/package.json
@@ -15,7 +15,7 @@
   },
   "devDependencies": {
     "@cypress/react18": "^2.0.1",
-    "@mate-academy/scripts": "^1.8.5",
+    "@mate-academy/scripts": "^2.1.3",
     "@mate-academy/students-ts-config": "*",
     "@mate-academy/stylelint-config": "*",
     "@types/node": "^20.14.10",
diff --git a/src/App.tsx b/src/App.tsx
index 81e011f432..80deef56bc 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -1,26 +1,282 @@
-/* eslint-disable max-len */
+/* eslint-disable jsx-a11y/label-has-associated-control */
 /* eslint-disable jsx-a11y/control-has-associated-label */
-import React from 'react';
+import React, {
+  useCallback,
+  useEffect,
+  useMemo,
+  useRef,
+  useState,
+} from 'react';
+import classNames from 'classnames';
 import { UserWarning } from './UserWarning';
-
-const USER_ID = 0;
+import {
+  getTodos,
+  createTodo,
+  deleteTodo,
+  USER_ID,
+  updateTodo,
+} from './api/todos';
+import { NewTodoForm } from './components/NewTodoForm';
+import { Todo } from './types/Todo';
+import { TodoList } from './components/TodoList';
+import { Filter, FILTERS } from './types/Filters';
+import { ErrorNotification } from './components/ErrorNotification';
+import { FilterComponent } from './components/FilterComponent';
 
 export const App: React.FC = () => {
+  const [todos, setTodos] = useState<Todo[]>([]);
+  const [tempTodo, setTempTodo] = useState<Todo | null>(null);
+  const [loadingIds, setLoadingIds] = useState<number[]>([]);
+  const [filter, setFilter] = useState<Filter>('all');
+  const [error, setError] = useState<string | null>(null);
+
+  const todoFieldRef = useRef<HTMLInputElement>(null);
+  const errorTimeoutRef = useRef<number | null>(null);
+
+  // Focus the input field
+  const focusField = useCallback(() => {
+    todoFieldRef.current?.focus();
+  }, []);
+
+  // Refocus input whenever temporary todo changes
+  useEffect(() => {
+    focusField();
+  }, [tempTodo, focusField]);
+
+  // Display error message and hide it automatically after 3 seconds
+  const showError = (message: string) => {
+    setError(message);
+
+    if (errorTimeoutRef.current) {
+      clearTimeout(errorTimeoutRef.current);
+    }
+
+    errorTimeoutRef.current = window.setTimeout(() => {
+      setError(null);
+    }, 3000);
+  };
+
+  // Load todos from API when the component mounts
+  useEffect(() => {
+    if (!USER_ID) {
+      return;
+    }
+
+    getTodos()
+      .then(setTodos)
+      .catch(() => showError('Unable to load todos'));
+
+    // Cleanup timeout on unmount
+    return () => {
+      if (errorTimeoutRef.current) {
+        clearTimeout(errorTimeoutRef.current);
+      }
+    };
+  }, []);
+
+  // Memoized calculations for derived todo lists
+  const { activeTodos, completedTodos, filteredTodos } = useMemo(() => {
+    const active = todos.filter(t => !t.completed);
+    const completed = todos.filter(t => t.completed);
+    let filtered = todos;
+
+    if (filter === FILTERS.active) {
+      filtered = active;
+    }
+
+    if (filter === FILTERS.completed) {
+      filtered = completed;
+    }
+
+    return {
+      activeTodos: active,
+      completedTodos: completed,
+      filteredTodos: filtered,
+    };
+  }, [todos, filter]);
+
+  // Derived UI states
+  const isAllCompleted = todos.length > 0 && todos.every(t => t.completed);
+  const hasTodos = todos.length > 0 || tempTodo;
+
+  // Add new todo
+  const handleAdd = async (title: string): Promise<boolean> => {
+    const trimmedTitle = title.trim();
+
+    if (!trimmedTitle) {
+      showError('Title should not be empty');
+
+      return false;
+    }
+
+    // Optimistic UI: show temporary todo while request is in progress
+    setTempTodo({
+      id: 0,
+      userId: USER_ID,
+      title: trimmedTitle,
+      completed: false,
+    });
+
+    try {
+      const newTodo = await createTodo({ title: trimmedTitle });
+
+      setTodos(current => [...current, newTodo]);
+
+      return true;
+    } catch {
+      showError('Unable to add a todo');
+
+      return false;
+    } finally {
+      setTempTodo(null);
+    }
+  };
+
+  // Delete a todo
+  const handleDelete = async (id: number) => {
+    setLoadingIds(prev => [...prev, id]);
+
+    try {
+      await deleteTodo(id);
+      setTodos(prev => prev.filter(t => t.id !== id));
+      focusField();
+    } catch {
+      showError('Unable to delete a todo');
+    } finally {
+      setLoadingIds(prev => prev.filter(lid => lid !== id));
+    }
+  };
+
+  // toggle todo
+  const handleToggle = async (todo: Todo) => {
+    setLoadingIds(prev => [...prev, todo.id]);
+
+    try {
+      const updated = await updateTodo(todo.id, {
+        completed: !todo.completed,
+      });
+
+      setTodos(prev => prev.map(t => (t.id === todo.id ? updated : t)));
+    } catch {
+      showError('Unable to update a todo');
+      throw new Error('Update failed');
+    } finally {
+      setLoadingIds(prev => prev.filter(id => id !== todo.id));
+    }
+  };
+
+  const handleToggleAll = async () => {
+    const newStatus = !isAllCompleted;
+    const todosToUpdate = todos.filter(todo => todo.completed !== newStatus);
+
+    try {
+      await Promise.all(todosToUpdate.map(todo => handleToggle(todo)));
+    } catch {}
+  };
+
+  const handleRename = async (
+    todo: Todo,
+    newTitle: string,
+  ): Promise<boolean> => {
+    const trimmed = newTitle.trim();
+
+    if (!trimmed) {
+      await handleDelete(todo.id);
+
+      return true;
+    }
+
+    if (trimmed === todo.title) {
+      return true;
+    }
+
+    setLoadingIds(prev => [...prev, todo.id]);
+
+    try {
+      const updated = await updateTodo(todo.id, {
+        title: trimmed,
+      });
+
+      setTodos(prev => prev.map(t => (t.id === todo.id ? updated : t)));
+
+      return true;
+    } catch {
+      showError('Unable to update a todo');
+
+      return false;
+    } finally {
+      setLoadingIds(prev => prev.filter(id => id !== todo.id));
+    }
+  };
+
+  // Remove all completed todos
+  const handleClearCompleted = async () => {
+    await Promise.allSettled(completedTodos.map(todo => handleDelete(todo.id)));
+    focusField();
+  };
+
+  // If USER_ID is missing, show warning instead of the app
   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 className="todoapp__header">
+          {hasTodos && (
+            <button
+              type="button"
+              className={classNames('todoapp__toggle-all', {
+                active: isAllCompleted,
+              })}
+              data-cy="ToggleAllButton"
+              onClick={handleToggleAll}
+            />
+          )}
+
+          <NewTodoForm
+            onAdd={handleAdd}
+            loading={!!tempTodo}
+            todoFieldRef={todoFieldRef}
+          />
+        </header>
+
+        {hasTodos && (
+          <TodoList
+            todos={filteredTodos}
+            tempTodo={tempTodo}
+            loadingIds={loadingIds}
+            onDelete={handleDelete}
+            onToggle={handleToggle}
+            onRename={handleRename}
+          />
+        )}
+
+        {/* Footer */}
+        {hasTodos && (
+          <footer className="todoapp__footer" data-cy="Footer">
+            <span className="todo-count" data-cy="TodosCounter">
+              {/*eslint-disable-next-line max-len*/}
+              {activeTodos.length} {activeTodos.length === 1 ? 'item' : 'items'}{' '}
+              left
+            </span>
+            <FilterComponent current={filter} onChange={setFilter} />
+            <button
+              type="button"
+              className="todoapp__clear-completed"
+              data-cy="ClearCompletedButton"
+              disabled={completedTodos.length === 0}
+              onClick={handleClearCompleted}
+            >
+              Clear completed
+            </button>
+          </footer>
+        )}
+      </div>
+      <ErrorNotification message={error} onClose={() => setError(null)} />
+    </div>
   );
 };
diff --git a/src/api/todos.ts b/src/api/todos.ts
new file mode 100644
index 0000000000..8a20139297
--- /dev/null
+++ b/src/api/todos.ts
@@ -0,0 +1,27 @@
+import { Todo } from '../types/Todo';
+import { client } from '../utils/fetchClient';
+
+export const USER_ID = 3981;
+
+export const getTodos = () => {
+  return client.get<Todo[]>(`/todos?userId=${USER_ID}`);
+};
+
+// Add more methods here
+// Add new todo
+export const createTodo = ({ title }: { title: string }) => {
+  return client.post<Todo>('/todos', {
+    title,
+    userId: USER_ID,
+    completed: false,
+  });
+};
+
+// Delete todo by id
+export const deleteTodo = (id: number) => {
+  return client.delete(`/todos/${id}`);
+};
+
+export const updateTodo = (id: number, data: Partial<Todo>) => {
+  return client.patch<Todo>(`/todos/${id}`, data);
+};
diff --git a/src/components/ErrorNotification.tsx b/src/components/ErrorNotification.tsx
new file mode 100644
index 0000000000..ad9c5c8585
--- /dev/null
+++ b/src/components/ErrorNotification.tsx
@@ -0,0 +1,30 @@
+import classNames from 'classnames';
+import React from 'react';
+
+interface ErrorNotificationProps {
+  message: string | null;
+  onClose?: () => void;
+}
+
+export const ErrorNotification: React.FC<ErrorNotificationProps> = ({
+  message,
+  onClose,
+}) => {
+  return (
+    <div
+      data-cy="ErrorNotification"
+      className={classNames(
+        'notification is-danger is-light has-text-weight-normal',
+        { hidden: !message },
+      )}
+    >
+      <button
+        data-cy="HideErrorButton"
+        type="button"
+        className="delete"
+        onClick={onClose}
+      />
+      {message}
+    </div>
+  );
+};
diff --git a/src/components/FilterComponent.tsx b/src/components/FilterComponent.tsx
new file mode 100644
index 0000000000..71dd899a04
--- /dev/null
+++ b/src/components/FilterComponent.tsx
@@ -0,0 +1,40 @@
+import React from 'react';
+import { Filter as FilterType, FILTERS } from '../types/Filters';
+import classNames from 'classnames';
+
+interface FilterProps {
+  current: FilterType;
+  onChange: (filter: FilterType) => void;
+}
+
+const capitalize = (value: string) => value[0].toUpperCase() + value.slice(1);
+
+export const FilterComponent: React.FC<FilterProps> = ({
+  current,
+  onChange,
+}) => {
+  return (
+    <nav className="filter" data-cy="Filter">
+      {Object.values(FILTERS).map(filter => {
+        const label = capitalize(filter);
+
+        return (
+          <a
+            key={filter}
+            href={`#/${filter}`}
+            className={classNames('filter__link', {
+              selected: current === filter,
+            })}
+            data-cy={`FilterLink${label}`}
+            onClick={event => {
+              event.preventDefault();
+              onChange(filter);
+            }}
+          >
+            {label}
+          </a>
+        );
+      })}
+    </nav>
+  );
+};
diff --git a/src/components/NewTodoForm.tsx b/src/components/NewTodoForm.tsx
new file mode 100644
index 0000000000..8469caef0b
--- /dev/null
+++ b/src/components/NewTodoForm.tsx
@@ -0,0 +1,44 @@
+import React, { useState } from 'react';
+
+type Props = {
+  onAdd: (title: string) => Promise<boolean>;
+  loading?: boolean;
+  todoFieldRef: React.RefObject<HTMLInputElement>;
+};
+
+export const NewTodoForm: React.FC<Props> = ({
+  onAdd,
+  loading,
+  todoFieldRef,
+}) => {
+  const [title, setTitle] = useState('');
+
+  const handleSubmit = async (event: React.FormEvent) => {
+    event.preventDefault();
+
+    if (loading) {
+      return;
+    }
+
+    const isSuccess = await onAdd(title);
+
+    if (isSuccess) {
+      setTitle(''); // Czyścimy tylko przy sukcesie
+    }
+  };
+
+  return (
+    <form onSubmit={handleSubmit} data-cy="NewTodoForm">
+      <input
+        data-cy="NewTodoField"
+        ref={todoFieldRef}
+        type="text"
+        className="todoapp__new-todo"
+        value={title}
+        onChange={event => setTitle(event.target.value)}
+        placeholder="What needs to be done?"
+        disabled={loading}
+      />
+    </form>
+  );
+};
diff --git a/src/components/TodoItem.tsx b/src/components/TodoItem.tsx
new file mode 100644
index 0000000000..9e08e50ea0
--- /dev/null
+++ b/src/components/TodoItem.tsx
@@ -0,0 +1,134 @@
+import React, { useState } from 'react';
+import { Todo } from '../types/Todo';
+import classNames from 'classnames';
+
+interface Props {
+  todo: Todo;
+  isLoading?: boolean;
+  onDelete: (id: number) => void;
+  onToggle: (todo: Todo) => void;
+  onRename: (todo: Todo, title: string) => Promise<boolean>;
+}
+
+export const TodoItem: React.FC<Props> = ({
+  todo,
+  isLoading = false,
+  onDelete,
+  onToggle,
+  onRename,
+}) => {
+  const [isEditing, setIsEditing] = useState(false);
+  const [title, setTitle] = useState(todo.title);
+
+  const todoClass = classNames('todo', {
+    completed: todo.completed,
+    editing: isEditing,
+    'is-loading': isLoading,
+  });
+
+  const handleFocus = (node: HTMLInputElement | null) => {
+    if (node) {
+      node.focus();
+    }
+  };
+
+  const handleSubmit = async (event?: React.FormEvent) => {
+    event?.preventDefault();
+    const trimmedTitle = title.trim();
+
+    if (!trimmedTitle) {
+      onDelete(todo.id);
+
+      return;
+    }
+
+    if (trimmedTitle === todo.title) {
+      setIsEditing(false);
+
+      return;
+    }
+
+    const success = await onRename(todo, trimmedTitle);
+
+    if (success) {
+      setIsEditing(false);
+    }
+  };
+
+  const handleCancel = () => {
+    setTitle(todo.title);
+    setIsEditing(false);
+  };
+
+  return (
+    <div data-cy="Todo" className={todoClass}>
+      {/* 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={todo.completed}
+          onChange={() => onToggle(todo)}
+        />
+      </label>
+
+      {/* Title or editing input */}
+      {isEditing ? (
+        <form
+          onSubmit={e => {
+            e.preventDefault();
+            handleSubmit();
+          }}
+        >
+          <input
+            ref={handleFocus}
+            data-cy="TodoTitleField"
+            type="text"
+            className="todo__title-field"
+            placeholder="Empty todo will be deleted"
+            value={title}
+            autoFocus
+            onChange={e => setTitle(e.target.value)}
+            onBlur={handleSubmit}
+            onKeyUp={e => {
+              if (e.key === 'Escape') {
+                handleCancel();
+              }
+            }}
+          />
+        </form>
+      ) : (
+        <span
+          data-cy="TodoTitle"
+          className="todo__title"
+          onDoubleClick={() => setIsEditing(true)}
+        >
+          {todo.title}
+        </span>
+      )}
+
+      {/* Remove button (pokazuje się tylko jeśli nie w edycji/loading) */}
+      {!isEditing && !isLoading && (
+        <button
+          type="button"
+          className="todo__remove"
+          data-cy="TodoDelete"
+          onClick={() => onDelete(todo.id)}
+        >
+          ×
+        </button>
+      )}
+
+      {/* overlay will cover the todo while it is being deleted or updated */}
+
+      <div
+        data-cy="TodoLoader"
+        className={classNames('modal overlay', { 'is-active': isLoading })}
+      >
+        <div className="modal-background has-background-white-ter" />
+        <div className="loader" />
+      </div>
+    </div>
+  );
+};
diff --git a/src/components/TodoList.tsx b/src/components/TodoList.tsx
new file mode 100644
index 0000000000..acdcc66a21
--- /dev/null
+++ b/src/components/TodoList.tsx
@@ -0,0 +1,45 @@
+import React from 'react';
+import { Todo } from '../types/Todo';
+import { TodoItem } from './TodoItem';
+
+interface TodoListProps {
+  todos: Todo[];
+  tempTodo: Todo | null;
+  loadingIds: number[];
+  onDelete: (id: number) => void;
+  onToggle: (todo: Todo) => void;
+  onRename: (todo: Todo, title: string) => Promise<boolean>;
+}
+
+export const TodoList: React.FC<TodoListProps> = ({
+  todos,
+  tempTodo,
+  loadingIds,
+  onDelete,
+  onToggle,
+  onRename,
+}) => {
+  return (
+    <section className="todoapp__main" data-cy="TodoList">
+      {todos.map(todo => (
+        <TodoItem
+          key={todo.id}
+          todo={todo}
+          isLoading={loadingIds.includes(todo.id)}
+          onDelete={onDelete}
+          onToggle={onToggle}
+          onRename={onRename}
+        />
+      ))}
+      {tempTodo && (
+        <TodoItem
+          todo={tempTodo}
+          isLoading={true} // tempTodo zawsze ma loader
+          onDelete={() => {}}
+          onToggle={() => {}}
+          onRename={async () => false}
+        />
+      )}
+    </section>
+  );
+};
diff --git a/src/types/Filters.ts b/src/types/Filters.ts
new file mode 100644
index 0000000000..bfbedd26c0
--- /dev/null
+++ b/src/types/Filters.ts
@@ -0,0 +1,7 @@
+export const FILTERS = {
+  all: 'all',
+  active: 'active',
+  completed: 'completed',
+} as const;
+
+export type Filter = (typeof FILTERS)[keyof typeof FILTERS];
diff --git a/src/types/Todo.ts b/src/types/Todo.ts
new file mode 100644
index 0000000000..3f52a5fdde
--- /dev/null
+++ b/src/types/Todo.ts
@@ -0,0 +1,6 @@
+export interface Todo {
+  id: number;
+  userId: number;
+  title: string;
+  completed: boolean;
+}
diff --git a/src/utils/fetchClient.ts b/src/utils/fetchClient.ts
new file mode 100644
index 0000000000..708ac4c17b
--- /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'),
+};