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// Engineering notes
Practical guides, deep dives, and cheat sheets on the tools and formats we use every day.
DevSpeedTools is more than a collection of converters and formatters. This blog covers the engineering decisions, format specifications, and developer workflows behind the tools. Whether you're debugging a YAML indentation issue, choosing between JSON and YAML for a new project, or trying to understand JWT token structure, you'll find actionable answers here. Every post is written by developers for developers — no fluff, no filler, just practical knowledge you can use immediately.
Engineering · Sep 22, 2026
Unix timestamps look like a single integer until a unit mismatch turns today into 1970. Epoch seconds vs milliseconds, ISO 8601, time zones, and a conversion cheat sheet for the classic bugs.
Engineering · Sep 23, 2026
A regex that passes the example in your head can still fail on real input. A practical workflow for testing patterns in the browser: flags, capture groups, catastrophic backtracking, and readable patterns.
Data Formats · Sep 17, 2026
How to convert CSV data to JSON, when to use each format, and the common pitfalls that trip up developers working with delimited data.
Data Validation · Sep 18, 2026
What JSON Schema is, how to validate data against a schema, common patterns, and how to debug invalid JSON.
Data Formats · Sep 19, 2026
A comparison of YAML and TOML for configuration files. Syntax differences, use cases, and when to prefer one over the other.
Encoding · Sep 14, 2026
Encode and decode Base64 strings instantly in your browser. UTF-8 support, URL-safe Base64, JWT decoding — all processing happens locally.
Security · Sep 14, 2026
Paste a JWT token and decode it instantly in your browser. See the header, payload, expiration, and all claims — no server upload, no risk.
Formatting · Sep 14, 2026
Format, beautify, and minify JSON online with zero upload. A free JSON formatter that runs entirely in your browser, with customizable indentation and instant results.
Engineering · Sep 14, 2026
Generate UUID v4 (random) and UUID v7 (time-ordered) instantly in your browser. Bulk generation, copy to clipboard, no upload required.
Engineering · Sep 11, 2026
The HTTP 419 status code isn't an official IANA code. Here's where it comes from, why you're seeing it, and how to resolve it in your application.
Security · Sep 9, 2026
Plaintext passwords in a database are a breach waiting to happen. Here's what modern password storage looks like, why 'just hash it with SHA-256' isn't enough, and what to do instead.
Security · Sep 7, 2026
HTML entities turn special characters into safe sequences. They prevent XSS, preserve content integrity, and trip up every developer at least once. Here's the full picture.
Encoding · Sep 5, 2026
URL encoding turns unsafe characters into percent-encoded sequences. It's simple until it isn't — double encoding, query parameters vs paths, and the one rule that prevents 90% of bugs.
Formatting · Sep 3, 2026
Tabs vs spaces, trailing commas, sorted keys, compact vs pretty — every JSON formatting decision has a trade-off. Here's what actually matters.
Encoding · Sep 1, 2026
Base64 turns binary data into safe ASCII text. It's everywhere — emails, JWTs, data URIs, embeddings — but it's not encryption. Here's how it works and where developers actually need it.
Engineering · Aug 28, 2026
Client-side processing means your data never leaves your browser — better privacy, lower infra costs, and faster tools. Here's the trade-off and how the best dev tools handle it.
Security · Aug 28, 2026
Most online JWT decoders send your token to a third party. Here's why that matters, and how to inspect a JWT locally with the same ease.
Engineering · Aug 28, 2026
UUID v7 is the new default for database primary keys, but v4 is still the right choice for security tokens. Here's how to pick, with a side-by-side comparison and benchmarks.
Engineering · Aug 28, 2026
The browser is a serious runtime now. View Transitions, the Popover API, WebGPU compute, and the File System Access API have all matured. Here's what they unlock and how to use them.
Data formats · Aug 28, 2026
YAML anchors (&) and aliases (*) let you reuse config without copy-paste. Here's how they work, when to use them, and the gotchas that bite people in production.
Data formats · Aug 28, 2026
YAML and JSON look interchangeable on the surface, but they optimise for different audiences. Here's how to pick the right format for config files, APIs, CI pipelines, and Kubernetes manifests.
Engineering · Aug 24, 2026
Every minute, every weekday at 9am, first of the month, last Friday — copy-paste cron expressions with explanations of what every field does.
The DevSpeedTools blog covers three main areas: data formats and serialization (YAML, JSON, TOML, CSV), developer tooling (converters, formatters, validators, encoders), and software engineering best practices (security, performance, API design). Every post is tied to a practical problem developers face daily.
We write for developers who want quick, actionable answers — not ten-page SEO articles that bury the answer at the bottom. Each post starts with the answer, explains the why, and links to the relevant tool so you can try it immediately.
Every post is written by the DevSpeedTools team — developers who build and maintain the tools on this site. We write about problems we've actually solved, formats we've actually debugged, and workflows we've actually used. No ghostwriters, no AI-generated filler, no recycled content from other blogs.
If you find a post useful, try the linked tool — it was built to solve the exact problem the post describes. If you have a suggestion for a topic you'd like us to cover, reach out through our contact page.
// Stay updated
We regularly add new tools and write new posts covering developer workflows, data format conversions, and engineering best practices. Bookmark DevSpeedTools and check back for new content, or use the search shortcut (⌘ K) to find what you need instantly.