SYSTEM//DEEP DIVE Progress
INTERACTIVE ENGINEERING FIGURES /// BUILT FOR INTERVIEWS

Stop reading about systems.
Run them.

Every chapter is a figure you drive: predict what happens, execute it, watch the machine react, keep the picture. HashMaps resize under your cursor. Thread pools reject your tasks. Garbage collectors sweep while you watch.
Start Core Java →Spring, early access
21 LIVE FIGURES★★★ RANKED BY REAL INTERVIEWS3 LEVELS PER FIGURE
COURSES
01
OPEN · INTERVIEW PREP MODE
Core Java
The language and the JVM: collections, strings, concurrency, memory, garbage collection. Every three-star interview chapter has a live figure.
ENTER→
 02
EARLY ACCESS
Spring & Spring Boot
Proxies, transactions, and the N+1 problem, with the container's magic drawn as machinery you can step through.
ENTER→
 03
IN PLANNING
System Design
Queues, caches, and consistency, enacted the same way: as figures that run.
COMING
 04
IN PLANNING
AWS
The building blocks behind the console, from IAM to VPC networking.
COMING
 05
IN PLANNING
Docker & Microservices
Images, layers, networks, and the failure modes of splitting a system.
COMING
 06
IN PLANNING
C++
Memory, ownership, and the machine underneath the syntax.
COMING
MODE 1 /// INTERVIEW PREP · BUILDS FIRST
Chapters ranked by how often they come up in real interviews, most-asked first, rated ★★★ to ★. Finish a chapter's levels and you can answer it cold; prove it in a test-out and skip ahead.
MODE 2 /// COURSE MODE · FOLLOWS
The complete A to Z syllabus of each course, for learning from scratch in order. In production now.
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