Free Interactive Demos

Experience Learning by Doing

Try our interactive simulators for free. No sign-up required. See how RuntimeVisuals turns abstract concepts into visual, hands-on learning experiences.

Available Demos

Each demo showcases the interactive simulator experience you'll find throughout our deep dives.

How to Get the Most Out of These Demos

1

Start with Theory. Read the concepts first to understand what you're about to see.

2

Step slowly. Use the step buttons, don't just auto-play. Let each state sink in.

3

Read twice. Check the description, then look at the visualization. Repeat.

4

Reset & replay. Run it multiple times until you can predict the next state.

Client App
code_verifier (secret)
code_challenge
Auth Server
Intercept attack blocked
OAuth Security

PKCE Flow Simulator

Watch how PKCE (Proof Key for Code Exchange) protects mobile apps and SPAs from authorization code interception attacks. Toggle between normal flow and attack mode to see exactly why the cryptographic proof makes stolen codes worthless.

Normal & Attack Modes
Crypto Proof Breakdown
HTTP Protocol View
Step-by-step Execution
Launch Demo No sign-up required
Algorithms

Sorting Algorithm Visualizer

Step through 5 classic sorting algorithms and watch them execute in real-time. See comparisons, swaps, and understand why some algorithms outperform others in different scenarios.

5 Sorting Algorithms
Step-by-step Control
Launch Demo No sign-up required
Microtask Queue
Promise.then
queueMicro
Macrotask Queue
setTimeout
waiting...
Drain ALL before next macro
JavaScript Internals

Microtask Drain Rule Visualizer

Finally understand why Promise.then() runs before setTimeout(..., 0). Watch the event loop drain the microtask queue completely before picking any macrotask.

4 Drain Scenarios
Step-by-step Execution
Queue State Visualization
Console Output Trace
Launch Demo No sign-up required

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