Lukas Hölzer

Lukas Hölzer

Member Since July 4, 2016

37,349

Total Points

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Skills & Experience

  • Spoken Languages

    • German
    • English

430 Achievements

  • Sequence Iterations
  • Iterating and Packing with Dictionaries
  • Introducing Dictionaries
  • Python: Advanced Objects
  • Python: Inheritance
  • Python: Instant Objects
  • Dungeon Game 2
  • Build an Application
  • The Data Analysis Process
  • Getting to Know Your Data
  • Introducing Data Analysis
  • Using Lists
  • Meet Lists
  • All Together Now
  • Functions and Looping
  • Types and Branching
  • Meet Python
  • Testing and Publishing an Alexa Skill
  • Building an Alexa Skill
  • Getting Data From an API With Node
  • Introduction to Node.js
  • Control Flow With Conditional Statements
  • Control Flow With Loops
  • Running Apps on a Device
  • Improving Our User Interface
  • Structs As Data Models
  • View Controllers and Views
  • Getting Started with iOS Development
  • Dictionaries in Swift
  • Introduction to Collections
  • Swift Operators
  • Creating and Modifying Database Tables
  • Swift Types
  • An Introduction to Swift Programming
  • Writing a Classifier
  • Machine Learning Vocabulary
  • Introduction to Machine Learning
  • Vulnerabilities: Configuration, Components, and Logging
  • Vulnerabilities: Authentication, Access, and Sensitive Data
  • Vulnerabilities:  Injection, XSS, CSRF
  • The OWASP Top 10 Explained
  • Maintaining Secure Web Apps
  • Protecting Data and Keeping Attackers Out
  • Why Protect Your Web Apps
  • Introducing the Watson APIs
  • Gotchas and Wins
  • Iteration
  • Creation
  • Dockerize a Web App
  • Managing Images and Containers
  • Building Images Using Dockerfiles
  • Fundamentals of Docker
  • Docker Use Cases
  • Spring Components and Configuring Our App
  • Setting Up Your Local Environment for Spring Development
  • Day 3: Getting Creative
  • Getting Started with Xamarin
  • Day 2: Advanced Selecting
  • Day 1: Joining Tables
  • Orientation: Selecting Data
  • Subqueries
  • Set Operations
  • Joining Table Data with SQL
  • Table Relationships
  • Database Keys
  • Big Data at Netflix
  • Where and How Big Data Is Used
  • What is Big Data
  • Security in Practice
  • Common Attacks and Defenses
  • Hello Internet!
  • What Is WordPress?
  • Writing Your Own Java Annotation
  • Using Java's Built-In Annotations
  • Bells and Whistles
  • Diving into Web Development
  • What to Test
  • How To Test
  • Why Test
  • Using Styles in Layouts
  • The Rest of the Story
  • Finishing the User Interface
  • The Model-View-Presenter Pattern
  • Intents and Multiple Activities
  • Tuning the User Interface
  • User Input in Android
  • Testing and Debugging
  • Improving Our Code
  • Basic Android Programming
  • Creating the Screen Layout
  • Getting Started with Android
  • Delivering the MVP
  • Creating the MVP
  • Harnessing the Power of Objects
  • Meet Objects
  • Security: Solutions
  • Security: Concerns
  • Alexa Skills Kit Overview
  • Lists, Code, Links and Images
  • Understanding Markdown
  • S3 Storage Service
  • AWS and "The Cloud"
  • Python Sets
  • Python Tuples
  • Python Dictionaries
  • Python Slices
  • Python Lists
  • Introducing Entity Framework
  • Finishing Our CRUD Web App
  • Adding Form Validation
  • Improving Our Form
  • Creating a Basic Form
  • Getting Started With Spreadsheets
  • Introducing CRUD Applications
  • Adding a List Page
  • Modeling and Presenting Data
  • Views
  • Controllers
  • Project Setup
  • Introducing Spreadsheets
  • Introduction to Video Games
  • The Unity Editor and Scene Setup
  • Introduction to Video Games
  • The Internet
  • Ruby Class Design
  • Blocks Practice
  • Working With Blocks
  • Ruby Blocks
  • Build a Simple Todo List Program
  • Ruby Booleans
  • Build a Bank Account Class
  • Ruby Variables and Methods
  • Ruby Objects and Classes
  • Build a Simple Contact List
  • Ruby Iteration
  • Ruby Loops
  • Build a Grocery List Program
  • Ruby Hashes
  • Ruby Arrays
  • Ruby Logical Operators
  • Ruby Control Structures
  • Ruby Operators
  • Ruby Methods
  • Ruby Numbers (Ruby Basics)
  • Ruby Strings (Ruby Basics)
  • How Ruby Works
  • Styling and Scaling Data
  • Data Binding with D3
  • Selections with D3
  • Creating an SVG
  • Introduction to SVG
  • Improving the Application Code
  • Editing and Filtering Names
  • Adding and Removing Names
  • Thinking in Components
  • Database Normalization
  • First Steps in React
  • Next Steps
  • Improving Our Tests
  • Behavior Driven Development with Mocha & Chai
  • Introducing Unit Testing
  • Completing and Testing the API
  • Communicating with Mongo Through Mongoose
  • Modeling Data for the API
  • Building API Routes in Express
  • Building a REST Service
  • Express Middleware
  • Sessions and Cookies
  • User Registration and Login
  • What is Authentication?
  • Go Further With Mongo
  • Working With Collections
  • Understanding MongoDB
  • Getting Started with MongoDB
  • Doing More with Express
  • Serving Static Files in Express
  • Using Templates with Express
  • The Request and Response Objects in Express
  • Developing Express Apps Like a Boss
  • Getting Started with Express
  • Improving Our Todo App
  • Services in Angular
  • Using Angular's Built-in Directives
  • Controllers and Scope
  • Getting Started with Angular
  • Improving your Gulp Workflow
  • Compile Sass with Gulp
  • Gulp your JavaScript workflow!
  • Welcome to Gulp.js
  • Updating and Uninstalling Packages with npm
  • Installing Packages with npm
  • What is npm?
  • HTTP Methods and Headers
  • Creating a Basic Template Engine in Node.js
  • Handling Routes in Node.js
  • Creating a Simple Server in Node.js
  • Building a Command Line Application
  • Introduction to Node.js
  • Classes
  • Objects and New Collection Types
  • The Cooler Parts of ES2015
  • ES2015 Basics
  • DOM Traversal
  • DOM Manipulation
  • Events
  • Hello, jQuery!
  • Traversing the DOM
  • Responding to User Interaction
  • Making Changes to the DOM
  • Getting a Handle on the DOM
  • The Browser Environment
  • Query Builder
  • Query Operators
  • Functional!
  • Now You're Querying!
  • Sets and Dictionaries
  • Lists
  • Arrays
  • Data Retreiver
  • Serialized!
  • Data Parser
  • Data Reader
  • Abstraction
  • System.Object
  • Polymorphism
  • Loops and Final Touches
  • Encapsulation with Properties
  • Encapsulation and Arrays
  • Inheritance
  • Methods
  • Object-Oriented Programming
  • Perfect
  • Perform
  • Console I/O
  • Prepare and Plan
  • Combine and Minify Assets
  • Optimize Assets
  • Measuring Performance
  • Planning for Performance
  • Workflows
  • Working With Remote Repositories
  • Merging
  • Branches
  • Getting Started With Git
  • Why Version Control Matters
  • Installing Programs
  • Environment and Redirection
  • Console Processes
  • Console Users and Permission
  • Moving Around in the Console
  • Chrome DevTools Basics
  • Web Apps
  • Websites
  • Introduction
  • Quiz Practice Project
  • Prototypal Inheritance
  • Constructor Functions & Prototypes
  • Introduction to Methods
  • AJAX and APIs
  • jQuery and AJAX
  • Programming AJAX
  • AJAX Concepts
  • Custom Media Players
  • Captioning Video
  • Media Basics
  • Traversing and Manipulating the DOM with JavaScript
  • Selecting Elements and Adding Events with JavaScript
  • JavaScript and the DOM
  • Structuring Tables
  • Table Basics
  • Building Forms with Bootstrap
  • Using Bootstrap Components
  • Responsive Layouts with the Bootstrap Grid
  • Getting to Know Bootstrap 4
  • 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
  • Advanced Selectors
  • Going Further with Attribute Selectors and Pseudo-Classes
  • Selectors - Beyond the Basics
  • JavaScript Objects
  • JavaScript Arrays
  • JavaScript Loops
  • Building a Layout with Flexbox
  • Flexbox Properties
  • Understanding Flexbox
  • Responsive Patterns
  • Media Queries
  • Responsive Theory
  • Positioning Page Content
  • CSS Layout Project
  • Page Layout with the Float Property
  • Controlling Layout with CSS Display Modes
  • Getting Started with CSS Layout
  • JavaScript Functions
  • JavaScript Conditional Statements
  • JavaScript Numbers
  • JavaScript Variables
  • Introducing JavaScript
  • Fundamental Concepts
  • Designing with the Latest Features
  • Basic Layout
  • The Box Model
  • Understanding Values and Units
  • Basic Selectors
  • Getting Started with CSS
  • Debugging HTML and CSS Problems
  • Sharing a Website
  • Responsive Web Design and Testing
  • WordPress User Roles
  • WordPress Plugins
  • WordPress Themes
  • The WordPress Customizer
  • Managing Media in WordPress
  • Managing Content in WordPress
  • How to Install WordPress on Your Computer
  • Getting Started with WordPress
  • Adding Pages to a Website
  • Styling Web Pages and Navigation
  • Customizing Colors and Fonts
  • CSS: Cascading Style Sheets
  • Detail View
  • Creating HTML Content
  • Event Planning
  • Build a Pomodoro App
  • Design a Better App
  • Graphical User Interfaces
  • Advanced Tooling
  • IDE Exploration
  • How it Works
  • Efficiency!
  • Exploring the Java Collections Framework
  • Organizing Data
  • Getting There
  • Delivering the MVP
  • Creating the MVP
  • Harnessing the Power of Objects
  • List View
  • Meet Objects
  • Perfecting the Prototype
  • Using your New Tools
  • Getting Started with Java
  • The Django Admin
  • Date and Time Functions
  • Aggregate and Numeric Functions
  • Working with Text
  • Ordering, Limiting and Paging Results
  • Handling Errors When Manipulating Data
  • Deleting Data from a Database
  • Updating Data in a Database
  • Adding Data to a Database
  • Finding the Data You Want
  • Getting Data from a Database
  • Data, Databases and SQL
  • Securing and Maintaining a MySQL Database
  • SQL Calculating, Aggregating and Other Functions
  • Joining Relational Data Between Tables in SQL
  • Manipulating Schema with SQL
  • Creating Tables and Manipulating Data with SQL
  • Reading Data from Databases with SQL
  • Installing MySQL Server and MySQL Workbench
  • Introduction to Data, Databases and SQL
  • Total Control
  • Basic ORM Usage
  • Same Old ORM
  • Inlines and Media
  • Django Model Forms
  • Django Models
  • Django Forms
  • Building Custom Filters
  • Building Custom Tags
  • Template Tags and Filters
  • Test Time!
  • Final Details
  • Django Templates
  • Model Administration
  • What a View
  • Say Hello to Django
  • The Lambda Lambada
  • Functional Workhorses
  • Functional Rules
  • Covering Your Bases
  • Be Assertive!
  • What Is Testing?
  • API Protection
  • Resourceful Blueprints
  • Getting the REST You Need
  • Tacocat Challenge
  • How to Win Friends
  • Getting Started with Data Science
  • Python Regular Expressions
  • Timezones
  • Math Quiz App
  • Dates and Times
  • Choosing Options
  • Organizing Forms
  • Form Basics
  • HTML First
  • Beginning HTML and CSS
  • Buggy Logs
  • Cleaner Code
  • Broadcasting
  • Takin' Names
  • Making Strong Users
  • Gettin' CRUD-y With It
  • Our Diary App
  • Meet Peewee
  • GET and POST Requests in a Browser
  • Introduction to HTTP
  • Character Builder
  • Flask Templates
  • Welcome to Flask
  • Hack-n-Slash
  • Python Inheritance
  • Python Objects
  • Dungeon Game
  • Tuples
  • Dictionaries
  • Slices
  • Lists Redux
  • Letter Game App
  • Number Game App
  • Shopping List App
  • Logic in Python
  • Python Data Types
  • Python For Beginners
  • Newbie