Arrays & Hashing · Prefix Sum
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Course catalog
Open a course to see its path, from the first lesson to the last.
AWS and Beyond
Build it in your own AWS account, break it on purpose, then fix it.
- Services
- 37
- Lab guides
- 52
- Total time
- ~265h
Data Structures & Algorithms
Step through every problem as a simulation, then write the code.
- Pattern guides
- 98
- Problems
- 469
SQL Mastery with Postgres
Real Postgres in the page. Write the query, then read the plan.
- Chapters
- 13
- Practice problems
- 44
- Total time
- ~23h
Coming soonSystem DesignAPI Design
Introductory pricing Ends 31 December.
For engineers preparing for interviews and the job after them
Built on foundations.
Equipped for production readiness.
- Understand cloud systems practically.
- Build DSA intuition with step-through simulations.
- Defend every design decision and its trade-offs.
- Write SQL for real data, and read the plan it runs.
devuplabs.cloud/docs/dsa/combination-sum-ii
- Recognise the pattern on sightLearn each DSA pattern once through step-by-step visual simulations, so a question you have never seen still looks familiar. Judged editor submissions build the muscle memory. Notes & Recall keep prep rigorous.
- Production AWS before the jobLearn the AWS ecosystem through labs in your own account on the free tier, then take your systems down and bring them back. That hands-on footing is what lets you own systems end to end in your career.
- Reason through designsSkip memorising each question's boxes and presenting them like a seminar. Drill into storage, networking, consistency and failure, weigh the choices, and defend every decision when the interviewer pushes.
- SQL mastery with Postgres, and moreWrite the hard queries on a real Postgres and read the plan it ran to make them fast. Scroll on for every course, what it teaches, and what you walk away with.
Data structures & algorithms
Recognise patterns.Visualise solutions.
Open the coursePictorial walkthroughs make every pointer move, heap eviction and state transition visible before you write the implementation.
- 16
- topics
- 98
- pattern guides
- 469
- problems with step-through simulations
98 patterns, one map
Drag to turn it.
The course covers 98 patterns across 14 topics: Arrays & Hashing (10), Stack (4), Binary Search (8), Sliding Window (9), Linked List (5), Intervals (5), Heaps (8), Binary Trees (7), Graphs (15), Backtracking (5), Trie (4), Greedy (6), Dynamic Programming (9), Bit Manipulation (3).
·
Watch the solution run
Every problem has a simulation you step through, so you see the window close or the stack unwind before you write a line. As each one plays, the map turns to the pattern it is built on.
Stack · Monotonic Stack
Daily Temperatures
Binary Search · Search on Answer
Koko Eating Bananas
Sliding Window · Shortest / Minimum Window
Minimum Window Substring
Linked List · Rewire & Reorder
Reverse Nodes in k-Group
Intervals · Greedy Scheduling
Minimum Platforms
Heaps · Top K
Kth Largest Element
Binary Trees · DFS Return Values
Binary Tree Maximum Path Sum
Graphs · Directed Reachability
Detonate the Maximum Bombs
Backtracking · Combinations
Combination Sum II
Trie · Word Search & Backtracking
Word Search II
Dynamic Programming · Unbounded Knapsack
Coin Change (unbounded route)
Dynamic Programming · Subsequence DP
Longest Common Subsequence
Data Structures & Algorithms
Recall
Ever feel out of touch with DSA, though you cracked offers before? Like an AI model’s context window, the brain lets go of what it does not recall. Every problem you solve, every note you take and every confidence you rate lands in Recall, comes back right before it fades, and shows you which patterns are ready for the interview.
Cloud engineering
Everyone ships on these.
Every lab runs in your own AWS account. You build a working system, prove it works, then break it on purpose and fix it. Finish the course and the Console is familiar ground: you read the metrics before you change anything, you work the CLI the way an SRE does, and you see how the whole system fits together.
- 37
- services
- 52
- lab guides
- ~265h
- lab time
The services
Compute, data, messaging, IAM and observability, used together the way teams run them.
Break it on purpose
A lab ships a broken revision. You watch the health checks fail and ECS roll back on its own.
ecs-lab · us-east-1 · Fargate + ALB
$ users
ALBecs-lab-tg
ecs-lab-app:2
healthy · 8080
ecs-lab-app:2
healthy · 8080
ecs-lab-app:3
unhealthy · 9999
ecs-lab-app:3
unhealthy · 9999
deployment :2 COMPLETEDrequests 18,420 · 5xx 0
A Fargate service behind an ALB, two tasks on revision :2, every request answered.
Run this labDiagrams from the guides
Each guide draws the system before you build it.
my-app:3; capacity providers back the cluster with Fargate or EC2.assignPublicIp=DISABLED, so their image pulls go through a NAT gateway or ECR VPC endpoints. GitHub never touches the VPC: it talks to the ECR and ECS APIs, and the tasks pull the new image themselves.SQL Mastery with Postgres
Read the plan.Change its mind.
A real Postgres, live on the page and loaded with an urban rail network built to have something to find. Write the query, spring the NULL trap on purpose, then open EXPLAIN ANALYZE and watch the planner change its mind when you change one thing.
- 13
- chapters
- 10
- guided query labs
- 44
- practice problems
One lab, start to finish
Write the query, fall into the NULL trap, read the plan, then open psql and check it yourself.
Read a real plan
This is EXPLAIN ANALYZE output from the course: one query, run with the index switched off and then the way the planner wanted. Watch how many pages each one reads.
=> SET enable_indexscan = off; SET enable_bitmapscan = off; EXPLAIN ANALYZE SELECT count(*) FROM ridership.gate_tap WHERE station_id = 431;
Aggregate (actual rows=1.00 loops=1)
Buffers: shared hit=296
-> Append (actual rows=10.00 loops=1)
Buffers: shared hit=296
-> Seq Scan on gate_tap_2026_03 gate_tap_1 (actual rows=4.00 loops=1)
Filter: (station_id = 431)
Rows Removed by Filter: 15463
Buffers: shared hit=153
-> Seq Scan on gate_tap_2026_04 gate_tap_2 (actual rows=6.00 loops=1)
Filter: (station_id = 431)
Rows Removed by Filter: 14527
Buffers: shared hit=143
Cost estimates trimmed. Every actual figure is as Postgres printed it.
gate_tap_2026_03153 pages
index, off
gate_tap_2026_04143 pages
index, off
- Pages read
- 153
- Rows thrown away
- 15,463
With the index switched off, Postgres reads all 153 pages of the March 2026 partition to find 4 rows. The other 15,463 rows it read get thrown away.
Try it in the guideSystem design
Coming soonLearn to think likean architect.
Drill down into system components and their interactions. Build decisions from storage, networking, consistency and failure modes, then explain how those decisions change as the system grows.
- 6
- parts
- 92
- lessons
- 28
- problems and teardowns
Every jump in traffic breaks something
Drag the slider. Each step adds the piece the last setup can't handle, and the course has you say what that piece costs.
Traffic
1K users
Users
CDN
Load balancer
App
App
App
Cache
Database
Shard 1
Shard 3
Read replica
Queue
Workers
Second region
Step 01 · 1K users
One server, one database.
At this size the simple setup is the right one. Ship it and watch the graphs.
What it costs
If that one server goes down, the whole app goes with it.
The interviews this is aimed at
Most of these interviews come down to the same few rounds. Each course rehearses one of them.
- Big tech & AI: Google, Meta, Amazon, Apple, Microsoft, Netflix, Nvidia, OpenAI, Anthropic, Tesla, Adobe, Salesforce, Oracle, Qualcomm, TikTok, ByteDance
- Platforms & infra: Stripe, Databricks, Snowflake, Cloudflare, Atlassian, MongoDB, Confluent, Twilio, ServiceNow, Palantir, Figma, Rippling, Glean, Rubrik, Nutanix, Zscaler, Intuit, Tekion
- Consumer & marketplaces: Uber, Airbnb, Booking.com, Expedia, Agoda, LinkedIn, Spotify, Discord, Pinterest, Snap, DoorDash, Instacart, Lyft, Grab, Shopify, Coupang, Rakuten, eBay, Walmart
- Finance & quant: Jane Street, Citadel, Two Sigma, DE Shaw, Jump Trading, HRT, Tower Research, Optiver, Bloomberg, Goldman Sachs, Morgan Stanley, JP Morgan Chase, Visa, Mastercard, PayPal, Block, Coinbase
- Built in India: Flipkart, PhonePe, Razorpay, Zomato, Swiggy, Zepto, Meesho, CRED, Zoho, Freshworks, Chargebee, Rocketlane, Postman, BrowserStack, InMobi, Media.net, Groww, Slice, Dream11, MakeMyTrip, Ola, Urban Company, Delhivery, Cars24
AWS and Beyond
Build it in your own AWS account, break it on purpose, then fix it.
- Services
- 37
- Lab guides
- 52
- Total time
- ~265h
Data Structures & Algorithms
Step through every problem as a simulation, then write the code.
- Pattern guides
- 98
- Problems
- 469
SQL Mastery with Postgres
Real Postgres in the page. Write the query, then read the plan.
- Chapters
- 13
- Practice problems
- 44
- Total time
- ~23h
Coming soonSystem DesignAPI Design
Value additions
The content is only half the product.
The rest is how quickly you can move from an explanation to a mental model you can use.
Learn the patterns, not four thousand problems.
The usual way
- Hours of YouTube, pausing to copy notes and fighting to stay awake
- Random picks from LeetCode's 4,000+ problems, hoping one comes up
Here
We learn best by seeing, and a simulation needs your attention where an hour of video lets it drift. The course is laid out as 98 patterns and 469 problems, each with its own step-through simulation. Solve a handful under each pattern and you stop meeting new problems cold: you know which pattern to reach for.
- topics
- 16
- pattern guides
- 98
- problems with step-through simulations
- 469
4,000+problems on LeetCode, met at random
98 patterns469 problems under them, each with its own step-through
Reviews
Be one of the first reviewers.
Worked through a lab or a problem? Tell the next learner what it was like, what clicked and what did not.
Pricing
One payment. No renewal clock.
Every current course, plus anything published while your membership is active.
Membership Plus
All course content
₹1,500for 1 year
₹125 a month
- Data Structures & Algorithms16 topics · 98 pattern guides · 469 problems with step-through simulations
- AWS and Beyond37 services · 52 lab guides · ~265h lab time
- System Design6 parts · 92 lessons · 28 problems and teardowns
- SQL Mastery with Postgres13 chapters · 10 guided query labs · 44 practice problems
Membership Pro
RecommendedAll content, plus hands-on tools
₹2,500for 1 year
₹208 a month
Everything in Plus, and:
Data Structures & Algorithms
- A code editor beside every problem
- Run against the real test cases
- Saved attempts per problem
SQL Mastery with Postgres
- A live console and psql in every lab
- A playground beside every article