Beginner
34 bites tagged Beginner — interview questions with model answers, and 60-second explainers.
Unit testing vs component testing in React Native
Unit tests verify isolated functions/logic with Jest; component tests render components and assert behavior with React Native Testing Library. testing taxonomy.
How do you send a one-off event from native to JS?
Emit an event from native using an event emitter and subscribe in JS with NativeEventEmitter, or resolve a promise/callback for a single result. native-to-JS communication basics.
Explain the difference between Kotlin's let, run, with, apply, and also
Group by this (apply, run, with) vs it (let, also), then by return type. Whether you know the two axes of Kotlin scope functions: receiver (this vs it) and return value (context vs lambda result). Using them randomly.
Create a counter where clicking '+' increases the number by one
Tests Figma number variables and Set variable action. Use a number variable on the text, then add an On click trigger on the plus button with Set variable and an expression to add one. Red flag: using duplicate frames instead of a single dynamic variable.
How do you restore one component from Figma version history?
Tests whether you know version history is file-level. Answer: open the file name menu, show version history, find the ~1h autosave, duplicate it to a new file, copy the component, paste back. Red flag: restoring the entire old version and losing later work.
Steps to publish color and text styles to a Figma shared library
Open Publish in the right panel, select color and text styles, add a version note, publish; teammates enable the library. Figma shared-library mechanics. Manual copy-paste instead of publish-subscribe.
Explain what TypeScript's type inference is and show an inferred variable declaration
This tests whether you understand TypeScript deduces types without annotations. A strong answer defines inference as deriving types from values and gives an example like let x = 3 inferring number. A red flag is claiming explicit types are required.
What is the difference between async def and regular functions?
This tests async def call semantics. A strong answer contrasts regular functions, which execute immediately, with async def, which returns a coroutine object that does nothing until awaited or wrapped in create_task.
How do you declare a function as a dependency, and why?
Tests FastAPI dependency injection basics. Answer: create a function, import Depends, and add it to path operation parameters so FastAPI injects it. Purpose: routes declare what they need instead of hard-coding shared logic.
JWT: Signed JSON Claim Tokens
A JWT is a signed JSON envelope: it carries claim assertions in JSON, optionally encrypted, and proves who wrote it using either a private secret or a public/private key. Do not treat the payload as hidden unless encryption is actually enabled.
Node.js Built-in SQLite Driver
Node.js bundles a SQLite driver in node:sqlite. Open a file with new DatabaseSync(path), then run SQL with exec() or prepared statements. Use it for local tools and caches. DatabaseSync is synchronous, so running it on a web server main thread blocks requests.
Node.js Callbacks: Functions That Run Later
A callback is a function you pass to run later when an event fires or work finishes, keeping Node.js free to handle other work. HTTP servers use them to respond to connections without blocking.
What are the essential components of an end-to-end ML platform?
Tests mapping the ML lifecycle to infrastructure. A strong answer walks through six stages: data ingestion, feature store, training pipeline, model registry, deployment/serving, and monitoring with feedback loops.
What are Rust's two macro categories and use cases?
Name macro_rules! for syntax like vec!, and procedural macros for custom derive on structs. Whether you know Rust's declarative versus procedural macro distinction. Calling them C-style substitution or runtime code.
How do you initialize and manage Go dependencies?
Init with go mod init; use go get and go mod tidy; go.mod sets path and versions, go.sum stores checksums for verified builds. Go Modules workflow knowledge. saying go.sum is optional or that go.mod pins exact content.
What is the difference between defining a Rust trait and implementing it?
Define with trait and signatures; implement with impl Trait for Type and concrete bodies. Knowledge of declaration versus implementation in Rust traits. Mixing up traits and structs or omitting for.
Describe Go's memory management, garbage collection, and trade-offs
Explain Go's GC recycles heap memory, the compiler stack-allocates locals, and automatic collection costs runtime overhead. automatic memory management and stack versus heap division.
Go package declaration, directory name, and import path relationship
Tests Go's separation of directory layout and package identity. A good answer states: import path is module path plus subdirectory; package clause is the in-code name; mismatch is legal and common for main or tests.
Define a WebEvent enum with PageLoad, PageUnload, and KeyPress
Tests Rust enum syntax: unit versus tuple variants. A good answer defines WebEvent with PageLoad, PageUnload, and KeyPress(char), then instantiates WebEvent::KeyPress('q'). A red flag is forgetting the double colon or using struct variant syntax.
In a Row, how do you space children evenly across the width?
Set mainAxisAlignment to spaceEvenly; contrast with spaceBetween and spaceAround. Row main-axis layout and MainAxisAlignment. Using manual SizedBox spacers instead of the built-in alignment enum.
DDL: The Blueprint for Database Objects
DDL is the blueprint for your database. You reach for it when spinning up new tables, indexes, or user permissions, not when querying rows. The footgun is running DROP thinking you are deleting data, not vaporizing the entire table structure.
The 4 P's Formula: Picture, Promise, Prove, Push
The 4 P's formula structures persuasive copy in four steps: picture, promise, prove, push. It shines in emails and landing pages that must convert attention fast.
AWS SDK: Code That Operates Your Cloud
The AWS SDK turns AWS API calls into native code so your app can command S3 or DynamoDB directly. It handles auth, retries, and formatting automatically. The footgun: forgetting region or credentials causes silent failures that look like network errors.
Describe the Terraform workflow from code to live
This tests Terraform workflows beyond local commands. A strong answer covers: version-controlled code, terraform plan for speculative validation, then terraform apply via remote runs with policies. Red flag: only local apply without reviews or remote state.
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