📚Karuvigal Blog
Developer guides & tutorials
Recent Articles
Cron Expression Internals: How Operating Systems Schedule Jobs and Where Developers Go Wrong
A deep technical dive into how cron parses and executes scheduled jobs, covering Unix history, DST traps, Quartz extensions, thundering herd problems, and systemd timer alternatives.
Linux Permissions Internals: Octal Modes, SUID, and Advanced ACLs
Go beyond chmod 777. Learn how the Linux kernel evaluates permissions bitwise, the security implications of SUID/SGID, Sticky bits, and how Access Control Lists override standard modes.
TypeScript Compiler Internals: From AST to Type Erasure
A deep technical look into the TypeScript compiler (tsc). Understand the parsing phase, Abstract Syntax Trees (AST), structural typing, and why type erasure means your types don't exist at runtime.
How to Secure Your API Endpoints Using Custom JWT Payload Claims
A deep technical dive into JWT anatomy, custom claims for RBAC, claim validation pitfalls, and mitigating common vulnerabilities like the 'none' algorithm.
Cryptographic Hash Functions: SHA-256, SHA-3, BLAKE3 and When to Use Which
A comprehensive technical comparison of modern cryptographic hash functions. Understand the mathematical constructions behind SHA-2, SHA-3, and BLAKE3, and learn exactly which algorithm to choose.
Base64 Encoding Internals: Bit Shifting, Padding, and the Data URI Scheme
A deep dive into the mechanics of Base64. Understand how 3 bytes of binary data become 4 printable ASCII characters, the mathematical necessity of the equals sign (=) for padding, and Base64URL variants.
CSV to JSON Transformation Patterns: Nested Objects, Type Coercion, and Schema Inference at Scale
A deep technical guide to the CSV-to-JSON transformation problem. Learn type inference algorithms, dot-notation nesting, large file streaming strategies, and encoding edge cases.
A Deep Dive into V8 JavaScript Memory Isolation for Browser-Based Developer Tools
Explore the inner workings of the V8 JavaScript engine. Understand heap architecture, cross-origin isolation, and how client-side tools leverage WeakRefs to prevent memory leaks in the browser.
URL Encoding Internals: RFC 3986, Unicode, and the Base64 Connection
A deep dive into percent-encoding. Understand the history of URI characters, how UTF-8 bytes are encoded, why encodeURIComponent differs from encodeURI, and how XSS attacks exploit decoding layers.
JSON vs XML vs YAML: A Technical Guide to Data Serialization
A deep dive into the syntax, performance, and use cases of the three major data serialization formats. Understand when to use JSON, XML, or YAML in your architecture.
Karuvigal vs. Beautifier.io: The Shift to Local Data Processing
A technical comparison of code formatting approaches. Discover why modern development demands client-side processing over cloud-based formatting services.
Karuvigal vs. Legacy Utility Sites: The Future of Developer Tools
Why the era of ad-ridden, slow, and privacy-invasive online utility websites is ending, and how Karuvigal is pioneering a new standard for professional developer tools.
The Mathematics of Barcodes: How EAN-13 and Code 128 Work
A technical deep dive into the encoding algorithms, check digit calculations, and mathematical principles that make 1D barcodes the backbone of global logistics.
QR Code Error Correction: The Math Behind the Magic
Ever wonder how a QR code still works when half of it is torn or covered by a logo? Explore the Reed-Solomon error correction algorithm that makes 2D barcodes indestructible.
Deep Dive into UUID Versions: When to Use v1, v4, or v7
A technical guide to Universally Unique Identifiers (UUIDs). Understand the underlying algorithms, collision probabilities, and why UUIDv7 is the new standard for database primary keys.
2D Barcode Standards: Why QR Codes Won the Format War
QR codes dominate the 2D barcode landscape, but they aren't the only standard. Explore the technical differences between QR, Data Matrix, PDF417, and Aztec codes.
Karuvigal vs. ME-QR: Why Developers and Marketers Need Truly Free QR Codes
A detailed comparison between Karuvigal's completely free, offline-first QR Code Studio and cloud-based services like ME-QR. Learn why client-side generation is safer and more reliable.
Secure Password Storage: Salting, Hashing, and Key Derivation
Storing passwords in plain text is a cardinal sin of backend engineering. Learn the modern standards for secure password storage using bcrypt, Argon2, and cryptographic salting.
Optimizing JSON APIs: Compression, Pagination, and Parsing
A deep dive into strategies for optimizing large JSON API payloads. Learn how to implement gzip, streaming parsers, and cursor-based pagination for high-performance applications.
Karuvigal vs. 10 Minute Mail: Why Professionals Need Advanced Temporary Email
A deep dive into why developers and QA engineers are switching from basic 10 Minute Mail services to Karuvigal's professional temporary email infrastructure.
Client-Side Security: Leveraging the Web Crypto API
How modern browsers achieve military-grade encryption offline. Learn how Karuvigal uses the Web Crypto API to hash passwords and generate UUIDs securely without sending data to a server.
The Era of Offline-First Developer Tools
Why relying on cloud connectivity for basic developer utilities is a broken model. Explore the architecture of Progressive Web Apps (PWAs) and local-first execution.
The Science of Password Entropy: Why Length Beats Complexity
A mathematical breakdown of password strength. Understand why a long string of simple words is exponentially harder to crack than a short, complex password with special characters.
JSON Formatting: The Complete Developer Guide
Master JSON formatting with our comprehensive guide. Learn best practices, syntax rules, common mistakes, and advanced techniques for working with JSON data in 2025.