SEN LLC - DEV Community

SEN LLC

Apr 15

Envelope Encryption for .env Files, the Right Way (PHP CLI, Stdlib Only)

#php #cli #security #tutorial

9 min read

SEN LLC

Apr 15

Mocking an OpenAPI Spec From Scratch in 600 Lines of TypeScript

#typescript #hono #openapi #tutorial

9 min read

SEN LLC

Apr 15

Parsing RSS and Atom From Scratch in Rust with quick-xml

#rust #axum #rss #tutorial

10 min read

SEN LLC

Apr 15

The Four Pagination Strategies Every Backend Dev Should Know

#php #slim #api #tutorial

9 min read

SEN LLC

Apr 15

zod-to-schema: A Zero-Config CLI That Runs Your TypeScript In-Process

#typescript #zod #jsonschema #tutorial

8 min read

SEN LLC

Apr 15

A local requestbin in 200 lines of PHP — why self-hosting beats webhook.site for production debugging

#php #slim #webhooks #tutorial

9 min read

SEN LLC

Apr 15

The `notify` crate is surprisingly pleasant — I built a cross-platform file watcher in four dependencies

#rust #cli #developertools #tutorial

8 min read

SEN LLC

Apr 15

SSE Is the Right Answer More Often Than You Think — A Hono + TypeScript Reference Service

#typescript #hono #sse #tutorial

9 min read

SEN LLC

Apr 15

Parsing phpinfo() in Pure PHP — or, How to Diff Two Containers

#php #cli #devops #tutorial

8 min read

SEN LLC

Apr 15

gron Was Right: Flat JSON Is Easier to Grep (A Rust Take With Four Formats and a Round-Trip)

#rust #cli #json #tutorial

10 min read

SEN LLC

Apr 15

HTTP Cookies in the Wild Are a Mess — I Built a CLI That Eats Them

#typescript #node #cookies #tutorial

8 min read

SEN LLC

Apr 15

Password Generation Is About Entropy, Not Randomness

#rust #cli #security #tutorial

8 min read

SEN LLC

Apr 15

HMAC Webhook Signing Isn't Complicated — the Formats Are

#typescript #node #webhooks #tutorial

8 min read

SEN LLC

Apr 15

A Minimal HTTP Debug Server in Rust with axum

#rust #axum #debugging #tutorial

10 min read

SEN LLC

Apr 15

I Wrote a JWT Verifier in 150 Lines. You Probably Shouldn't — But Here's What I Learned.

#typescript #node #jwt #tutorial

1

9 min read

SEN LLC

Apr 15

hexview: writing a color-aware hex dump in Rust with one dependency

#rust #cli #tutorial #binary

9 min read

SEN LLC

Apr 15

A TypeScript API Starter With Sharp Boundaries — Hono + Zod + better-sqlite3

#typescript #hono #node #tutorial

8 min read

SEN LLC

Apr 15

Writing a Safe SQL INSERT Generator Taught Me Why ORMs Exist

#php #sql #cli #tutorial

7 min read

SEN LLC

Apr 15

RFC 5545 is a 200-Page Spec. Your iCalendar Feed Needs About 150 Lines.

#php #slim #ical #tutorial

9 min read

SEN LLC

Apr 15

PHP as a Microservice: A Markdown-to-HTML API in 200 Lines of Slim 4

#php #slim #markdown #tutorial

8 min read

SEN LLC

Apr 15

Read composer.lock Directly: A 1000-Line CLI That Beats composer show --tree

#php #composer #cli #tutorial

8 min read

SEN LLC

Apr 15

Why a Tiny Audit Tool Beats a Big Security Framework (laravel-audit)

#php #laravel #security #tutorial

9 min read

SEN LLC

Apr 15

What's Actually In This CSV? A Zero-Dep Python Profiler

#python #cli #csv #tutorial

9 min read

SEN LLC

Apr 15

Perceptual Image Diff Without NumPy — Building a Pillow-Only CLI

#python #cli #imageprocessing #tutorial

9 min read

SEN LLC

Apr 15

When the Library IS the Product: A 200-Line FastAPI Wrapper for wordcloud

#python #fastapi #imageprocessing #tutorial

8 min read

SEN LLC

Apr 15

Building a Furigana HTTP Service in Python: Why It's Not Just a Lookup Table

#python #fastapi #japanese #tutorial

6 min read

SEN LLC

Apr 15

Japanese Width Conversion Without Regex: Full↔Half ASCII, Katakana, and the Dakuten Merge Problem

#python #japanese #cli #tutorial

9 min read

SEN LLC

Apr 15

Slugifying Japanese URLs Is Harder Than You Think — I Built a Focused CLI

#python #japanese #cli #tutorial

10 min read

SEN LLC

Apr 15

Every Link Preview in Your App Is the Same 30 Lines You Haven't Written Yet

#python #cli #opengraph #tutorial

7 min read

SEN LLC

Apr 15

Generating a Valid RSS Feed From Scratch in Stdlib Python

#python #cli #rss #tutorial

10 min read

SEN LLC

Apr 15

Counting Moras: Why Your 5-7-5 Haiku Validator is Probably Wrong

#python #japanese #cli #tutorial

9 min read

SEN LLC

Apr 15

Text Generation Before Transformers: Building a Markov Chain in 200 Lines of Python

#python #cli #nlp #tutorial

10 min read

SEN LLC

Apr 15

Writing `tail -f | jq` That Doesn't Feel Like a Rube Goldberg Machine

#python #cli #logging #tutorial

10 min read

SEN LLC

Apr 15

Building a Hash Identifier Without ML — Just Rules, Scores, and Honesty About Ambiguity

#python #cli #security #tutorial

8 min read

SEN LLC

Apr 15

How ULID Actually Works: Implementing the Codec in 60 Lines of Python

#python #cli #ulid #tutorial

10 min read

SEN LLC

Apr 15

A 150-Line FastAPI Service for 'Is Today a Holiday?'

#python #fastapi #calendar #tutorial

8 min read

SEN LLC

Apr 15

When does this cron run next? Give it its own 70 MB container

#python #fastapi #cron #tutorial

8 min read

SEN LLC

Apr 15

How to Make Sense of a HAR File Without DevTools

#python #performance #cli #tutorial

8 min read

SEN LLC

Apr 15

Python's urllib.robotparser Is Subtly Wrong — and Why That Matters for SEO

#python #seo #cli #tutorial

8 min read

SEN LLC

Apr 15

Writing a Polite Crawler: sitemap-gen for the Sites SSGs Forgot

#python #seo #cli #tutorial

9 min read

SEN LLC

Apr 15

What's actually in a modern favicon set (and why everyone gets it wrong)

#python #cli #favicon #tutorial

1

10 min read

SEN LLC

Apr 15

I Built a FastAPI QR Code Service and the Library Choice Mattered More Than the Code

#python #fastapi #qrcode #tutorial

9 min read

SEN LLC

Apr 15

The Right-Sized Image Service: A FastAPI Watermarker in ~110 MB

#python #fastapi #imageprocessing #tutorial

10 min read

SEN LLC

Apr 15

grep's flat output is the wrong abstraction for exploratory searches

#python #cli #grep #tutorial

9 min read

SEN LLC

Apr 15

Dead Code in Python Is Undecidable — So I Built a Detector That Admits It

#python #staticanalysis #cli #tutorial

10 min read

SEN LLC

Apr 15

Building linkcheck: Why I Stopped Parsing Markdown with Regex

#python #cli #markdown #tutorial

9 min read

SEN LLC

Apr 15

Writing a Privacy Tool You Can Actually Trust: exif-stripper in 500 Lines of Python

#python #privacy #cli #tutorial

8 min read

SEN LLC

Apr 15

A 60 MB FastAPI Service That Extracts Text From PDFs (and Why It Beats Tika for the 90% Case)

#python #fastapi #api #tutorial

8 min read

SEN LLC

Apr 15

Stop Using `diff` on CSV Files — Build a Semantic CSV Diff in 200 Lines of Python

#python #cli #csv #tutorial

9 min read

SEN LLC

Apr 15

Your .env.example Is Not a Schema. Here's a 400-Line Python CLI That Fixes That

#python #devops #cli #tutorial

9 min read

SEN LLC

Apr 15

I Built a jq Alternative That Speaks JSONPath — and Deliberately Wrote Almost No Parser Code

#python #cli #json #tutorial

9 min read

SEN LLC

Apr 15

Same Game in Vanilla JS — Flood Fill, Gravity, and Column Compression

#javascript #gamedev #puzzle #algorithms

4 min read

SEN LLC

Apr 15

100 Projects in 4 Days — A Meta-Dashboard Celebrating the Milestone

#javascript #portfolio #milestone #meta

3 min read

SEN LLC

Apr 15

A Memory Card Matching Game With CSS 3D Flip and Immutable State

#javascript #gamedev #css #immutable

3 min read

SEN LLC

Apr 15

A Loan Calculator With 元利均等 vs 元金均等 and Prepayment Simulation

#javascript #finance #calculator #math

3 min read

SEN LLC

Apr 15

An International Tip Calculator — Because Tipping Customs Are Wildly Different

#javascript #calculator #internationalization #culture

3 min read

SEN LLC

Apr 15

An IPv4 Subnet Calculator With Binary Visualization and /31 Handling

#javascript #networking #tools #webdev

3 min read

SEN LLC

Apr 15

Cron Expression to Natural Language — In English and Japanese

#javascript #cron #parser #webdev

3 min read

SEN LLC

Apr 15

A YAML ↔ JSON Converter With a Handwritten YAML Subset Parser

#javascript #yaml #json #parser

3 min read

SEN LLC

Apr 15

A Countdown Tracker That Handles DST, Timezones, and Calendar-Day Math Correctly

#javascript #date #webdev #productivity

3 min read

Writing Debut