Master Python list comprehensions, dict/set comprehensions, generator expressions — syntax, nested comprehensions, and when to use each.
Master PHP exception handling — try-catch-finally, custom exception classes, global error handlers, and production-safe error logging.
Master ES6+ JavaScript features — destructuring, spread/rest, optional chaining, nullish coalescing, template literals used in every modern codebase.
Understand hash tables from scratch — hash functions, chaining vs open addressing, load factor, and solving Two Sum, Group Anagrams with Python.
Master Laravel Eloquent — all relationship types, solving the N+1 query problem with eager loading, scopes, mutators and advanced query builder.
Master Python context managers — __enter__ __exit__, contextlib.contextmanager, ExitStack, and real-world uses for file handling, DB connections and timing.
