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OpenStem
@openstem · Joined Jul 2026
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Quiz5 questions
In which phase do setImmediate() callbacks run?
AThe timers phaseBThe check phaseCThe close callbacks phaseDThere is no dedicated phase for it
Software · L1 · Node.js: Event Loop & Modules Check
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Software · L1 · Node.js: Event Loop & Modules CheckQuiz5 questions
What is the correct order of steps when loading a fresh HTTPS page?
ATLS handshake, DNS lookup, TCP handshake, HTTP requestBDNS lookup, TCP handshake, TLS handshake, HTTP requestCHTTP request, DNS lookup, TCP handshake, TLS handshakeDTCP handshake, HTTP request, DNS lookup, TLS handshake
Software · L1 · Networking & HTTP: Request Anatomy Check
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Software · L1 · Networking & HTTP: Request Anatomy CheckQuiz5 questions
Which state is a process in while it waits for a disk read to complete?
ABlockedBRunningCReadyDTerminated
Software · L1 · Operating Systems: The Process Lifecycle
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Software · L1 · Operating Systems: The Process LifecycleQuiz5 questions
Why is `counter++` unsafe when called from two threads without synchronization?
AIt is really three steps (read, add, write) that can interleave between threadsBThe `++` operator doesn't exist in most languagesCIntegers can't be shared between threadsDIt only fails on single-core machines
Software · L1 · Concurrency: Protecting Shared State
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Software · L1 · Concurrency: Protecting Shared StateQuiz5 questions
Why must the server hash the incoming password before comparing it, rather than storing and comparing plaintext?
AHashing makes login fasterBIf the database leaks, hashed passwords can't be immediately used, unlike plaintextCHashing is required by HTTPSDIt lets users log in without a password
Software · L1 · Security & Auth: Login & Session Flow
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Software · L1 · Security & Auth: Login & Session FlowQuiz5 questions
What does `docker build` produce?
AA running containerBA local imageCA registry accountDA Dockerfile
Software · L1 · Docker & Kubernetes: Image Build & Deploy Lifecycle
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Software · L1 · Docker & Kubernetes: Image Build & Deploy LifecycleQuiz5 questions
Why must you see the test fail (Red) before writing the implementation?
AIt's a formality with no practical benefitBIt proves the test actually exercises the intended behavior and would catch a regressionCFailing tests run fasterDGreen-phase code doesn't compile without it
Software · L1 · Testing: The Red-Green-Refactor Cycle
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Software · L1 · Testing: The Red-Green-Refactor CycleQuiz5 questions
An object has 8 optional constructor parameters. Which pattern fits best?
ABuilderBSingletonCPrototypeDFactory Method
Software · L1 · Design Patterns: Choosing a Creational Pattern
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Software · L1 · Design Patterns: Choosing a Creational PatternQuiz5 questions
What is the first major thing SpringApplication.run() creates?
AThe ApplicationContextBThe embedded Tomcat serverCA CommandLineRunner beanDThe application.properties file
Software · L1 · Spring Boot: Application Lifecycle & Logging
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Software · L1 · Spring Boot: Application Lifecycle & LoggingQuiz5 questions
What is pubspec.yaml?
AThe project manifest declaring its name, SDK constraint, and dependenciesBA compiled binary produced by dart buildCA file that stores runtime log outputDThe entry-point Dart source file
Software · L1 · Dart: Packages & Tooling
@openstem
Software · L1 · Dart: Packages & ToolingQuiz5 questions
Where do you set an app-wide color scheme and typography in a Flutter app?
AIn a ThemeData passed to MaterialApp's `theme` parameterBIn every individual widget's constructorCIn the pubspec.yaml fileDIn a global CSS file
Software · L1 · Flutter: Styling & Theming
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Software · L1 · Flutter: Styling & ThemingQuiz5 questions
Where is a file placed at public/favicon.ico served from?
A/favicon.ico, at the site rootB/public/favicon.icoCIt is not served; public/ is build-onlyD/app/favicon.ico
Software · L1 · Next.js: Images, Fonts & Assets
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Software · L1 · Next.js: Images, Fonts & AssetsQuiz5 questions
What runs first when a request arrives at a Nest application?
AMiddlewareBGuardsCPipesDThe route handler
Software · L1 · NestJS: Architecture & Routing Check
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Software · L1 · NestJS: Architecture & Routing CheckQuiz5 questions
What is the main benefit of embedding related data as a subdocument?
AOne read retrieves the parent and its related data togetherBIt removes the 16MB document size limitCIt always uses less disk spaceDIt avoids needing an _id field
Software · L1 · MongoDB: Schema Design — Embedding vs Referencing
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Software · L1 · MongoDB: Schema Design — Embedding vs ReferencingQuiz5 questions
What does to_tsvector() do?
AConverts text into normalized, stemmed lexemesBDeletes a text columnCConverts text into JSONBDEncrypts a text value
Software · L1 · PostgreSQL: Full-Text Search
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Software · L1 · PostgreSQL: Full-Text SearchQuiz5 questions
Which AWS storage service is object storage accessed over HTTP?
AAmazon S3BAmazon EBSCAmazon EFSDAmazon RDS
Software · L1 · AWS: Storage Options Compared
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Software · L1 · AWS: Storage Options ComparedQuiz5 questions
Which GCP service is object storage accessed over HTTP?
ACloud StorageBPersistent DiskCFilestoreDCloud SQL
Software · L1 · Google Cloud: Storage & Database Options
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Software · L1 · Google Cloud: Storage & Database OptionsQuiz5 questions
Which command must run first in a new Terraform working directory?
Aterraform applyBterraform initCterraform destroyDterraform plan
Software · L1 · Terraform: The Core Workflow
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Software · L1 · Terraform: The Core WorkflowQuiz3 questions
What does this Scratch-style code do?
repeat 3 times:
move forward 10 steps
AMoves forward 10 steps onceBMoves forward 3 stepsCMoves forward 30 steps in total (10 each time, 3 times)DDoes nothing
Software · L2 · Loops, Conditionals, and Variables
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Software · L2 · Loops, Conditionals, and VariablesQuiz2 questions
Binary uses only two digits. Which two?
A1 and 2B0 and 1C0 and 9DA and B
Software · L2 · Binary and the Internet
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Software · L2 · Binary and the InternetQuiz5 questions
What does this log?
AA, B, C, DBA, D, C, BCA, D, B, CDD, C, B, A
Software · L2 · JavaScript: Event Loop Order
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Software · L2 · JavaScript: Event Loop OrderQuiz5 questions
Which utility type would you use to build a PATCH request body where every field of User is optional?
ARequired<User>BPartial<User>CReadonly<User>DPick<User, never>
Software · L2 · TypeScript: Utility Types
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Software · L2 · TypeScript: Utility TypesQuiz5 questions
You want to add `Point.from_tuple((3, 4))` as an alternative way to build a Point. Which decorator fits?
A@staticmethodB@classmethodC@propertyDNo decorator — use a plain instance method
Software · L2 · Python: classmethod vs staticmethod vs Instance Method
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Software · L2 · Python: classmethod vs staticmethod vs Instance MethodQuiz5 questions
When does a useEffect's cleanup function run?
AOnly when the component unmountsBBefore the effect re-runs (deps changed) and on unmountCImmediately before the render phase startsDIt never runs automatically
Software · L2 · React: Hooks & Effects Check
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Software · L2 · React: Hooks & Effects CheckQuiz5 questions
Which traversal is the natural choice for shortest path in an unweighted graph?
ABFSBDFSCIn-order traversalDBinary search
Software · L2 · Data Structures & Algos: Graph Traversal
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Software · L2 · Data Structures & Algos: Graph TraversalQuiz5 questions
Which caching strategy gives the strongest consistency between cache and database?
AWrite-throughBWrite-backCCache-aside with a long TTLDNo caching at all is more consistent
Software · L2 · System Design: Choosing a Cache Strategy
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Software · L2 · System Design: Choosing a Cache StrategyQuiz5 questions
Which isolation level prevents dirty, non-repeatable, and phantom reads?
ARead UncommittedBRead CommittedCRepeatable ReadDSerializable
Software · L2 · SQL: Isolation Levels & Locking
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Software · L2 · SQL: Isolation Levels & LockingQuiz5 questions
What does the `=======` marker separate inside a conflicted file?
ATwo unrelated filesBYour current branch's version from the incoming branch's versionCStaged changes from unstaged changesDCommit messages from diffs
Software · L2 · Git & Dev Workflow: Resolving a Merge Conflict
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Software · L2 · Git & Dev Workflow: Resolving a Merge ConflictQuiz5 questions
Multiple goroutines need exclusive access to a shared in-memory counter. What's the simplest fit?
AAn unbuffered channelBsync.MutexCsync.WaitGroupDselect
Software · L2 · Go: Concurrency Primitives
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Software · L2 · Go: Concurrency PrimitivesQuiz5 questions
A function looks up a key that may or may not be in a HashMap. What's the idiomatic return type?
AResult<V, E>BOption<V>CV, and panic! if missingDbool
Software · L2 · Rust: Option, Result, and panic!
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Software · L2 · Rust: Option, Result, and panic!