Developer Guides
In-depth technical guides on JSON, regular expressions, Git diffs, JWT tokens, and more — written for working software engineers.
How QR Codes Actually Work: The Engineering Behind the Squares
QR codes are one of the most-scanned technologies in the world but almost nobody understands their structure. Finder patterns, Reed-Solomon error correction, and data encoding modes explained.
QR Codes Were Invented to Track Car Parts — Now They Track Everything
QR codes were invented in 1994 at a Toyota subsidiary. They sat in obscurity for a decade, then exploded globally during COVID. The full story of an open-standard triumph.
Dynamic vs Static QR Codes: The Difference Nobody Explains Clearly
Static QR codes encode data directly — permanent, private, free. Dynamic codes encode a redirect — updatable, trackable, and dependent on a third-party service. Here is when to use each.
QR Codes for Business: What Works, What's a Gimmick, and What's a Liability
The post-COVID QR code boom produced genuine use cases and a lot of misuse. QR codes on websites, billboard QR codes at highway speed, and the real security risks of unmonitored physical codes.
Designing QR Codes That Actually Scan: The Engineering Constraints You're Ignoring
Every designer who puts a logo in the center of a QR code is spending error correction budget they didn't know they had. QR code design is constrained engineering, not free art.
QR Code Phishing Is the Fastest-Growing Attack Vector You're Ignoring
QR code phishing (quishing) grew 587% since 2022. Physical placement creates implicit trust, URLs are hidden before scanning, and most email security tools cannot detect it.
The WiFi QR Code: How It Works and Why You Should Generate One Today
A WiFi QR code eliminates the 'what's the password?' interaction entirely. iOS and Android support it natively. Here is the format, where to deploy it, and the security considerations.
QR Code Menus: The Data on Whether They Actually Work
QR menus were forced on restaurants by COVID and retained for cost savings. But customer preference data is clear, accessibility problems are real, and the right implementation is nuanced.
QR Code Error Correction: The Engineering Safety Net You Didn't Know You Had
QR codes use Reed-Solomon error correction — the same mathematics that makes CDs play through scratches and enables deep-space communication. Here is how it works and when to use each level.
vCard QR Codes Are the Business Card of the Future — If You Do Them Right
A vCard QR code lets people scan your business card and instantly save your contact with no app required. Here is the format, size limits, and why proprietary digital card startups keep failing.