Language
SQL
A declarative, set-based language. Indexes, transactions and joins are the real skill — not the ORM.
SQL describes the result, not the loop. That is the particularity seniors forget when they chain Doctrine queries in PHP. N+1, missing indexes and SELECT * are language misuse, not “MySQL being slow”.
ACID transactions, isolation levels, and explain plans are part of the language’s contract. JSON columns and CTEs exist; they do not replace a model.
PHP talks to SQL through PDO or an ORM. A senior still reads the generated query. Ibexa’s repository is one store; business tables are another. Both are SQL.