Exploring Tech, Finance & Productivity
Practical articles, free developer tools, and finance calculators. No jargon, no fluff.
Design a Key-Value Store (like DynamoDB) - System Design
A key-value store looks like a solved problem for about thirty seconds. “Put a value under a key, get it back later, it is a hash map.” Then …
Read MoreDesign a Metrics and Monitoring System - System Design
Everyone thinks a monitoring system is a database with a graph on top. “Every server writes its CPU and memory somewhere, you draw a line …
Read MoreSmall-Cap SIP: What 15-Year Rolling Returns Actually Show
A small-cap fund SIP page will show you one number: “18% CAGR since inception.” It will not show you that the same fund made you sit on a …
Read MoreDesign a Distributed Message Queue (like Kafka) - System Design
Everyone thinks a message queue is a list. “Producers push messages onto the back, consumers pop them off the front, done - it is a queue, …
Read MoreDesign YouTube / a Video Streaming Platform - System Design
A video platform looks trivial for about five seconds: POST /video to upload, GET /video to play. Then you remember that one uploaded file …
Read MoreDesign a Real-Time Leaderboard - System Design
Everyone thinks a leaderboard is a SELECT ... ORDER BY score DESC LIMIT 100. “Store the scores, sort them, return the top 100, done.” Then …
Read MoreDesign a Web Crawler - System Design
Everyone starts a web crawler the same way: a queue of URLs, a while loop, fetch, parse out the links, push them back on the queue, repeat. …
Read MoreDesign an Ad Click Aggregator - System Design
Everyone thinks an ad click aggregator is a SELECT COUNT(*) ... GROUP BY ad_id. “Log every click, count the rows, show the advertiser their …
Read MoreHow to Interview for an AI Engineer Role in 2026
If you prep for an AI engineer interview by grinding gradient descent derivations and softmax cross-entropy, you will walk in ready for a …
Read MoreTerm Insurance Cover: The Income-Replacement Math, Not a Round Number
“Take 1 crore cover.” It is the most repeated line in Indian personal finance, and it is a psychological number, not a financial one. One …
Read MoreDesign BookMyShow / a Ticket Booking System - System Design
“Design BookMyShow” looks like a catalogue app: list cities, list movies, list showtimes, take a payment, print a QR code. The interviewer …
Read MoreDesign Dropbox / a File Sync and Storage Service - System Design
A file sync service sounds like a glorified upload button until you count the bytes. The naive version is a single PUT /file that stores a …
Read MoreDesign Search Autocomplete / Typeahead - System Design
Everyone thinks autocomplete is a LIKE 'prefix%' query. “Index the search terms, run a prefix match, return the top ten, done.” Then the …
Read MoreEPF + VPF vs an Index Fund Over a 30-Year Career
The pitch for Voluntary Provident Fund is seductive and, for most of your salary, correct: 8.25% compounded, tax-free, government-backed, no …
Read MoreREITs vs InvITs in India - Where the Yield Actually Comes From
Most people buy a REIT or an InvIT because a screener showed a 6% or a 12% yield next to it, and 12% looks like a fixed deposit that quietly …
Read MoreDesign a Distributed Cache (like Redis) - System Design
Everyone thinks a cache is a hash map with a size cap. “Store key-value pairs in RAM, evict when it fills up, done.” Then the interviewer …
Read MoreDesign a Payment System / Digital Wallet - System Design
“Move 500 rupees from Alice to Bob” sounds like an UPDATE statement. Then you think about it. What if the request times out and the client …
Read MoreDesign Google Docs / Collaborative Editing - System Design
A document editor sounds trivial until you put two people in the same document. One editor is a text box that saves to a database: type, PUT …
Read MoreNPS at 60: The Annuity Reality Behind the 60% Lumpsum
Everyone sells NPS on the way in: the extra Rs 50,000 deduction under 80CCD(1B), the low-cost fund management, the equity exposure. Almost …
Read MorePostgres Is Still Eating Your Stack - The 2026 Extension Edition
Most “just use Postgres for everything” posts stop at the fun part. They show you that pgvector exists, that SKIP LOCKED gives you a queue, …
Read MoreDeveloper Tools
JSON Formatter
Format, validate & minify JSON instantly in your browser.
Open ToolJWT Decoder
Inspect JWT header, payload, and expiry without sharing tokens.
Open ToolProtobuf Encoder
Encode JSON to Protobuf binary or decode binary back to JSON.
Open ToolRegex Tester
Test regex patterns with real-time matching and group highlights.
Open ToolBase64 Encoder
Encode and decode Base64 strings with a single click.
Open ToolHash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes instantly.
Open ToolUUID Generator
Generate random v4 UUIDs. Copy with one click.
Open ToolUnix Timestamp
Convert between Unix timestamps and human-readable dates.
Open ToolFinance Calculators
SIP Calculator
Calculate monthly SIP growth with the power of compound interest.
EMI Calculator
Find your EMI for home loans, car loans, or personal loans.
1 Crore SIP
Figure out how much SIP you need to build 1 crore.
Emergency Fund
Calculate exactly how much emergency fund you should have.
HRA Calculator
Compute your tax exemption under Section 10(13A).
Investment Growth
Project your portfolio's future value with annual step-ups.
Want to practice coding? Browse 50 DSA problems with clean solutions.