Learn CS the right way. For free.
SkillUP is a free, structured learning platform for developers. Study DSA, system design, fullstack, and AI through curated video tracks — with an AI mentor that resolves your doubts inside the video player.
Why SkillUP
Everything you need to go from beginner to job-ready
Structured Curriculum
Every track follows a carefully sequenced roadmap — no random playlists, just deliberate progression from fundamentals to advanced.
In-Player AI Mentor
Ask doubts directly inside the video player. The AI understands the exact concept being taught and answers in context.
Downloadable Notes
Each lecture comes with concise PDF notes and code cheatsheets — perfect for revision before interviews.
100% Free, Forever
No subscriptions, no paywalls, no credit card required. Quality CS education should be accessible to everyone.
Learning Tracks
Structured roadmaps for real engineering roles
Each track is sequenced from first principles to interview-level depth.
Data Structures & Algorithms
Arrays · Trees · Graphs · DP · Recursion
Fullstack Development
Next.js · React · TypeScript · REST APIs
Backend Engineering
Node.js · PostgreSQL · Redis · Kafka
System Design
HLD · LLD · Sharding · CAP Theorem
AI & Generative AI
RAG · LangChain · Embeddings · Agents
DevOps & Cloud
Docker · Kubernetes · AWS · CI/CD
AI Mentor
Ask questions inside the video — get answers in context
The AI Mentor lives inside every lecture. It knows exactly what concept is being taught at that moment — so when you ask a question, you get a precise, contextual answer, not a generic one.
- Understands the active lecture topic
- Explains code line by line on demand
- Gives interview-ready summaries
- Remembers your session history
AI Mentor
Nested loops give O(n²) time. Since the array is sorted, two pointers let us evaluate all valid pairs from both ends in O(n) time with O(1) space — much more efficient for large inputs.
function twoSum(arr, target) {
let l = 0, r = arr.length - 1;
while (l < r) {
const sum = arr[l] + arr[r];
if (sum === target) return [l, r];
sum < target ? l++ : r--;
}
}Learner Stories
From the community
“The AI Mentor next to the DSA lectures resolved my doubts instantly. Cracked Microsoft in 3 months of focused prep.”
Aarav S.
SDE-2 @ Microsoft
“No paywalls, clean playlists, downloadable notes and an AI that actually understands the lecture context. Nothing else comes close.”
Pooja V.
Fullstack Dev @ Swiggy
“The distributed systems and Redis tracks are gold. Smooth experience, zero distractions, and completely free.”
Rohan D.
Backend Eng @ Razorpay
FAQ