Programming Tests: JavaScript, Python, Java, SQL & More

Pick your stack

Frameworks sit on top of the language they're written in. Take the language test first, then the framework.

WEBJavaScriptES6+, async/await, closures and the DOM.const x = await f();

React

Node.js

Angular

Vue.js

Take the JavaScript test

WEBTypeScriptTypes, generics, narrowing and declaration files.type Id = string | number;

Take the TypeScript test

WEBPHPModern PHP 8, OOP and common web patterns.$user?->name ?? 'guest';

Take the PHP test

DATA & BACK ENDPythonOOP, decorators, generators and Pythonic code.[x*x for x in nums]

Django

Take the Python test

DATA & BACK ENDSQLJoins, grouping, subqueries and window functions.GROUP BY team HAVING ...

Take the SQL test

DATA & BACK ENDJavaOOP, collections, streams and concurrency.list.stream().map(...)

Take the Java test

DATA & BACK ENDC#LINQ, async, generics and the .NET runtime.var q = from u in db...

Take the C# test

SYSTEMSGoGoroutines, channels, interfaces and errors.go worker(jobs)

Take the Go test

SYSTEMSRustOwnership, borrowing, traits and lifetimes.fn len(s: &str) -> usize

Take the Rust test

SYSTEMSC++Memory, templates, RAII and the STL.std::unique_ptr<T> p;

Take the C++ test

MOBILESwiftOptionals, protocols and SwiftUI basics.guard let u = user else

Take the Swift test

MOBILEKotlinNull safety, coroutines and data classes.val n = user?.name

Take the Kotlin test

Four kinds of question, in every test

OUTPUTPredict the output

print([1, 2] * 2)

What prints? Tests how well you know the language's rules, not just its syntax.

DEBUGSpot the bug

if (items.length = 0)

Find the line that breaks, and why.

IDIOMPick the idiomatic version

for i in range(len(xs)): print(xs[i])

Which of four working versions would a reviewer approve?

CONCEPTExplain the concept

async vs threads?

Short questions on how the runtime actually behaves.

Programming tests, explained

Where to start

Most used (2024)JavaScriptPythonSQL

Or simplyThe one you use most

For job-hunting, the most widely used languages open the most doors.

Knowledge vs coding

Knowledge testRules, idioms, runtimevsLive codingProblem-solving from scratch

Employers often use both; these tests cover the first.

Language before framework

1JavaScript or Python test2Then React, Node, Vue or Django3Gaps show up as framework bugs

Frameworks assume fluency in the language underneath.

Code and IQ

REASONING•Logic•Abstraction•Tracing state

LEARNED•Syntax•Libraries•Idioms

Experience matters more than raw reasoning for language knowledge.

Read the code. Find the bug.

What programming tests are, in short