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Marek Ostrowski

Rzeszów, Poland

Open to Work

16,122

Total Points

•
3,700

JavaScript

3700 pts
Achievements

0 pts
Forum
•
3,525

Python

3525 pts
Achievements

0 pts
Forum
•
2,865

CSS

2865 pts
Achievements

0 pts
Forum
•
1,447

Databases

1447 pts
Achievements

0 pts
Forum
•
1,367

HTML

1367 pts
Achievements

0 pts
Forum
•
1,333

Development Tools

1333 pts
Achievements

0 pts
Forum
•
199

Security

199 pts
Achievements

0 pts
Forum
•
172

Digital Literacy

172 pts
Achievements

0 pts
Forum
•
140

Java

140 pts
Achievements

0 pts
Forum
•
135

Data Analysis

135 pts
Achievements

0 pts
Forum
•
52

PHP

52 pts
Achievements

0 pts
Forum
•
5

APIs

5 pts
Achievements

0 pts
Forum
•
3

AI

3 pts
Achievements

0 pts
Forum
•
1

Quality Assurance

1 pts
Achievements

0 pts
Forum

Points are earned whenever you take an important action on Treehouse.
Learn more about when and how points are earned.

Skills & Experience

Company

F.H. BOZ S.A.
Spoken Languages
- English
- Polish

186 Achievements

Achievement
Day 3: Getting Creative

SQL Reporting by Example

Achieved
Apr 7, 2024
Achievement
Day 2: Advanced Selecting

SQL Reporting by Example

Achieved
Mar 27, 2024
Achievement
Day 1: Joining Tables

SQL Reporting by Example

Achieved
Mar 26, 2024
Achievement
Orientation: Selecting Data

SQL Reporting by Example

Achieved
Mar 26, 2024
Achievement
Subqueries

Querying Relational Databases

Achieved
Mar 21, 2024
Achievement
Set Operations

Querying Relational Databases

Achieved
Mar 21, 2024
Achievement
Joining Table Data with SQL

Querying Relational Databases

Achieved
Mar 19, 2024
Achievement
Table Relationships

Querying Relational Databases

Achieved
Mar 17, 2024
Achievement
Database Keys

Querying Relational Databases

Achieved
Mar 16, 2024
Achievement
Database Normalization

Querying Relational Databases

Achieved
Mar 16, 2024
Achievement
Date and Time Functions

Reporting with SQL

Achieved
Mar 12, 2024
Achievement
Aggregate and Numeric Functions

Reporting with SQL

Achieved
Mar 11, 2024
Achievement
Working with Text

Reporting with SQL

Achieved
Mar 10, 2024
Achievement
Ordering, Limiting and Paging Results

Reporting with SQL

Achieved
Mar 10, 2024
Achievement
Handling Errors When Manipulating Data

Modifying Data with SQL

Achieved
Mar 7, 2024
Achievement
Deleting Data from a Database

Modifying Data with SQL

Achieved
Mar 7, 2024
Achievement
Updating Data in a Database

Modifying Data with SQL

Achieved
Mar 7, 2024
Achievement
Adding Data to a Database

Modifying Data with SQL

Achieved
Mar 7, 2024
Achievement
Using your New Tools

Java Basics

Achieved
Apr 9, 2023
Achievement
Getting Started with Java

Java Basics

Achieved
Apr 9, 2023
Achievement
Introduction to SQLAlchemy

SQLAlchemy Basics

Achieved
Mar 15, 2023
Achievement
Python Regular Expressions

Regular Expressions in Python

Achieved
Feb 23, 2023
Achievement
Data Cleaning

Preparing Data for Analysis

Achieved
Jan 9, 2023
Achievement
Understanding Cleaning Data

Preparing Data for Analysis

Achieved
Jan 6, 2023
Achievement
Exploring pandas

Introduction to pandas

Achieved
Jan 6, 2023
Achievement
Meet pandas

Introduction to pandas

Achieved
Jan 2, 2023
Achievement
Array Programming

Introduction to NumPy

Achieved
Dec 30, 2022
Achievement
Array Organization

Introduction to NumPy

Achieved
Dec 29, 2022
Achievement
Meet NumPy

Introduction to NumPy

Achieved
Dec 28, 2022
Achievement
Dice Roller

Object-Oriented Python

Achieved
Dec 23, 2022
Achievement
Python: Advanced Objects

Object-Oriented Python

Achieved
Dec 22, 2022
Achievement
Python: Inheritance

Object-Oriented Python

Achieved
Dec 17, 2022
Achievement
Python: Instant Objects

Object-Oriented Python

Achieved
Dec 16, 2022
Achievement
Communicating with a RESTful API

Using the GitHub API with PHP

Achieved
Dec 6, 2022
Achievement
GET and POST Requests in a Browser

HTTP Basics

Achieved
Nov 25, 2022
Achievement
Introduction to HTTP

HTTP Basics

Achieved
Nov 22, 2022
Achievement
Character Builder

Flask Basics

Achieved
Nov 21, 2022
Achievement
Flask Templates

Flask Basics

Achieved
Nov 16, 2022
Achievement
Welcome to Flask

Flask Basics

Achieved
Nov 3, 2022
Achievement
Buggy Logs

Write Better Python

Achieved
Nov 3, 2022
Achievement
Cleaner Code

Write Better Python

Achieved
Oct 30, 2022
Achievement
Timezones

Dates and Times in Python (2014)

Achieved
Oct 30, 2022
Achievement
Math Quiz App

Dates and Times in Python (2014)

Achieved
Oct 26, 2022
Achievement
Dates and Times

Dates and Times in Python (2014)

Achieved
Oct 23, 2022
Achievement
Creating a Memory Game

Basic Object-Oriented Python

Achieved
Oct 15, 2022
Achievement
Emulating Built-ins

Basic Object-Oriented Python

Achieved
Oct 9, 2022
Achievement
Welcome to OOP

Basic Object-Oriented Python

Achieved
Oct 1, 2022
Achievement
Security in Practice

Security Literacy

Achieved
May 30, 2022
Achievement
Common Attacks and Defenses

Security Literacy

Achieved
May 29, 2022
Achievement
Hello Internet!

Security Literacy

Achieved
May 29, 2022
Achievement
Rendering the Game

Object-Oriented JavaScript: Challenge

Achieved
May 22, 2022
Achievement
Common Commands

Introduction to the Terminal

Achieved
May 22, 2022
Achievement
Directories and Files

Introduction to the Terminal

Achieved
Apr 10, 2022
Achievement
The Command Shell

Introduction to the Terminal

Achieved
Apr 9, 2022
Achievement
Building Constructor Methods and Generating Objects

Object-Oriented JavaScript: Challenge

Achieved
Feb 6, 2022
Achievement
Checking Out and Returning a Book

Practice Object Interaction

Achieved
Jan 30, 2022
Achievement
Starting with Some Methods

Practice Object Interaction

Achieved
Jan 23, 2022
Achievement
The Rough Plan

Practice Object Interaction

Achieved
Jan 23, 2022
Achievement
Getting the REST You Need 2

Introduction to REST APIs

Achieved
Jan 22, 2022
Achievement
Practicing Getters and Setters

Practice Getters and Setters in JavaScript

Achieved
Jan 16, 2022
Achievement
Practicing Classes

Practice Classes in JavaScript

Achieved
Jan 1, 2022
Achievement
Introducing 'Four in a Row'

Object-Oriented JavaScript: Challenge

Achieved
Dec 28, 2021
Achievement
JavaScript Tools and Workflows

The Landscape of JavaScript

Achieved
Dec 28, 2021
Achievement
JavaScript is Everywhere

The Landscape of JavaScript

Achieved
Dec 26, 2021
Achievement
Chrome DevTools Basics

Website Optimization

Achieved
Dec 26, 2021
Achievement
Traversing the DOM

Interacting with the DOM

Achieved
Nov 13, 2021
Achievement
Making Changes to the DOM

JavaScript and the DOM

Achieved
Nov 7, 2021
Achievement
Getting a Handle on the DOM

JavaScript and the DOM

Achieved
Nov 7, 2021
Achievement
The Browser Environment

JavaScript and the DOM

Achieved
Nov 6, 2021
Achievement
Exploring Async/Await

Asynchronous Programming with JavaScript

Achieved
Oct 30, 2021
Achievement
Understanding Promises

Asynchronous Programming with JavaScript

Achieved
Oct 24, 2021
Achievement
Asynchronous JavaScript with Callbacks

Asynchronous Programming with JavaScript

Achieved
Oct 3, 2021
Achievement
Finding the Data You Want

SQL Basics

Achieved
Sep 26, 2021
Achievement
Getting Data from a Database

SQL Basics

Achieved
Sep 19, 2021
Achievement
Data, Databases and SQL

SQL Basics

Achieved
Sep 18, 2021
Achievement
What is Asynchronous Programming?

Asynchronous Programming with JavaScript

Achieved
Jun 2, 2021
Achievement
Getters and Setters

Object-Oriented JavaScript

Achieved
May 30, 2021
Achievement
Working with Classes in JavaScript

Object-Oriented JavaScript

Achieved
May 30, 2021
Achievement
Object Basics

Object-Oriented JavaScript

Achieved
May 29, 2021
Achievement
Introduction to Object-Oriented JavaScript

Object-Oriented JavaScript

Achieved
May 29, 2021
Achievement
Programming AJAX

AJAX Basics

Achieved
May 29, 2021
Achievement
AJAX Concepts

AJAX Basics

Achieved
May 27, 2021
Achievement
Captioning Video

HTML Video and Audio

Achieved
May 23, 2021
Achievement
Media Basics

HTML Video and Audio

Achieved
May 23, 2021
Achievement
Structuring Tables

HTML Tables

Achieved
May 22, 2021
Achievement
Table Basics

HTML Tables

Achieved
May 21, 2021
Achievement
Combine and Minify Assets

Introduction to Front End Performance Optimization

Achieved
May 16, 2021
Achievement
Optimize Assets

Introduction to Front End Performance Optimization

Achieved
May 15, 2021
Achievement
Measuring Performance

Introduction to Front End Performance Optimization

Achieved
May 15, 2021
Achievement
Planning for Performance

Introduction to Front End Performance Optimization

Achieved
May 9, 2021
Achievement
Going Further with Grid Layout

CSS Grid Layout

Achieved
May 9, 2021
Achievement
Flexible Sized Grids

CSS Grid Layout

Achieved
May 3, 2021
Achievement
Introducing Grid Layout

CSS Grid Layout

Achieved
May 3, 2021
Achievement
Mobile-First CSS Layout

Mobile-First CSS Layout

Achieved
May 2, 2021
Achievement
GitHub and Other Remote Repositories

Introduction to Git

Achieved
Apr 26, 2021
Achievement
Managing Committed Files

Introduction to Git

Achieved
Apr 26, 2021
Achievement
First Commits

Introduction to Git

Achieved
Apr 25, 2021
Achievement
Finishing Touches

Enhancing Design with CSS

Achieved
Apr 20, 2021
Achievement
Styling Images

Enhancing Design with CSS

Achieved
Apr 19, 2021
Achievement
Styling Boxes

Enhancing Design with CSS

Achieved
Apr 19, 2021
Achievement
Styling Text

Enhancing Design with CSS

Achieved
Apr 19, 2021
Achievement
CSS Media Queries

CSS Layout

Achieved
Apr 14, 2021
Achievement
CSS Layout Techniques

CSS Layout

Achieved
Mar 27, 2021
Achievement
Box Model Concepts

CSS Layout

Achieved
Mar 22, 2021
Achievement
Fundamental Concepts

CSS Basics

Achieved
Mar 22, 2021
Achievement
Understanding Values and Units

CSS Basics

Achieved
Mar 22, 2021
Achievement
Basic Selectors

CSS Basics

Achieved
Jan 17, 2021
Achievement
Getting Started with CSS

CSS Basics

Achieved
Jan 15, 2021
Achievement
The CSS Box Model

CSS Layout

Achieved
Jan 13, 2021
Achievement
Building Forms With Bootstrap

Bootstrap Basics

Achieved
Jan 13, 2021
Achievement
Using Bootstrap Components

Bootstrap Basics

Achieved
Jan 3, 2021
Achievement
Responsive Layouts With the Bootstrap Grid

Bootstrap Basics

Achieved
Dec 20, 2020
Achievement
Getting to Know Bootstrap 4

Bootstrap Basics

Achieved
Dec 19, 2020
Achievement
Traversing the DOM

JavaScript and the DOM (Retiring)

Achieved
Dec 13, 2020
Achievement
Responding to User Interaction

Interacting with the DOM

Achieved
Dec 6, 2020
Achievement
Making Changes to the DOM

JavaScript and the DOM (Retiring)

Achieved
Nov 30, 2020
Achievement
Getting a Handle on the DOM

JavaScript and the DOM (Retiring)

Achieved
Nov 22, 2020
Achievement
The Browser Environment

JavaScript and the DOM (Retiring)

Achieved
Nov 19, 2020
Achievement
Advanced Selectors

CSS Selectors

Achieved
Nov 19, 2020
Achievement
Going Further with Attribute Selectors and Pseudo-Classes

CSS Selectors

Achieved
Nov 14, 2020
Achievement
Selectors - Beyond the Basics

CSS Selectors

Achieved
Nov 11, 2020
Achievement
Loop Through Objects

JavaScript Objects

Achieved
Nov 7, 2020
Achievement
Object Basics

JavaScript Objects

Achieved
Nov 2, 2020
Achievement
Multidimensional Arrays

JavaScript Arrays

Achieved
Nov 1, 2020
Achievement
Loop Through Arrays

JavaScript Arrays

Achieved
Oct 31, 2020
Achievement
Store Multiple Values in an Array

JavaScript Arrays

Achieved
Oct 31, 2020
Achievement
Working with 'for' Loops

JavaScript Loops

Achieved
Oct 30, 2020
Achievement
Simplify Repetitive Tasks with Loops

JavaScript Loops

Achieved
Oct 28, 2020
Achievement
Build an Accessible Form

Accessibility For Web Developers

Achieved
Oct 28, 2020
Achievement
Introduction To Accessibility

Accessibility For Web Developers

Achieved
Oct 24, 2020
Achievement
Arrow Functions

JavaScript Functions

Achieved
Oct 23, 2020
Achievement
Pass Information Into Functions

JavaScript Functions

Achieved
Oct 20, 2020
Achievement
Create Reusable Code with Functions

JavaScript Functions

Achieved
Oct 20, 2020
Achievement
The Math Object

JavaScript Numbers

Achieved
Oct 19, 2020
Achievement
Working with Numbers

JavaScript Numbers

Achieved
Oct 18, 2020
Achievement
Making Decisions in Your Code with Conditional Statements

JavaScript Basics

Achieved
Oct 18, 2020
Achievement
Working With Strings

JavaScript Basics

Achieved
Oct 12, 2020
Achievement
Storing and Tracking Information with Variables

JavaScript Basics

Achieved
Oct 8, 2020
Achievement
Hello, JavaScript!

JavaScript Basics

Achieved
Oct 8, 2020
Achievement
Choosing Options

HTML Forms

Achieved
Oct 7, 2020
Achievement
Organizing Forms

HTML Forms

Achieved
Sep 30, 2020
Achievement
Form Basics

HTML Forms

Achieved
Sep 30, 2020
Achievement
Building a Layout with Flexbox

CSS Flexbox Layout

Achieved
Sep 27, 2020
Achievement
Flexbox Properties

CSS Flexbox Layout

Achieved
Sep 27, 2020
Achievement
Understanding Flexbox

CSS Flexbox Layout

Achieved
Sep 24, 2020
Achievement
Responsive Patterns

Responsive Layouts

Achieved
Sep 23, 2020
Achievement
Media Queries

Responsive Layouts

Achieved
Sep 23, 2020
Achievement
Responsive Theory

Responsive Layouts

Achieved
Sep 22, 2020
Achievement
Positioning Page Content

CSS Layout Basics

Achieved
Sep 22, 2020
Achievement
CSS Layout Project

CSS Layout Basics

Achieved
Sep 13, 2020
Achievement
Page Layout with the Float Property

CSS Layout Basics

Achieved
Sep 6, 2020
Achievement
Controlling Layout with CSS Display Modes

CSS Layout Basics

Achieved
Sep 3, 2020
Achievement
Getting Started with CSS Layout

CSS Layout Basics

Achieved
Sep 2, 2020
Achievement
Fundamental Concepts

CSS Basics (2014)

Achieved
Aug 29, 2020
Achievement
Designing with the Latest Features

CSS Basics (2014)

Achieved
Aug 29, 2020
Achievement
The Internet

How the Internet Works

Achieved
Jul 6, 2020
Achievement
Basic Layout

CSS Basics (2014)

Achieved
Jan 5, 2020
Achievement
The Box Model

CSS Basics (2014)

Achieved
Jan 4, 2020
Achievement
Understanding Values and Units

CSS Basics (2014)

Achieved
Dec 15, 2019
Achievement
Basic Selectors

CSS Basics (2014)

Achieved
Dec 15, 2019
Achievement
Getting Started with CSS

CSS Basics (2014)

Achieved
Dec 14, 2019
Achievement
Going Further with HTML

HTML Basics

Achieved
Dec 11, 2019
Achievement
Images, Text and Links

HTML Basics

Achieved
Dec 10, 2019
Achievement
Structuring Your Content

HTML Basics

Achieved
Dec 10, 2019
Achievement
Getting Started With HTML

HTML Basics

Achieved
Dec 8, 2019
Achievement
Adding a New Web Page

Introduction to HTML and CSS (2016)

Achieved
Dec 8, 2019
Achievement
Make It Beautiful with CSS

Introduction to HTML and CSS (2016)

Achieved
Dec 8, 2019
Achievement
HTML: The Structural Foundation of Web Pages and Applications

Introduction to HTML and CSS (2016)

Achieved
Dec 8, 2019
Achievement
Getting Familiar with HTML and CSS

Introduction to HTML and CSS (2016)

Achieved
Dec 7, 2019
Achievement
Practice Functions

Practice Creating and Using Functions in Python

Achieved
Dec 7, 2019
Achievement
Iterating and Packing with Dictionaries

Introducing Dictionaries

Achieved
Dec 6, 2019
Achievement
Introducing Dictionaries

Introducing Dictionaries

Achieved
Dec 6, 2019
Achievement
Sequence Operations

Python Sequences

Achieved
Dec 5, 2019
Achievement
Sequence Iterations

Python Sequences

Achieved
Nov 30, 2019
Achievement
Packing and Unpacking

Functions, Packing, and Unpacking

Achieved
Nov 30, 2019
Achievement
Getting Info In and Out of Functions

Functions, Packing, and Unpacking

Achieved
Nov 30, 2019
Achievement
Introduction to Functions

Functions, Packing, and Unpacking

Achieved
Nov 28, 2019
Achievement
Getting to Know Tuples

Introducing Tuples

Achieved
Nov 28, 2019
Achievement
Build an Application

Introducing Lists

Achieved
Nov 28, 2019
Achievement
Using Lists

Introducing Lists

Achieved
Nov 26, 2019
Achievement
Meet Lists

Introducing Lists

Achieved
Nov 24, 2019
Achievement
All Together Now

Python Basics

Achieved
Nov 23, 2019
Achievement
Functions and Looping

Python Basics

Achieved
Nov 22, 2019
Achievement
Types and Branching

Python Basics

Achieved
Nov 21, 2019
Achievement
Meet Python

Python Basics

Achieved
Nov 20, 2019
Achievement
Newbie

Achieved
Nov 19, 2019