Developer Tools
Developer Tool Guides
This is the reference shelf for the utilities that sit between your editor and your terminal. Cron gets the most attention, because its five fields hide genuine traps: step values that do not divide sixty, the OR rule that applies when both day fields are restricted, and the daylight saving transition that deletes 2 AM once a year. UUIDs get a version-by-version breakdown — why v4 is random, why v7 is time-ordered and index-friendly, and when a database sequence is still the better key. Hashing guides separate the fast checksums from the cryptographic digests and from the deliberately slow password hashes, because using the wrong one is a security bug rather than a performance choice. Regular expressions, diffing, encoding and token inspection round out the set, each written around the situation that sends you looking for the tool.
8 guides in this topic · All posts
JSON Crack Alternative Without Signup: Viewing JSON as a Tree
JSON Crack draws JSON as a node graph. If you want a collapsible tree with path queries instead, here is how the two compare — checked September 2026.
5 min read · Updated 2026-09-18FreeFormatter Alternatives (2026): Where Its Tools Went
FreeFormatter.com has been retired and its tool pages now return 404. A verified map of where each formatter, validator, escaper and encoder moved.
6 min read · Updated 2026-09-11Escaping vs Parameterised Queries
Why escaping quotes does not stop SQL injection: numeric contexts, LIKE, identifiers, second-order attacks, and how prepared statements close the hole.
8 min read · Updated 2026-09-11How to Escape a Single Quote in SQL
How to escape a single quote in SQL: the ANSI doubling rule, MySQL backslashes, Postgres dollar quoting, Oracle q-strings, LIKE patterns and binding.
9 min read · Updated 2026-09-11SHA-256 vs MD5 vs HMAC: How Hashing Works and Which One to Use
What a cryptographic hash guarantees, why MD5 and SHA-1 are broken but fine for checksums, how HMAC differs from a hash, and why passwords need Argon2.
6 min read · Updated 2026-09-10UUID v4 vs UUID v7: Which Should You Use for Database Keys?
UUID v4 and v7 compared: why random v4 keys fragment B-tree indexes, how v7's timestamp fixes it, the collision math, and how to generate and store both.
7 min read · Updated 2026-09-10Cron Expression Syntax Explained: Fields, Special Characters and Real Schedules
Cron syntax field by field: ranges, the * , - / characters, the day-of-month OR day-of-week rule, DST pitfalls, and Quartz's six-field variant.
6 min read · Updated 2026-09-18Regular Expressions Explained: A Practical Cheat Sheet With Tested Examples
A practical regex cheat sheet: metacharacters, quantifiers, groups, lookarounds and JavaScript flags, with tested patterns for emails, dates and slugs.
7 min read · Updated 2026-09-10