Software Engineer 路 Intern to senior
General software engineering interviews are usually language-agnostic. Expect a coding problem, questions about how a language you know works under the hood, a design discussion and behavioral questions about how you work with a team.
112 questions
Connect two or three of your strongest, provable skills directly to the needs in the job description, give a short piece of evidence for each, and show genuine interest in the team鈥檚 work.
Give specific evidence of deliberate learning through projects, feedback, reading, experimentation or mentoring rather than listing technologies.
Connect something specific about the company, product, engineering challenges or team to your own experience and career goals.
A const is a compile-time constant that must be assigned where it is declared, while a readonly field can be assigned at declaration or in the constructor, so its value can be decided at runtime.
Both pass an argument by reference, but ref requires the variable to be initialised before the call, while out requires the method to assign a value before it returns.
*args collects extra positional arguments into a tuple and **kwargs collects extra keyword arguments into a dictionary, which lets a function accept a variable number of arguments.
Vertical scaling means giving one machine more CPU, memory or disk, while horizontal scaling means adding more machines and spreading the load across them.
Volumes are storage managed by Docker that lives outside a container鈥檚 writable layer, so data such as database files survives when the container is removed or replaced.
The test pyramid is a guideline to have many fast unit tests at the base, fewer integration tests in the middle and only a small number of slow end-to-end tests at the top, so the suite stays fast and reliable.
Walk through the array once while storing each number鈥檚 index in a hash map; for every number, check whether target minus that number is already in the map. This runs in O(n) time and O(n) space.
A closure is a function that keeps access to the variables of the scope where it was created, even after that outer function has finished running.
this is decided by how a function is called, not where it is written: as a method it is the object before the dot, with new it is the new object, and arrow functions inherit it from the enclosing scope.
async/await is syntax built on top of promises that lets you write asynchronous code that reads like synchronous code; under the hood every async function returns a promise.
Event delegation means attaching one listener to a parent element and using event bubbling to handle events from its children, instead of adding a listener to each child.
An abstract class can hold state, constructors and partial implementation but a class can inherit only one, while an interface defines a contract that a class can implement many of.
Boxing converts a value type to object by allocating it on the heap, and unboxing converts it back; both add allocations and casts, so avoid them in hot code paths.
LINQ (Language Integrated Query) lets you query collections, databases and XML with a consistent syntax, and deferred execution means a query does not run when you define it but when you enumerate the results.
An abstract class can have instance fields, constructors and a mix of implemented and abstract methods but supports only single inheritance, while an interface defines a contract that a class can implement multiple times and, since Java 8, can include default methods.
ArrayList is backed by a resizable array with O(1) index access and O(n) insertion in the middle, while LinkedList is a doubly linked list with O(n) index access and O(1) insertion once you hold the node; in practice ArrayList is faster for most workloads.
Checked exceptions (subclasses of Exception other than RuntimeException) must be caught or declared with throws, while unchecked exceptions (RuntimeException and Error) do not have to be handled and usually signal programming bugs.