Make it yours.Save notes, decks & boards to your own library.

openstem

Explore

Spaces

My Library

All fields Software Mathematics Physics Chemistry Biology Engineering Astronomy Environmental Other Software Software groups

Explore STEM Content

Search the community's STEM library — free to study, yours to make your own.

Software

Programming, algorithms and systems on openstem — flashcards, notes, quizzes, sketches and flowcharts shared by the community. Study free, or clone anything into your library.

Content Groups1

Loading…

loading…

About Privacy Terms of Service© openstem

We use privacy-friendly product analytics (no session recording, PII masked) to improve OpenStem. Load analytics? Privacy Policy

openstem

Explore

Groups Favorites

Collections Notes Flashcards Quizzes Sketches Flowcharts Plots Molecules

Make it yours.Save notes, decks & boards to your own library.

Get started Sign in

Explore Groups Favorites

Software: explore STEM content (page 14 of 25) · openstem

All fields Software Mathematics Physics Chemistry Biology Engineering Astronomy Environmental Other Software Software groups

Explore STEM Content

Search the community's STEM library — free to study, yours to make your own.

Software

Programming, algorithms and systems on openstem — flashcards, notes, quizzes, sketches and flowcharts shared by the community. Study free, or clone anything into your library.

Content Groups1

Loading…

Collection2 items

01Rendering Pipeline: Widget / Element / RenderObject

02Performance, Slivers & Custom Rendering

Software

Software · L4 · Flutter

@openstem

Software · L4 · Flutter

Quiz5 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

Software · L1 · Next.js: Images, Fonts & Assets

@openstem

Software · L1 · Next.js: Images, Fonts & Assets

Quiz5 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

Software · L1 · Flutter: Styling & Theming

@openstem

Software · L1 · Flutter: Styling & Theming

Quiz5 questions

What does `0 ?? 5` evaluate to?

A5B0CundefinedDNaN

Software

Software · L1 · TypeScript: Optional & Nullish Values

@openstem

Software · L1 · TypeScript: Optional & Nullish Values

Flashcards10 cards

What is a goroutine?1 / 10

A lightweight thread managed by the Go runtime, started with the `go` keyword. Goroutines are multiplexed onto OS threads by the scheduler, are very cheap (~2KB initial stack), so you can run hundreds of thousands concurrently.

Software

Goroutines & Channels

@openstem

Goroutines & Channels

Flowchart9 objects

Software

Software · L1 · Next.js: Images, Fonts & Assets · flowchart

@openstem

Software · L1 · Next.js: Images, Fonts & Assets · flowchart

Quiz7 questions

Why do protocols like TLS use asymmetric crypto only for the handshake, not for bulk data?

AAsymmetric ciphers can't encrypt more than a few bytes at allBAsymmetric crypto is far slower than symmetric crypto, so it's used only to establish a shared session keyCSymmetric ciphers can't be implemented in hardwareDAsymmetric crypto is actually faster and preferred for everything

Software

Software · L4 · Applied Cryptography — 7 Q

@openstem

Software · L4 · Applied Cryptography — 7 Q

Collection4 items

01Indexes & Performance

02Window Functions

03Software · L2 · SQL: Isolation Levels & Locking

+1 more

Software

Software · L2 · SQL

@openstem

Software · L2 · SQL

Collection2 items

01Advanced Types (Conditional & Template Literal)

02Type-Level Programming

Software

Software · L3 · TypeScript

@openstem

Software · L3 · TypeScript

Flowchart11 objects

Software

Software · L1 · Putting Steps in Order

@openstem

Software · L1 · Putting Steps in Order

Collection2 items

01Spring Security

02Data Access & JPA

Software

Software · L3 · Spring Boot

@openstem

Software · L3 · Spring Boot

Quiz6 questions

Two operations from different transactions 'conflict' when...

AThey both read the same data itemBThey belong to transactions that started at the same timeCThey access the same data item and at least one of them is a writeDThey appear in different tables of the schema

Software

Software · L5 · Database Theory & Query Optimization

@openstem

Software · L5 · Database Theory & Query Optimization

Flowchart9 objects

Software

Software · L1 · Java: Classes & Objects · flowchart

@openstem

Software · L1 · Java: Classes & Objects · flowchart

Flowchart13 objects

Software

Software · L1 · SQL: Transactions & ACID · flowchart

@openstem

Software · L1 · SQL: Transactions & ACID · flowchart

Note~135 words · 1 min

One Job Each TypeScript's built-in utility types each transform an existing type in exactly one way. Reaching for the wrong one — or hand-writing a mapped type that already exists as a utility — makes signatures harder to read for no benefi

Software

Software · L2 · TypeScript: Picking the Right Utility Type

@openstem

Software · L2 · TypeScript: Picking the Right Utility Type

Flashcards9 cards

What is an error budget and what does it govern?1 / 9

The error budget is 1 minus the SLO (e.g. 99.9% SLO leaves a 0.1% budget) — the amount of unreliability the business tolerates over a window. It governs the release/risk tradeoff: while budget remains, teams can ship features and take risks; once it's exhausted, the org shifts focus to reliability work (freezing risky launches) until the budget recovers.

Software

Site Reliability Engineering

@openstem

Site Reliability Engineering

Quiz5 questions

What does a MongoDB secondary replicate from the primary?

AThe oplog (operation log)BA nightly mongodump backupCThe query planner cacheDThe connection pool

Software

Software · L2 · MongoDB: Replica Sets & Failover

@openstem

Software · L2 · MongoDB: Replica Sets & Failover

Flashcards9 cards

What is the difference between a list and a tuple?1 / 9

Lists are mutable (modifiable in place) and use more memory. Tuples are immutable and hashable, so they can be dict keys or set members. Use tuples for fixed records, lists for collections you need to mutate.

Software

Core Types

@openstem

Core Types

Collection4 items

01Comprehensions & Iteration

02OOP & Classes

03Software · L2 · Python: classmethod, staticmethod, or Instance Method?

+1 more

Software

Software · L2 · Python

@openstem

Software · L2 · Python

Flashcards10 cards

What core benefit does a message queue provide between services?1 / 10

Asynchronous decoupling: producers and consumers operate independently, buffering load spikes and improving resilience.

Software

Message Queues & Streaming

@openstem

Message Queues & Streaming

Flashcards10 cards

What is a Terraform provider?1 / 10

A provider is a plugin that implements resource and data source types for a platform (AWS, GCP, Kubernetes), translating Terraform config into API calls.

Software

Providers & Resources

@openstem

Providers & Resources

Flowchart19 objects

Software

Software · L5 · Process Calculi Landscape

@openstem

Software · L5 · Process Calculi Landscape

Flowchart9 objects

Software

Data & Optimization · flowchart

@openstem

Data & Optimization · flowchart

Flowchart12 objects

Software

Software · L1 · Terraform: The Core Workflow · flowchart

@openstem

Software · L1 · Terraform: The Core Workflow · flowchart

Flowchart9 objects

Software

Software · L1 · Concurrency: Protecting Shared State · flowchart

@openstem

Software · L1 · Concurrency: Protecting Shared State · flowchart

Flashcards9 cards

What is a first-class function?1 / 9

Functions in Python are first-class objects — they can be assigned to variables, passed as arguments, returned from other functions, and stored in data structures.

Software

Functions & Decorators

@openstem

Functions & Decorators

Flashcards10 cards

What does the 'S' in SOLID (Single Responsibility) mean?1 / 10

A class should have only one reason to change — one responsibility. Mixing concerns (e.g. business logic + persistence + formatting) makes code fragile and hard to test. Split responsibilities into focused units.

Software

SOLID Principles

@openstem

SOLID Principles

Note~168 words · 1 min

The public/ Folder Files placed in `public/` are served as-is from the site root: `public/logo.png` is reachable at `/logo.png`. It's the right place for a favicon, robots.txt, or any static file that doesn't need processing. next/image: Op

Software

Software · L1 · Next.js: Images, Fonts & Assets

@openstem

Software · L1 · Next.js: Images, Fonts & Assets

Note~105 words · 1 min

Delegated Access Without Sharing Passwords The authorization code flow lets a third-party client obtain limited access to a user's account on another service, by routing the login through that service's own authorization server. Public clie

Software

Software · L2 · Networking & HTTP: OAuth 2.0 Authorization Code Flow

@openstem

Software · L2 · Networking & HTTP: OAuth 2.0 Authorization Code Flow

Quiz5 questions

In which phase do setImmediate() callbacks run?

AThe timers phaseBThe check phaseCThe close callbacks phaseDThere is no dedicated phase for it

Software

Software · L1 · Node.js: Event Loop & Modules Check

@openstem

Software · L1 · Node.js: Event Loop & Modules Check

‹ PrevPage 14 of 25Next ›