Tech Blog
We share insights gained on the software development front line, including web development, algorithms, and performance optimization.
What Is URL Encoding? Percent-Encoding Explained
Reserved vs. unreserved characters, how percent-encoding works (UTF-8 byte by byte), and the difference between encodeURI and encodeURIComponent.
Read more →What Is Unix Time? Epoch Seconds, Time Zones, and Year 2038
What epoch seconds are, seconds vs. milliseconds, time zones and UTC, leap seconds, and the Year 2038 problem.
Read more →What Is a Hash Function? SHA-256, Use Cases, and Why It's Not Encryption
The one-way nature of hash functions, how they differ from encryption, SHA-256 use cases, and how to store passwords correctly (salting/stretching).
Read more →How Diff Works — Finding Changes with Longest Common Subsequence
How diff finds changes between two texts, explained through the Longest Common Subsequence and dynamic programming with worked examples.
Read more →What Is a JWT? Structure, Signatures, and Use Cases
The three parts of a JWT, registered claims, HMAC and public-key signatures, why the payload is not encrypted, and security pitfalls.
Read more →HTML Escaping and XSS — Why You Must Encode Special Characters
Why HTML escaping matters, how cross-site scripting (XSS) works and its types, and context-aware output defenses.
Read more →Naming Conventions and Case Styles — camelCase, snake_case, kebab-case, PascalCase
The differences between camelCase, snake_case, kebab-case and PascalCase, language conventions, and how to stay consistent.
Read more →Binary and Hexadecimal Explained — How Computers Represent Numbers
How binary and hexadecimal work, why computers use them, and how to convert to and from decimal, with a 0-15 table and examples.
Read more →What Is Lorem Ipsum? Origin and How to Use Placeholder Text
The origin of the meaningless placeholder text 'Lorem ipsum', why it is used in design, and what to watch out for.
Read more →Regular Expressions for Beginners — Common Patterns and Syntax
The building blocks of regular expressions — character classes, quantifiers, groups, anchors and flags — with practical examples for email, URLs and dates.
Read more →CSV vs JSON — Differences and How to Convert Between Them
The differences between CSV and JSON (nesting, types, size, use cases) and key points for converting between them, with a comparison table.
Read more →Text Processing Tips — Master Dedupe, Sort, and Trim
Tips for everyday text wrangling — sorting (lexicographic vs. numeric), removing duplicates, trimming blanks — alongside command-line equivalents.
Read more →What Is a UUID? How v4 Works, Collision Probability, and When to Use It
The notation of the 128-bit UUID and its versions (v1/v4/v5/v7), the random structure of v4, collision probability from the birthday problem, and where to use it in distributed systems — explained in line with the RFCs. Includes a link to the generator tool.
Read more →Color Codes Explained — HEX vs RGB vs HSL and How to Convert
The differences between HEX, RGB and HSL for color on the web, with step-by-step conversion algorithms and worked examples — 3-digit HEX and alpha, why HSL is intuitive, and contrast basics. Includes a link to the converter tool.
Read more →Counting Characters and UTF-8 — Characters, Bytes, and Graphemes
Why a "character count" changes with how you count — explained through Unicode code points, UTF-8 byte length, JS string length (UTF-16), and grapheme clusters, with worked examples for emoji and combining characters. Includes a link to the counter tool.
Read more →Subnetting and CIDR Basics — Understand IP Address Division from Scratch
From the 32-bit structure of IPv4 to subnet masks and prefix lengths (CIDR like /24), network and broadcast addresses, usable host counts, private addresses and IP classes, and worked subnetting examples — explained from the ground up. Includes a link to the calculator tool.
Read more →What Is JSON? Syntax, Data Types, Common Errors, and Formatting Tips
JSON's six data types and syntax rules, common errors such as trailing commas and single quotes, when to pretty-print vs. minify, and how validation works — explained in line with RFC 8259. Includes a link to the formatter/validator tool.
Read more →What Is Base64? How It Works, Use Cases, UTF-8 and URL-Safe Encoding
How three bytes map to four characters and padding, use cases like email and Data URLs, handling Japanese and emoji via UTF-8, and URL-safe Base64 (RFC 4648 §5). We also make clear it is not encryption, with a link to the converter tool.
Read more →QR Code Specifications Explained (with sample QR codes)
From versions (1–40) and module counts, data capacity, and the four encoding modes to error correction, structure, and masking. We explain the specification while looking at actual generated sample QR codes. Includes a link to the generator tool.
Read more →Barcode Specifications Explained (with sample barcodes)
We explain the characteristics and structure of EAN-13/JAN, EAN-8, UPC, CODE39, CODE128, ITF, and Codabar, along with how check digits work, using actual generated samples. Includes a link to the generator tool.
Read more →How Top Engineers Use Claude Code
We look at how leading engineers around the world—Armin Ronacher, Simon Willison, Mitchell Hashimoto, and Boris Cherny—actually use Claude Code, drawing on their original posts.
Read more →How Flask's Creator Armin Ronacher Uses Claude Code
claude-yolo with Docker, keeping logs in files, designing agent-friendly code, and CLI over MCP. We dig into the Flask creator's practices with quotes from the original article.
Read more →How Django Co-creator Simon Willison Uses Claude Code
The idea of "designing the agent loop," YOLO mode and sandboxes, throwaway $5 Fly.io orgs, and using tests as a means of verification—explained with quotes.
Read more →How Claude Code's Creator Boris Cherny Uses It
Running multiple Claudes in parallel, recording mistakes in CLAUDE.md, /commit-push-pr, moving from plan mode to auto mode, and "2–3x quality through verification"—with sources.
Read more →How Ghostty's Creator Mitchell Hashimoto Uses AI Agents
Delegating research, harness engineering (AGENTS.md), real examples and costs in Ghostty, and the cautionary idea of "agent psychosis"—explained with quotes from his own blog.
Read more →Running Projects with Claude Code
The Explore → Plan → Code → Commit loop, spec.md/plan.md, CLAUDE.md, git worktree, and TDD. We organize a repeatable workflow based on official docs and practitioners' blogs.
Read more →Building Test Scenarios with Claude Code
The verification loop, RED-GREEN-REFACTOR in TDD, E2E verification via browser automation, and cross-verification with sub-agents. We explain how to build a test strategy based on research from external blogs.
Read more →Team Collaboration with Claude Code
Sharing CLAUDE.md, committing the .claude/ directory, GitHub Actions integration, MCP servers (Slack/Linear), and onboarding. We introduce how to build the foundations for team collaboration.
Read more →Documentation Management with Claude Code
CLAUDE.md and automatic memory, initialization with /init, generating JSDoc/OpenAPI from code, and keeping docs in sync with hooks and CI. We explain how to keep documentation from going stale.
Read more →Understanding QR Code Error Correction Levels — Why They Still Scan When Dirty
We explain, in clear terms, how QR codes remain readable even when partly hidden by a logo or smudged, from the perspective of error correction levels (L/M/Q/H) and Reed-Solomon codes.
Read more →Intro to Sorting Algorithms — 7 Methods Chosen by Complexity
From bubble sort to quicksort and merge sort. We organize how the major sorting algorithms work and their time complexity (Big O notation), and explain how to choose the right one for the job.
Read more →Core Web Vitals: A Practical Guide — Improving Speed and Perceived Performance
Centered on the three metrics LCP, INP, and CLS, we summarize concrete measures to improve website load speed and user experience—from measurement to implementation, with a practical focus.
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