Zimri Leijen

Zimri Leijen

Lelystad, Netherlands

11,676

Total Points

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Skills & Experience

  • Spoken Languages

    • Dutch
    • English

155 Achievements

  •  Learning activity: Interviewing
  • Learning activity: Field Observation
  • Learning activity: Experience Sampling
  • Finding participants for your learning activity
  • Solving an Important Problem
  • Next Steps
  • Financing Our Company
  • Selling Your Product
  • Marketing Your Product
  • Product Market Fit
  • Discovery
  • Business Plan for Freelance Business
  • Business Plan Basics
  • Moving Beyond the Blog
  • Finding Business
  • Creating Content
  • Introduction to Blogging
  • Video Marketing
  • Email Marketing
  • Search Engine Optimization
  • Usability Testing
  • Usability Basics
  • Social Media
  • Reusable GraphQL
  • Making Changes with Mutations
  • Fetching Data with Queries
  • Getting Started with GraphQL
  • Completing and Testing the API
  • Communicating with Mongo Through Mongoose
  • Modeling Data for the API
  • Building API Routes in Express
  • Building a REST Service
  • Vulnerabilities: Configuration, Components, and Logging
  • Vulnerabilities: Authentication, Access, and Sensitive Data
  • Vulnerabilities:  Injection, XSS, CSRF
  • The OWASP Top 10 Explained
  • Introducing the Authentication Project
  • React Router and Authentication
  • Implementing Basic Authentication
  • Writing a Classifier
  • Machine Learning Vocabulary
  • Introduction to Machine Learning
  • Give and Receive Feedback
  • Treehouse Club - CSS
  • Creating an SVG
  • Introduction to SVG
  • Choosing Options
  • Organizing Forms
  • Form Basics
  • Structuring Tables
  • Table Basics
  • Captioning Video
  • Express Middleware
  • Sessions and Cookies
  • User Registration and Login
  • What is Authentication?
  • Positioning Page Content
  • CSS Layout Project
  • Page Layout with the Float Property
  • Controlling Layout with CSS Display Modes
  • Getting Started with CSS Layout
  • Fundamental Concepts
  • Designing with the Latest Features
  • Basic Layout
  • The Box Model
  • Media Basics
  • Understanding Values and Units
  • Basic Selectors
  • Getting Started with CSS
  • Going Further with HTML
  • Images, Text and Links
  • Structuring Your Content
  • Getting Started With HTML
  • Planning for Performance
  • Measuring Performance
  • Optimize Assets
  • Combine and Minify Assets
  • Adding a New Web Page
  • HTML: The Structural Foundation of Web Pages and Applications
  • Make It Beautiful with CSS
  • Getting Familiar with HTML and CSS
  • Performing CRUD Operations
  • Defining Models
  • Getting Started with Sequelize
  • 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
  • Refactoring and Modularizing a REST API
  • Create, Read, Update, Delete
  • Managing Data and Asynchronous Code
  • Getting to Know REST APIs
  • Asynchronous Code in Express
  • Serving Static Files in Express
  • Applying Express Knowledge
  • Middleware
  • Deeper into Routing with Express
  • Using Templates with Express
  • Getting Started with Express
  • 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
  • Creating a Command Line Weather Application
  • Handling Errors in Node
  • Getting Data From an API With Node
  • Introduction to Node.js
  • Adding the Game Logic
  • Making the Game Interactive
  • Rendering the Game
  •  Building Constructor Methods and Generating Objects
  • Introducing 'Four in a Row'
  • Getters and Setters
  • Working with Classes in JavaScript
  • Object Basics
  • Introduction to Object-Oriented JavaScript
  • Exploring Async/Await
  • Understanding Promises
  • Asynchronous JavaScript with Callbacks
  • What is Asynchronous Programming?
  • Programming AJAX
  • AJAX Concepts
  • Working with jQuery Collections (2017)
  • Understanding jQuery Events and DOM Traversal (2017)
  • Introducing jQuery (2017)
  • Improving the Application Code
  • Editing and Filtering Names
  • Adding and Removing Names
  • Traversing the DOM
  • Responding to User Interaction
  • Making Changes to the DOM
  • Getting a Handle on the DOM
  • The Browser Environment
  • Defining Variables With let and const
  • Using Template Literals
  • Create Function Using Arrow Syntax
  • JavaScript is Everywhere
  • JavaScript Tools and Workflows
  • JavaScript Loops
  • JavaScript Arrays
  • JavaScript Objects
  • JavaScript Numbers
  • JavaScript Conditional Statements
  • JavaScript Functions
  • Introducing JavaScript
  • JavaScript Variables
  • Introducing JavaScript
  • Finishing the Game
  • Newbie