30 days of gamified AI prep, live interview practice, and a real RAG capstone

For students and professionals preparing for AI interviews. Master RAG, agents, evals and system design. No CS degree needed.

learn it · build it · rehearse it, till it feels easy.
✓ Free forever: 23 Foundations cards, daily boss, 2-min voice taste · ✓ No credit card
600+interview questions & answers
105concept cards + 42 hands-on code labs
7+a growing community across 7+ countries
The real stack you'll build with
LangChainLangGraphMCPFAISSHugging FacePyTorchvLLMRAGAS
The problem

You’ve watched the tutorials. The interview still feels like a coin flip.

I don't know where to start.
Tutorials don't stick.
I can explain it but can't build it.
The interview catches me off guard.
RAG, agents, evals. What actually matters?
I get stuck and there's no one to ask.

And you’ve tried the usual fixes:

Another course binge at 2am.
The 4-hour YouTube video you never finished.
One more certificate nobody reads.

Watching feels like progress. Then a real interviewer asks “why?” and none of it is there.

The method

The interview math is simple.

recall× build× rehearse
=
the offer

It multiplies. Train all three, a little every day.

Not too late
Demand for AI engineers still outruns supply.
Portfolio > degree
A shipped project beats a certificate.
No heavy math
Applied and Python-first, start to finish.
Free to try
Foundations costs nothing, forever.
How it works

Three moves, repeated until it's automatic.

01

Learn by retrieving

Every concept starts as a question you answer from memory. Then the full explanation opens, and the AI tells you how close you were.

⚡ Day 12 · recallAGENTS
How does an LLM agent work, and what is the ReAct loop?
an intern who keeps using tools and checking results until the task is done
Flip card ⟳
The answer

An agent works in a loop: think, call a tool, look at the result, and repeat until it can answer.

THOUGHT ACTION OBSERVATION
Tool calling

The model decides when a tool is needed. It emits the function name plus JSON arguments; the calling code runs it and hands the result back.

resp = client.messages.create( model=model, tools=tools, messages=msgs) if resp.stop_reason == "tool_use": result = get_weather(**call.input) msgs += tool_result(call.id, result)
One round of the loop
MODEL TOOL RESULT
Beyond single agents

Planner-executor pairs, multi-agent crews and memory extend the pattern. Guardrails and step limits stop runaway loops.

Your turn · recall it
1 · What is an LLM actually doing?
predicting the next token, again and again
2 · Why can it sound sure and still be wrong?
it completes patterns, it doesn't look facts up
3 · What is a token?
a word-piece, the unit it predicts
Submit ↵ AI score 5/5 · +40 XP ✓
02

Build it by hand

The same concept then becomes a small Python program. You run it right in the browser, and the tests tell you if it really works.

agent_loop.py
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tools = [weather_tool] resp = llm.create(tools=tools, msgs=msgs) if resp.stop_reason == "tool_use":   result = get_weather(**call.input)   msgs += tool_result(call.id, result)   resp = llm.create(tools=tools, msgs=msgs) print(resp.text)
▶ Run tests✶ 3/3 passing · +30 XP
Passed ✓
03

Rehearse out loud

Interviews are spoken. The last mile is a daily warm-up round, a role-specific deep dive, and a live voice interview.

⚔️ Daily Boss45 XP · avg 4.2
Question 2 of 3
In the ReAct loop, what follows an Action?
an Observation, the tool's result feeds the next thought
★★★★☆strong recall · +15 XP
🎯 Tailored Interviewyour target role
Choose your interview room
🏗️ Big-Tech ML Infra
🔬 AI-Lab / Research
🚀 AI Startup / Product
🚀 AI Startup room · Question 1 of 3
Your JD mentions LangGraph. Design the agent loop for a support bot.
a state graph: retrieve node, tool node, grader edge…
12:47 Listening…
“Walk me through a tool-calling agent, and where it breaks.”
Daily bossTailoredVoice
INSIDE THE PLATFORM

FOUR TOOLS. ONE PLATFORM.

Learn it, build it, rehearse it, ship it. Every surface you need to get interview-ready, without leaving the page.

1 Learn

Active-recall cards, in Story or Focus mode, with an AI tutor.

You don't re-read. You retrieve, and an AI grades you. Flip any card between Story mode , an illustrated walkthrough, and Focus mode, a fast deep dive with diagrams, real Python and a tutor. Then rehearse the real interview questions out loud.

Focus mode — the real card: one-line definition, core loop, a next-token odds diagram and real Python
Story mode : the whole idea, as an illustrated walkthrough
🎤
Interview questions on every card : practice out loud: “Walk me through the autoregressive loop.” · “Why isn't an LLM a database?”
2 Code

A built-in Python IDE.

Read the problem, write the solution, run live tests, right here. Build the real things by hand, from a softmax to a LangChain RAG chain, with zero local setup. This is the app's actual Code screen.

Code arena

3 / 18 solved RAG · retrieval chain ▾
◇ Problem Applied · +40 XP
Build a RAG chain
Retrieve the top-k chunks, ground the prompt in them, and answer.
solution.py
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from langchain_openai import ChatOpenAI, OpenAIEmbeddings from langchain_community.vectorstores import FAISS from langchain.text_splitter import RecursiveCharacterTextSplitter emb = OpenAIEmbeddings(model="text-embedding-3-small") store = FAISS.load_local("docs_index", emb) llm = ChatOpenAI(model="gpt-4o-mini", temperature=0) def rag_answer(query, k=4): docs = store.similarity_search(query, k=k) context = "\n\n".join(d.page_content for d in docs) prompt = f"Context:\n{context}\n\nQ: {query}\nA:" return llm.invoke(prompt).content # next: rerank, cite sources, stream tokens…
▶ Run tests ✦ tests passing · +40 XP
3 Interview

Live voice mock interviews.

Speak your answers out loud to an AI interviewer, the way the real room works. Get scored and corrected in real time, on quick daily drills or a full timed mock.

12:47 Speaking…
“Walk me through self-attention. How do Q, K and V interact?”
4 Build

A real RAG system, end to end.

A 5-part capstone on a live LangChain kernel: build retrieval → add agents (LangGraph, MCP) → make it trustworthy with evals → ship it with FastAPI. A real project you can talk through in any interview.

✓Overview
✓Why one fails
✓Lexical
✓Semantic
✓Hybrid
6Rerank
7Rewrite
8Faithfulness
9Assemble
10Evaluate
Course 2 · Stage 6 · Rerank

Reorder so the best chunk is first

  1. Hybrid search got the right chunk into the shortlist.
  2. Score each candidate: cross_encoder.score(query, doc)
  3. Sort by that score, highest first. Keep the top_n.
  4. The starter returns arrival order. The grader will notice.
rerank.py# real Python · live kernel
def rerank(query, docs, top_n): # your code goes here: score, sort, keep top_n return docs[:top_n]
▶ Run my codepass it to unlock the interview answer ↓
Interviewbi-encoder vs cross-encoder · a favorite
"What's a reranker, why a cross-encoder, and how does it differ from the embedding retrieval you already have?"
🔒 Pass the cell above to unlock this answer
Try it inside
THE WHOLE COURSE, ONE PICTURE

By day 30, you can explain every station of this machine.

Tokens, embeddings, attention, retrieval, generation. Scroll and watch a question become an answer. Each stop is a card, a lab and an interview question you'll have handled.

the question sets off Who won the World Cup? Who won World Cup? FIFA 2022: ARG searchverifyanswer INPUT Who won theFIFA World Cup 2022? 1 TOKENIZATION 2 EMBEDDINGS [0.21, -0.31, ...] 3 ATTENTION Who won the FIFA World Cup 2022 ? 4 TRANSFORMERLAYERS 5 REASONING KNOWLEDGE BASE 6 RAG(RETRIEVAL) 7 AGENT LAYER Search docs✓ Compute✓ Verify✓ Answer✓ CALCULATOR BROWSER TERMINAL DATABASE >_ 8 OUTPUT(VOICE / API) {..} Argentina won theFIFA World Cup 2022,defeating France.✓ POST /api/answer { "answer":"Argentina won theFIFA World Cup 2022." }
Start the 30 days
THE 30-DAY ROADMAP

Foundations → Applied → Advanced.
In order.

Master the cards, clear the boss, move up. These are the real tier books from your dashboard, click a book to open it.

Foundations

How LLMs work under the hood: text becomes tokens, tokens become vectors, vectors become predictions.

  • ✓ Tokenization & vocabularies
  • ✓ Embeddings & vector space
  • ✓ Sampling & decoding
  • …and more topics

FOUNDATIONS

Tier 1 · the vocabulary everything stands on

Tap to open
Applied

Turn the fundamentals into working systems: attention at scale, RAG, tool use, and how to evaluate what you build.

  • ✓ Attention & KV-cache
  • ✓ RAG pipelines
  • ✓ Tooling & evals
  • …and more topics

APPLIED

Tier 2 · applied LLM engineering

Tap to open
Advanced

Ship it: quantization, efficient serving, deployment, and the systems-design thinking interviews probe hardest.

  • ✓ Quantization
  • ✓ Serving & inference
  • ✓ Deploy & scale
  • …and more topics

ADVANCED

Tier 3 · systems & deployment

Tap to open
Start at Foundations
WHAT DECIDES THE OFFER

Questions interviewers love to ask. Practice them until they feel easy.

These come up in real AI interviews all the time. In 30 days each one is just another rep.

RAGday 30 · ✓

“The retriever finds the right doc but the model still hallucinates. What do you check?”

Chunking, reranking, context order and grounding. You'll have built each layer yourself.

SYSTEM DESIGNday 30 · ✓

“RAG vs fine-tuning vs long-context. When do you reach for which?”

A decision you'll have made hands-on, with your own results to point to.

EVALSday 30 · ✓

“How do you evaluate a RAG system with no ground-truth labels?”

LLM-as-judge, RAGAS, faithfulness. Drilled until it's yours in the evals tier.

AGENTSday 30 · ✓

“Walk me through a tool-calling agent, and where it breaks.”

Tool-calling, LangGraph, MCP, and agent memory, built and rehearsed.

Get the answers
Watch a real interview

This is what rehearsing sounds like.

A recorded session with the same AI interviewer you'll practice with. Warm on purpose, and it asks follow-ups on whatever you say.

Rehearse like this
Where we fit

The interview layer video courses skip, without the bootcamp price.

An honest look. Bootcamps still win on live mentors and placement, and that's what their price buys. On everything you can do yourself, tonight, Skillumen wins on speed, price, and the parts that make it stick.

Video coursesrecorded · watch & forget
★ that's usSkillumenlearn → build → interview-ready
Bootcampslive cohort · months-long
How you learn
Passive video
Recall · build · rehearse
Live cohort, set dates
AI voice mock interviews
✗
✓up to 15, with detailed report
✗
Memory-based recall (spaced repetition)
✗
✓
✗
Build labs + a real RAG capstone
✗
✓
✓
RAG · agents · evals · LLMOps, current
~often stale
✓
✓
Start tonight, no fixed cohort
✓
✓
✗
See the price, no sales call
✓
✓
✗
Live mentor + job placement
✗
✗
✓

The honest trade: bootcamps buy you a live mentor and a placement cell. Skillumen buys you the mocks, recall, and shipped capstone that get you interview-ready — flexible, transparent, for a fraction of the price.

Start free
Question bank

Practice the questions that actually get asked.

Built from real interview gaps across recall, code, and voice mocks.

codeImplement multi-head attention from scratchrecallWhy does RAG retrieval fail and how do you fix itvoiceWalk me through KV-cache memory costrecallExplain temperature vs top-pcodeImplement multi-head attention from scratchrecallWhy does RAG retrieval fail and how do you fix itvoiceWalk me through KV-cache memory costrecallExplain temperature vs top-p
voiceHow would you shrink an LLM's latency budgetcodeWrite a batched softmax with numerical stabilityrecallWhat breaks first when context length growsrecallCompare LoRA vs full fine-tuningvoiceHow would you shrink an LLM's latency budgetcodeWrite a batched softmax with numerical stabilityrecallWhat breaks first when context length growsrecallCompare LoRA vs full fine-tuning
FAQ

Before you commit.

Straight answers to the doubts that keep aspiring AI engineers up at night.

01

Is it too late? Isn't AI saturated?

No. Demand still outruns supply for people who can actually build. Employers want a shipped RAG or agent project, not one more certificate.

02

No CS degree, and my math is rusty?

It's fine, this is applied engineering, not research. If you can write Python you're in; we skip the heavy math. A portfolio beats a diploma here.

03

Isn't prompt engineering dead?

The title faded; the skills grew up into AI engineering. You'll learn RAG, agents (LangGraph/MCP), evals and LLMOps, the things interviews test now.

04

How is this different from a Udemy course?

You retrieve instead of re-watch, build the primitives by hand, get AI-graded, and ship a deployed capstone. Built against tutorial hell.

05

Will I actually ship something?

Yes. A deployed capstone plus hands-on labs (softmax, attention, a RAG pipeline) you write yourself, not copy.

06

Does it cover RAG, agents and evals, or just theory?

Deep on all three: RAG (chunking, reranking, hybrid), agents (tool-calling, LangGraph, MCP), evals (LLM-as-judge, RAGAS), plus LLMOps & observability.

07

Won't it be outdated? LangChain changes monthly.

We teach durable patterns with swappable tooling, refreshed for 2026. A library bump doesn't reset what you know.

08

Is it real interview prep?

Voice mocks plus question banks built from the gaps candidates actually miss : RAG, agentic AI, and system design.

09

Can I finish the whole course in 30 days?

Yes. The cards and recall challenges are paced to finish in about a month, and you work in your own order, at your own speed. Prefer no deadline? The Self-Paced pass gives you lifetime access.

10

What if it’s not for me?

You’ll know before you pay: Foundations is free forever . It's the real platform. Go deeper with Applied, Advanced or Self-Paced when you're ready, no lock-in, no sales call.

Choose your plan

Start free. Go job-ready when you are.

The interview layer video courses skip : AI voice mocks, memory-based recall and a real RAG capstone, at a fraction of a bootcamp's price. Foundations free forever.

✓ Start free · no card to start · no sales call
Foundations
Freeforever
No card required
Master the fundamentals, free.
  • All Foundations (Tier 1) cards
  • Interview questions on every card
  • Tier-1 coding challenges
  • Daily Boss challenge
  • Active recall + AI grading
  • AI tutor on every card
Applied
₹1,499
one payment · 30-day pass
The skills that get you hired.
  • Everything in Foundations
  • Applied cards: RAG, agents, fine-tuning, evals
  • Applied interview questions + tailored drills
  • Tier-2 IDE build labs (RAG chain, agent)
  • 2 AI voice interviews
Best value
Advanced
₹2,999
one payment · 30-day pass
Everything to land the offer.
  • Everything in Applied
  • Advanced cards: LLMOps, MCP, vLLM, system design
  • Real-gap interview question banks
  • Tier-3 coding + 5-part RAG capstone (build → agents → evals → deploy)
  • 5 AI voice interviews
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