The four groups
Markup / data-serialization formats
JSON · YAML · TOML · XML
Things vanilla JSON doesn't allow
COMMENTS · TRAILING COMMAS · SINGLE QUOTES · UNDEFINED
Values JS `typeof` can return
NUMBER · STRING · BOOLEAN · SYMBOL
Words paired with TYPE
PRIMITIVE · ANY · GENERIC · BLOOD
Why this puzzle works
The TS group is loaded with red herrings: ANY and GENERIC are both TypeScript modifiers but here they're in the wordplay group (any-type, generic-type). PRIMITIVE is the cleanest tell — 'primitive type' is the wordplay; the actual primitive types (number/string/boolean/symbol) are in blue. BLOOD is the cherry on top that confirms purple is a wordplay group and not a 'TS type modifier' group.
How to read a Connectle without solving it
A code-themed grouping puzzle rewards counting as much as recognition. Start by listing every plausible group, then notice which tiles appear in two lists. Whichever group has exactly four unambiguous members is your anchor — solve it first and the rest of the board collapses by elimination. The hardest tier (purple) is almost always wordplay: tiles that share a prefix or suffix, not a concept. If a tile feels orphaned, ask whether the same word could follow or precede a common engineering word like root, stack, cache, or queue.