LLD
Interactive UML class diagram
Classes, methods, relations and patterns.
User
- id: string
- name: string
- email: string
+ getProfile()
+ updateProfile()
Playlist
- id: string
- name: string
- songs: List
+ addSong()
+ removeSong()
11..*
AI-powered • LLD • HLD • DSA • Design Patterns
Design any system.
Understand every decision.
Describe an idea or interview problem, get a clear specification, and explore interactive LLD, HLD and DSA views with explanations.
Static illustration of the three workspace views. It is not your model.
RateLimiterclass
- windowSeconds: number
- maxRequests: number
- store: TokenBucket
+ allow(key: string): boolean
+ getRateLimitInfo(key: string)
<interface>RateLimitStore
+ get(key: string)
+ set(key: string)
+ increment(key: string)
Strategy Pattern
Used to support different rate limiting algorithms (e.g. Token Bucket, Fixed Window, Leaky Bucket).
TokenBucketclass
- capacity: number
- tokens: number
- lastRefill: Date
+ consume(): boolean
+ refill(): void
What you get
A complete, structured breakdown with explanations and trade-offs.
HLD
System architecture walkthrough
Components, flows, scaling and failure modes.
Client
Load Balancer
Auth Service
User Service
Playlist Service
↓↓↓
PostgreSQL
Redis
Message Queue
DSA
Operation-focused analysis
Structures, algorithms and trade-offs.
Find nearest users
Data Structure:Geohash + HashMap
Time Complexity:O(1) lookup
Space Complexity:O(n)
Why: Efficient geo-based lookup for nearby users without bounding box overhead.
Alternatives: R-Tree (better for range queries), QuadTree (spatial partitioning).
How it works
From a simple idea to a complete architecture in minutes.
1
Describe your idea
Enter a vague prompt or detailed specification.
2
Review requirements
Edit functional and non-functional requirements.
3
Generate architecture
Get LLD, HLD and DSA based on your requirements.
4
Explore and learn
Interactive diagrams with guided explanations.
Controls, keys and export
Build • Learn • Improve
Ready to design your next system?
Start from one idea, confirm the spec, then inspect the model and the trade-offs it explains.
LLD
Class diagrams & patterns
HLD
Architecture & scaling
DSA
Algorithms & complexity