Tils - Things I learned

November 25, 2025 | 03:35 PM

Ever wondered what a file looked like years ago? Here’s a simple Git trick to view old file versions instantly, without touching your current state.

November 01, 2025 | 02:35 PM

Message queues let different services communicate reliably and asynchronously, acting as a buffer between producers and consumers. They’re essential for distributed systems, ensuring events like video uploads or analytics are handled efficiently and without blocking processes.

October 29, 2025 | 11:07 PM

Git stores your repository as a content-addressable system using just four object types: blobs for files, trees for directories, commits for snapshots, and tags as named references. Together, these objects form a directed acyclic graph, letting Git track changes efficiently while you work on your project.

October 19, 2025 | 07:00 PM

The Linux kernel uses procfs, a virtual filesystem at /proc, to manage and expose information about all running processes and system state. It provides a lightweight, text-based interface in RAM that lets you inspect everything from CPU and memory stats to per-process details like command-line arguments, environment variables, and thread info—making process management and monitoring simple and efficient.

August 06, 2025 | 05:00 PM

Copy constructors define how an object is created from another object of the same class, while the assignment operator controls how values are copied between already-initialized objects. This distinction matters in C++ because initialization and assignment are handled by different mechanisms, even though they look similar in code.

March 18, 2025 | 03:00 PM

An efficient way to think about pairwise bitwise AND by reframing the problem in terms of bit positions instead of element pairs. Using a running bitmask, this approach reduces a quadratic check to a linear scan while building intuition around AND and OR operations.

February 11, 2025 | 05:00 PM

A practical breakdown of how Linux file permissions actually work, from symbolic flags like rwx to numeric modes like 400 and 755. Useful for understanding why commands like chmod 400 key.pem matter and how Linux enforces security at the filesystem level.

February 10, 2025 | 05:00 PM

A concise introduction to load balancing and why it matters in distributed systems. It explains how traffic skew can overload individual servers, how a load balancer smooths this out, and the practical benefits around availability, scalability, security, and performance, along with a high-level view of common load-balancing algorithms.

February 07, 2025 | 10:20 AM

A light, practical note on using the ping command to discover a website’s IP address. It touches on what ping actually does at the network level and shows how a simple diagnostic tool can double as a quick way to reason about host availability and connectivity.

February 07, 2025 | 10:00 AM

A quick, hands-on note on what an IP address is and how to find your own machine’s IPv4 and IPv6 addresses from the terminal. Useful when testing networking or socket programs and a good excuse to get comfortable with basic Unix commands like ifconfig, pipes, and grep.

February 05, 2025 | 12:00 PM

A short note on the self-serving bias: how we tend to credit our successes to skill and effort, while conveniently outsourcing failures to external circumstances. Understanding this bias is useful for more honest self-evaluation, better learning from mistakes, and clearer judgment of both wins and losses.

February 05, 2025 | 05:00 AM

A walk-through of searching in a bitonic array, including a common mistake and why it fails. The key insight is breaking the problem into finding the peak first, then applying binary search on both halves to get a clean O(log N) solution.

February 01, 2025 | 05:00 PM

A straightforward, step-by-step note on SSH’ing into an AWS EC2 instance using a key pair. It covers why file permissions matter for .pem keys, how to connect using either a public IPv4 address or DNS, and serves as a practical reference for getting terminal access to a remote Ubuntu server.

January 31, 2025 | 10:00 AM

A set of beginner-friendly notes on how the Internet is structured and how computers communicate. It breaks down core networking concepts like hosts, packets, routes, ISPs, and protocols using simple language and everyday analogies, building intuition before formal definitions from standard networking literature.