Master Coding Skills &
System Design.

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 SQL subqueries — scalar, column, table, and correlated subqueries. EXISTS vs IN performance, and when to use CTEs instead.

Master ES6+ JavaScript features — destructuring, spread/rest, optional chaining, nullish coalescing, template literals used in every modern codebase.

Design a distributed rate limiter — token bucket vs sliding window, Redis-backed implementation, API middleware, and handling distributed deployments.

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.

Understand JavaScript prototype chain, constructor functions, ES6 classes, and how inheritance works under the hood with clear examples.