Rohald van Merode
seal-mask

Rohald van Merode

Treehouse Staff

Amsterdam, Netherlands
Open to Work

67,252

Total Points

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Skills & Experience

  • Spoken Languages

    • Dutch
    • English

488 Achievements

  • Unit Converter
  • Getting to Know PHP
  • Efficiency!
  • Exploring the Java Collections Framework
  • Organizing Data
  • Getting There
  • Building Your Resume
  • The Time Tracker
  • The Birthday App
  • Date and Time Basics
  • Introduction
  • Python: Instant Objects
  • Python File Systems Project Starter
  • Python File Systems Manipulation
  • Python File Systems Navigation
  • Understanding State
  • Introducing Props
  • Thinking in Components
  • First Steps in React
  • Building a Platform Game with Phaser
  • Building a Breakout Game with Phaser
  • Persisting Data with Hibernate
  • Getting Started with Hibernate
  • Data Persistence & ORMs
  • Writing Your Own Java Annotation
  • Using Java's Built-In Annotations
  • Bells and Whistles
  • CSS Fundamentals
  • HTML Fundamentals
  • Getting Familiar with HTML and CSS
  • Diving into Web Development
  • Advanced Tooling
  • IDE Exploration
  • How it Works
  • Java Maps
  • Java Lists
  • Generics in Java
  • Interfaces in Java
  • Java Inheritance
  • Introducing IntelliJ and Unpacking Packages
  • Gotchas and Wins
  • Iteration
  • Creation
  • Harnessing the Power of Objects
  • Day 3: Getting Creative
  • Day 2: Advanced Selecting
  • Day 1: Joining Tables
  • Orientation: Selecting Data
  • Date and Time Functions
  • Aggregate and Numeric Functions
  • Working with Text
  • Ordering, Limiting and Paging Results
  • Additional Scraping Tasks
  • A World Full of Spiders
  • Introducing Data Scraping
  • Writing a Classifier
  • Machine Learning Vocabulary
  • Introduction to Machine Learning
  • Big Data at Netflix
  • Where and How Big Data Is Used
  • What is Big Data
  • The Data Analysis Process
  • Getting to Know Your Data
  • Introducing Data Analysis
  • Design Patterns
  • Page Layout
  • Going Further with Type
  • Laying Out Type
  • Web Typography
  • How to Choose and Use Fonts
  • Introduction to Typography
  • Chrome DevTools Basics
  • Combine and Minify Assets
  • Optimize Assets
  • API Protection
  • Resourceful Blueprints
  • Gettin' CRUD-y With It
  • Our Diary App
  • Meet Peewee
  • Dice Roller
  • Python: Advanced Objects
  • Python: Inheritance
  • Python: Instant Objects
  • Optimization Best Practices
  • Asset Optimization
  • Why Web Performance Matters
  • Testing for Accessibility
  • Mobile Accessibility
  • Accessible UI Patterns
  • Semantic HTML and WAI-ARIA
  • WCAG 2.0 (and Other Standards)
  • Access for Everybody
  • Scrum Artifacts
  • Scrum Events
  • Introducing Scrum
  • What is Agile?
  • Build Your Professional Portfolio
  • Use LinkedIn to Grow Your Network
  • Film Your Pitch Video
  • Character Builder
  • Flask Templates
  • Welcome to Flask
  • Review Your Checklist with an Advisor
  • Next Steps
  • Improving Our Tests
  • Behavior Driven Development with Mocha & Chai
  • Express Middleware
  • Sessions and Cookies
  • User Registration and Login
  • Introducing Unit Testing
  • What is Authentication?
  • Refining the App
  • Building the Application
  • Setting up with Create React App
  • Practice forEach
  • React Router and Authentication
  • Implementing Basic Authentication
  • Introducing the Authentication Project
  • How to Critique Design
  • InControl Conference
  • LEGO
  • Data Cleaning
  • Understanding Cleaning Data
  • Python Regular Expressions
  • Practicing Data Visualization
  • Line and Area Charts, Scatter Plots, and Maps
  • Bar Charts, Histograms, and Pie Charts
  • Data Visualization Fundamentals
  • Seaborn Data Visualization Challenges
  • Plotting Functions
  • Introduction to Seaborn
  • What to Test
  • How To Test
  • Why Test
  • The Internet
  • Building a Flashcard App
  • Sweeping Vues: Loops, Methods, Directives
  • What a Beautiful Vue!
  • Introducing Vue
  • Modular Media Queries
  • Sass Grid System
  • SMACSS and Sass
  • Sass and BEM
  • Getting Modular with Mixins and Functions
  • Treehouse Club - CSS
  • Debugging, Best Practices, and Production
  • Refactoring with Sass
  • Art Direction with the Picture Element
  • Image Delivery with Srcset and Sizes
  • Welcome to the Treehouse Club
  • Captioning Video
  • Media Basics
  • Telling the Story
  • Designing for your User’s "To-be"
  • Understanding your User’s “As-is” Scenario
  • Becoming Acquainted with Your User
  • Becoming a Design Thinker
  • HTTP Methods and Headers
  • Creating a Basic Template Engine in Node.js
  • Handling Routes in Node.js
  • Creating a Simple Server in Node.js
  • Practicing Object Basics
  • Practicing Getters and Setters
  • Practicing Classes
  • Checking Out and Returning a Book
  • Starting with Some Methods
  • The Rough Plan
  • React Component Patterns
  • Stateful Components and the Effect Hook
  • Managing State
  • Data Flow
  • Build Modular Interfaces with Components
  • Making Changes to the DOM
  • Getting a Handle on the DOM
  • The Browser Environment
  • Creating a Command Line Application
  • Handling Errors in Node
  • Getting Data From an API With Node
  • Introduction to Node.js
  • Going Further with Routing
  • Navigating, Nesting and Redirecting Routes
  • Getting Started with React Router
  • Data Eruption
  • Chart Toppers
  • Getting Started with Data Visualization
  • Welcome to Basic Statistics for Data Analysis
  • Functions in TypeScript
  • Manipulating Types
  • Working with (More) Types
  • Getting Started with TypeScript
  • Exploring pandas
  • Meet pandas
  • Array Programming
  • Array Organization
  • Meet NumPy
  • Subqueries
  • Set Operations
  • Joining Table Data with SQL
  • Table Relationships
  • Database Keys
  • Database Normalization
  • Build a Spreadsheet
  • Spreadsheet Best Practices
  • Spreadsheet Functions & Formulas
  • Getting Started With Spreadsheets
  • Introducing Spreadsheets
  • Welcome to Basic Math for Data Analysis
  • Objects in Action - Immersive Review
  • Coding Machine
  • 150th Techdegree Peer Review
  • Code Racer
  • Mike the Frog
  • Treehouse Staff
  • Tools of the Trade
  • Breaking Down Data Analysis
  • Connecting to a Database with SQLAlchemy
  • Creating a Basic Website with Flask
  • Working with SQLAlchemy
  • Imposter Syndrome
  • Create Function Using Arrow Syntax
  • Using Template Literals
  • Defining Variables With let and const
  • Classes
  • Objects and New Collection Types
  • The Cooler Parts of ES2015
  • ES2015 Basics
  • Treehouse Club - JavaScript
  • Traversing the DOM
  • Managing Packages with NPM
  • Hello Node.js
  • CSS Media Queries
  • CSS Layout Techniques
  • Box Model Concepts
  • The CSS Box Model
  • Finishing Touches
  • Styling Images
  • Styling Boxes
  • Styling Text
  • Fundamental Concepts
  • Understanding Values and Units
  • Basic Selectors
  • Getting Started with CSS
  • Mobile-First CSS Layout
  • Introduction to SQLAlchemy
  • Timezones
  • Math Quiz App
  • Dates and Times
  • Creating a Memory Game
  • Emulating Built-ins
  • Welcome to OOP
  • Technical Interview Prep: Basic Python
  • Buggy Logs
  • You as a Mentee
  • Cleaner Code
  • Practice Functions
  • Treehouse Festival 2021
  • Exterminator
  • 100 Days of Code
  • React Router and Authentication
  • Implementing Basic Authentication
  • Introducing the Authentication Project
  • Get Involved in Open Source
  •  Create a Web Presence on GitHub
  •  Working on a Team
  • Working By Yourself
  • Hello, GitHub!
  • Validating Data
  • The Importance of Data Validation
  • Retrieve Related Data in Sequelize Queries
  • Create Related Data Using Sequelize Models
  • Data Relationships in Sequelize
  • Understand Data Relationships
  • Refactoring and Modularizing a REST API
  • Create, Read, Update, Delete
  • Managing Data and Asynchronous Code
  • Getting to Know REST APIs
  • Getting the REST You Need 2
  • Performing CRUD Operations
  • Defining Models
  • Getting Started with Sequelize
  • Asynchronous Code in Express
  • Handling Errors When Manipulating Data
  • Deleting Data from a Database
  • Updating Data in a Database
  • Adding Data to a Database
  • Going Further with Routing
  • Navigating, Nesting and Redirecting Routes
  • Getting Started with React Router
  • Treehouse Festival (December 2020)
  • React Component Patterns
  • Stateful Components and Lifecycle Methods
  • Managing State and Data Flow
  • Build Modular Interfaces with Components
  • Stateful Components
  • Introducing Props
  • Thinking in Components
  • First Steps in React
  • 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?
  • Creating a Command Line Weather Application
  • Handling Errors in Node
  • Getting Data From an API With Node
  • Introduction to Node.js
  • JavaScript Frameworks, Libraries, and Developer Roles
  • JavaScript Outside of the Browser
  • GET and POST Requests in a Browser
  • Introduction to HTTP
  • Adding the Game Logic
  • Making the Game Interactive
  • Rendering the Game
  •  Building Constructor Methods and Generating Objects
  • Introducing 'Four in a Row'
  • Reformatting User Input
  • Validating a Form with Regular Expressions
  • Regular Expressions
  • Build an Accessible Form
  • Introduction To Accessibility
  • The Role of Selectors in JavaScript
  • Pseudo-classes and Combinators
  • Selector Basics
  • Multidimensional Arrays
  • Loop Through Arrays
  • Store Multiple Values in an Array
  • Loop Through Objects
  • Object Basics
  • Working with 'for' Loops
  • Simplify Repetitive Tasks with Loops
  • Installing Sass and Setting up the Project
  • Treehouse Festival
  • Principles of Design
  • Elements of Design
  • Combining Array Methods
  • Array Manipulation
  • Array Iteration
  • Exploring Async/Await
  • Understanding Promises
  • Asynchronous JavaScript with Callbacks
  • What is Asynchronous Programming?
  • Programming AJAX
  • AJAX Concepts
  • Callbacks and the DOM
  • Callbacks with Timers
  • Introduction to Callback Functions
  • Getters and Setters
  • 100th Techdegree Peer Review
  • Working with Classes in JavaScript
  • Object Basics
  • Introduction to Object-Oriented JavaScript
  • 50th Techdegree Peer Review
  • Going Further with Grid Layout
  • Flexible Sized Grids
  • Introducing Grid Layout
  • 5 Star Techdegree Reviewer
  • 25th Techdegree Peer Review
  • 10th Techdegree Peer Review
  • 5th Techdegree Peer Review
  • Keyframe and Line Drawing Animations
  • Transitions and Transforms
  • Creating an SVG
  • Introduction to SVG
  • Improving the Application Code
  • Editing and Filtering Names
  • Adding and Removing Names
  • Using a jQuery Carousel
  • Add a Sticky Navigation Bar
  • Introducing jQuery Plugins
  • 1st Techdegree Peer Review
  • Arrow Functions
  • Pass Information Into Functions
  • Create Reusable Code with Functions
  • The Math Object
  • Working with Numbers
  • Making Decisions in Your Code with Conditional Statements
  • Working With Strings
  • Storing and Tracking Information with Variables
  • Hello, JavaScript!
  • Finishing the Game
  • Introducing JavaScript
  • Add Reusable Logic to Your Sass
  • Write Smart and Efficient CSS with Sass
  • Improve Your Workflow with Sass
  • Getting Started with Sass
  • GitHub and Other Remote Repositories
  • Managing Committed Files
  • First Commits
  • Common Commands
  • Directories and Files
  • The Command Shell
  • Adding 3D Effects with CSS
  • Getting Started with CSS Transforms
  • Transition Timing Functions and Delays
  • Getting Started with CSS Transitions
  • Structuring Tables
  • Table Basics
  • Using Slack Effectively
  • Introducing Slack for the Techdegree
  • JavaScript Objects and Conditionals
  • JavaScript Arrays and Loops
  • JavaScript Functions
  • Data Types and Variables
  • JavaScript Tools and Workflows
  • JavaScript is Everywhere
  • Iterating and Packing with Dictionaries
  • Introducing Dictionaries
  • Sequence Operations
  • Finding the Data You Want
  • Getting Data from a Database
  • Data, Databases and SQL
  • Sequence Iterations
  • Packing and Unpacking
  • Getting Info In and Out of Functions
  • Introduction to Functions
  • Getting to Know Tuples
  • Build an Application
  • Using Lists
  • Meet Lists
  • All Together Now
  • Functions and Looping
  • Types and Branching
  • Meet Python
  • Measuring Performance
  • Planning for Performance
  • Building Forms With Bootstrap
  • Using Bootstrap Components
  • Responsive Layouts With the Bootstrap Grid
  • Getting to Know Bootstrap 4
  • Working with jQuery Collections (2017)
  • Understanding jQuery Events and DOM Traversal (2017)
  • Introducing jQuery (2017)
  • Advanced Selectors
  • Going Further with Attribute Selectors and Pseudo-Classes
  • Selectors - Beyond the Basics
  • Traversing the DOM
  • Responding to User Interaction
  • Making Changes to the DOM
  • Exploration
  • Discovery
  • Getting a Handle on the DOM
  • The Browser Environment
  • JavaScript Objects
  • JavaScript Arrays
  • JavaScript Loops
  • Choosing Options
  • Organizing Forms
  • Form Basics
  • 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
  • Going Further with HTML
  • Images, Text and Links
  • Structuring Your Content
  • Getting Started With HTML
  • 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
  • Meet Objects
  • Perfecting the Prototype
  • Using your New Tools
  • Getting Started with Java
  • Newbie