Marcin Robert Kaźmierczak

Marcin Robert Kaźmierczak

Warsaw, Skierniewice, Poland

33,570

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Skills & Experience

  • Job Title

    Senior Backend Developer

  • Spoken Languages

    • Polish
    • English
    • German

425 Achievements

  • JavaScript Functions
  • Data Types and Variables
  • JavaScript Frameworks, Libraries, and Developer Roles
  • JavaScript Outside of the Browser
  • Finishing the Game
  • Introducing JavaScript
  • What is Authentication
  • PHP on the Web
  • Daily Exercise Program
  • Unit Converter
  • First Steps in React
  • Getting to Know PHP
  • Why Object-Oriented Programming?
  • Building Forms with Bootstrap
  • Using Bootstrap Components
  • Responsive Layouts with the Bootstrap Grid
  • Getting to Know Bootstrap 4
  • PHPDB Stage 2: Querying the Database with PHP
  • PHPDB Stage 1: Databases and PHP
  • Meet Objects
  • Relating Models
  • Laravel Controllers
  • Laravel Project Setup
  • Laravel Getting Started
  • Building WordPress Template Tags, Widgets, and Shortcodes
  • Go Further With Mongo
  • Working With Collections
  • Understanding MongoDB
  • Getting Started with MongoDB
  • Date and Time Functions
  • Aggregate and Numeric Functions
  • Working with Text
  • Ordering, Limiting and Paging Results
  • Perfecting the Prototype
  • Using your New Tools
  • Getting Started with Java
  • Testing and Debugging
  • Improving Our Code
  • Basic Android Programming
  • Creating the Screen Layout
  • Getting Started with Android
  • WordPress Admin Settings
  • Get Involved in Open Source
  •  Create a Web Presence on GitHub
  •  Working on a Team
  • Working By Yourself
  • Hello, GitHub!
  • PHP Email Form Errors
  • PHP Email Forms
  • Adding a New Web Page
  • Make It Beautiful with CSS
  • HTML: The Structural Foundation of Web Pages and Applications
  • Getting Familiar with HTML and CSS
  • PHP Inventory
  • PHP Includes
  • Handling Errors When Manipulating Data
  • Deleting Data from a Database
  • Updating Data in a Database
  • Adding Data to a Database
  • Getting Started with Angular
  • Finding the Data You Want
  • Getting Data from a Database
  • Data, Databases and SQL
  • Positioning Page Content
  • CSS Layout Project
  • Page Layout with the Float Property
  • Customizing the User Experience in WordPress
  • Default User Roles in WordPress
  • An Overview of User Roles and Fields
  • Controlling Layout with CSS Display Modes
  • Getting Started with CSS Layout
  • Creating the Initial Screen Layout
  • Getting Started with Android
  • JavaScript Loops
  • The Internet
  • Scrum Artifacts
  • Scrum Events
  • Introducing Scrum
  • What is Agile?
  • Getting Started with BuddyPress
  • Launching and Supporting a WordPress Plugin
  • The Settings API in Different Places
  • Taking WordPress Settings Further
  • Getting Started with Theme Options Settings
  • WordPress Settings API Overview
  • SEO Plugins for WordPress
  • Enhancing the SEO of a WordPress Theme
  • Content Comes First
  • More Advanced PHP for WordPress
  • PHP Basics for WordPress
  • Introduction to PHP for WordPress
  • Hosting with GitHub Pages
  • Building and Customizing the Blog
  • Getting Started with Jekyll
  • Contact Forms & Mailers
  • Slim and Templates
  • Using a jQuery Carousel
  • Add a Sticky Navigation Bar
  • Introducing jQuery Plugins
  • Installing a Ruby Development Environment
  • Ruby Methods
  • Ruby Numbers (Ruby Basics)
  • Connecting WordPress Plugins with 3rd Party APIs
  • Building a WordPress Plugin Settings Page
  • How WordPress Plugins Work
  • Hooking Into WordPress Plugins
  • Action Functions in WordPress
  • Filter Functions in WordPress
  • An Overview of Hooks in WordPress
  • Custom WordPress Customizer Settings
  • Native WordPress Customizer Options
  • Overview of the WordPress Customizer
  • Custom Dashboard Widgets
  • Controlling Admin Navigation
  • Dependency Management
  • Customizing the Login Screen
  • What is the MailChimp API
  • Admin Color Schemes
  • Add Bootstrap Components to WordPress Theme
  • Create Bootstrap Styled Theme Templates
  • Setup a Bootstrap Theme
  • Improving Usability
  • Mobile Usability
  • Website Usability
  • What is Usability?
  • Moving from WordPress.com to Self-Hosted WordPress.org
  • Running an Ecommerce Site Long Term
  • Extending WooCommerce
  • Managing Orders in WooCommerce
  • Managing Products in WooCommerce
  • Setting Up WooCommerce
  • Introduction to Ecommerce with WordPress
  • Final Project: Create a Typographic Site
  • Laying Out Type for the Web
  • Basic Web Typography
  • How to Choose and Use Webfonts
  • Introduction to Typography
  • Art Direction with the Picture Element
  • Image Delivery with Srcset and Sizes
  • WWW
  • A Template Hierarchy Review
  • Media Templates in WordPress
  • Custom Post Type Templates
  • Archive Templates in WordPress
  • Page and Post Templates in WordPress
  • Homepage Templates in WordPress
  • Core WordPress Theme Files
  • How WordPress Templates Work
  • The Production Server
  • The Staging Server
  • The Local Development Environment
  • Database Security
  • Queries & Results
  • Getting Started with PDO
  • The Logo Sprint
  • Logo Design 101
  • Structuring Tables
  • Table Basics
  • Custom Media Players
  • Captioning Video
  • Media Basics
  • MASH JavaScript
  • MASH CSS
  • MASH HTML
  • Working with Media Queries
  • Ruby Strings (Ruby Basics)
  • Computer Languages
  • Computer Basics
  • Treehouse Club - JavaScript
  • CSS Animation Basics
  • Welcome to the Treehouse Club
  • Understanding CSS Transitions and Transforms
  • How Ruby Works
  • Understanding Flexbox and Multi-Column Layout
  • Owning a WordPress Site Long Term
  • WordPress Community Management
  • Working with Media in WordPress
  • Adding and Editing Content
  • Getting a WordPress Site
  • Combine and Minify Assets
  • Optimize Assets
  • Measuring Performance
  • Planning for Performance
  • PHP Internal Functions
  • PHP Returns & Closures
  • PHP Functions Basics
  • Responsive Patterns
  • Media Queries
  • Responsive Theory
  • Error Handling
  • Creating Distributable OOP Packages
  • Autoloading and Composer
  • Databases and International Concerns
  • Starting Right with PHP Best Practices
  • Test Doubles
  • Acceptance Tests
  • Organizing your Tests
  • Creating Your Tests
  • Tools for Testers
  • How To Test Our Code
  • Advanced Selectors
  • Going Further with Attribute Selectors and Pseudo-Classes
  • Selectors - Beyond the Basics
  • Treehouse Club - CSS
  • PHP Loops
  • PHP Conditionals
  • PHP Datatypes
  • PHP Data & Structure
  • PHP Getting Started
  • PHP Inheritance & Interfaces
  • Customizing Google Maps
  • Form Validation and Manipulation
  • Designing with the Latest Features
  • Fundamental Concepts
  • Basic Layout
  • Understanding Values and Units
  • The Box Model
  • Basic Selectors
  • Getting Started with CSS
  • Creating an SVG
  • Introduction to SVG
  • Introduction to Node.js
  • Traversing and Manipulating the DOM with JavaScript
  • Selecting Elements and Adding Events with JavaScript
  • JavaScript and the DOM
  • JavaScript Functions
  • JavaScript Conditional Statements
  • Finishing Your WordPress Theme
  • JavaScript Numbers
  • JavaScript Variables
  • Introducing JavaScript
  • Custom Homepage Templates in WordPress
  • Adding a Blog to a WordPress Theme
  • Custom Post Type Templates
  • Building Out WordPress Navigation
  • Building Page Templates in WordPress
  • The WordPress Loop
  • WordPress Header and Footer Templates
  • Working with CSS and JS in WordPress Themes
  • Getting Started with WordPress
  • Starting a WordPress Theme
  • Launching a WordPress Site
  • WordPress and Forms
  • Extending WordPress Template Functionality
  • Converting Static HTML into WordPress Templates
  • PHP Properties & Methods
  • Preparing to Code WordPress Templates
  • WordPress Theme Functions
  • WordPress Theme Templates
  • Content Strategy with WordPress
  • PHP Objects and Classes
  • Introduction to jQuery
  • Why Start a Business?
  • What's New in Foundation 5
  • Build a Website With Foundation
  • Prototyping With Foundation
  • Going Mobile
  • Designing Email with CSS
  • Coding HTML Email
  • HTML Email Basics
  • Local WordPress Development
  • WordPress Plugin Best Practices
  • Widgets and Custom Menus
  • Custom Post Types and Fields
  • Customizing WordPress Themes
  • WordPress Themes
  • Installing Wordpress
  • Build a Website With Bootstrap
  • Choosing Options
  • Organizing Forms
  • Form Basics
  • AJAX and APIs
  • jQuery and AJAX
  • Programming AJAX
  • Paginating a List: Model and View
  • Paginating a List: Controller
  • Adding Search: Model
  • WordPress Admin Settings
  • WordPress User Roles
  • Finding Good WordPress Plugins and Themes
  • Managing Comments on a WordPress Blog
  • Working with Media in WordPress Blogs
  • Posts and Pages in WordPress
  • Blogging with WordPress Overview
  • Adding Search: Controller & View
  • Refactoring the Codebase
  • Prototyping With Bootstrap
  • Introduction to Front-End Frameworks
  • Website Basics
  • DNS Basics
  • Graphic Basics
  • Cleaning URLs with Rewrite Rules
  • Cleaning URLs with Subfolders
  • Integrating Validation Errors
  • Limiting Results in Queries
  • Using Relationship Tables
  • Filtering Input for Queries
  • Querying the Database
  • Connecting to MySQL
  • Finalizing the Project
  • Case Studies and Examples
  • The Brand Identity Design Process
  • Introduction to Brand Identity
  • Creating Tables and Manipulating Data with SQL
  • Securing and Maintaining a MySQL Database
  • SQL Calculating, Aggregating and Other Functions
  • Joining Relational Data Between Tables in SQL
  • Manipulating Schema with SQL
  • Reading Data from Databases with SQL
  • Installing MySQL Server and MySQL Workbench
  • Introduction to Data, Databases and SQL
  • AJAX Concepts
  • Creating a Simple Drawing Application
  • Creating a Password Confirmation Form
  • Creating a Mobile Drop Down Menu
  • Creating a Simple Lightbox
  • Creating a Spoiler Revealer
  • Introduction to jQuery
  • JavaScript Objects
  • JavaScript Functions
  • JavaScript Arrays
  • JavaScript Numbers
  • JavaScript Strings
  • Workflows
  • Working With Remote Repositories
  • Merging
  • Branches
  • Getting Started With Git
  • Chrome DevTools Basics
  • Web Apps
  • Websites
  • Introduction
  • Environment and Redirection
  • Installing Programs
  • Console Processes
  • Console Users and Permission
  • Moving Around in the Console
  • The WordPress Codex
  • Moving Forward with UX
  • Tools UXers Use
  • How UXers Think
  • What Do User Experience Designers Do?
  • What is User Experience (UX)?
  • Why Version Control Matters
  • Advanced Sass Concepts
  • Speeding up Workflow With Sass
  • Variables, Mixins, and Extending Selectors
  • Getting Started with Sass
  • Better SEO Through Tools
  • Better SEO Through Code
  • Better SEO Through Content
  • Introduction to SEO
  • Creating Home Page Assets
  • Applying Effects
  • How to Draw in Illustrator
  •  Adding Color and Type
  • Creating an Icon
  • Introduction to Illustrator
  • Workflow Basics
  • Slices & Save for Web
  • Vector Shapes
  • Type Tools
  • Masks Basics
  • Layer Basics
  • Workspace Basics
  • Design Foundations Final
  • Becoming a Problem Solver
  • Understanding Aesthetics
  • Introduction to Design
  • Simple PHP Application: Wrapping Up The Project
  • Working with PHP Functions
  • Integrating With Paypal
  • Listing Inventory Items
  • Adding a Contact Form
  • Introduction Variables
  • Color Theory
  • Principles
  • Elements
  • Media Queries
  • CSS Animations
  • Transitions and Transforms
  • Flexbox and Multi-Column Layout
  • Gradients
  • Web Typography
  • Backgrounds and Borders
  • Debugging HTML and CSS Problems
  • Sharing a Website
  • Responsive Web Design and Testing
  • Adding Pages to a Website
  • Styling Web Pages and Navigation
  • Customizing Colors and Fonts
  • CSS: Cascading Style Sheets
  • Creating HTML Content
  • HTML First
  • Beginning HTML and CSS
  • CSS Box Model
  • Text, Fonts, and Lists
  • Values and Units
  • Creating the Menu and Footer
  • Getting Started with PHP
  • Advanced Selectors
  • Selectors
  • Grid Layout
  • Flexbox Layout
  • Positioning Schemes
  • Float Layout
  • Display Modes
  • Getting Started with CSS
  • Forms
  • Tables
  • Objects
  • Links
  • Lists
  • Text
  • Introduction
  • Functions
  • Objects and Arrays
  • Control Structures
  • Basics
  • Launching the Website
  • Styling Content
  • Creating a Website Structure
  • Text Editors and HTML
  • Website Basics
  • Newbie