Codemia

Codemia is a practice platform built specifically for software engineers preparing for technical interviews. It focuses on the areas that are notoriously difficult to study passively: system design, object-oriented design (OOD), and data structures & algorithms (DSA). Instead of just reading articles, you work on problems using an interactive whiteboard, breaking down requirements, estimating scale, and drafting high-level designs, much like you would in a real interview.

What sets Codemia apart is its active, hands-on approach. For system design, you get over 120 problems where you can draft your solution and receive AI-powered evaluation and coaching. The DSA section includes over 300 problems with step-by-step visualizations to help you see how algorithms work. Newer sections let you practice designing Agentic AI systems and participate in peer-to-peer mock interviews with video calls and a collaborative whiteboard. The platform provides editorial solutions and lets you view other users' submissions for learning.

This tool is a direct fit for software engineers at any level who are actively job hunting, especially those targeting roles at major tech companies. It's useful for mid-level engineers prepping for system design rounds, new graduates drilling coding problems, or anyone who wants to move beyond theoretical study to applied practice in a low-pressure environment.