Search

Lessons (39)

• Reusable Modules and Clear Interfaces

  Build and call a small module, expose outputs, and define sensible module ownership and versioning. A module is …

• Atomic Design & Component Libraries

  Build consistent, reusable interfaces by composing small UI primitives into components, layouts and real pages—without forcing every …

• Advanced TypeScript for Frontend

  … The status field narrows the type for each branch. Use generics for reusable contracts Generics preserve information instead …

• Your Practical Kubernetes Workflow

  … a reusable Kubernetes package One app usually needs several YAML files: a Deployment, Service, Ingress, settings, and possibly …

• I — Interface Segregation Principle

  … Any change to User can affect it, // and it is hard to reuse or test. function Avatar({ user …

• Payment Retries: Prevent Duplicate Charges

  … Reject reuse of the key with a different amount. Send the same key to the provider: your database …

• SQL Language, Identifiers & Data Types

  … A sequence is a reusable database counter. UUIDs can be generated without a central counter and help distributed …

• React Fundamentals

  … small, reusable bricks ( components ) snap together into bigger ones, and the bigger ones form the whole page. And …

• Serverless Architecture

  … DynamoDBDocumentClient.from(new DynamoDBClient({})); // created ONCE per container, reused export const handler = async (event: { body: string }) = { const input …

• React Hooks in Practice

  … changing global state, see State Management . Custom hooks: reuse logic Any function starting with use that calls other …

• Environments, Workspaces, and Multiple Accounts

  … database, while production enables replicas and deletion protection. Reuse the underlying module rather than copying its entire implementation …

• Serverless: Lambda and API Gateway

  … Keep startup work modest and reuse safe SDK/database client objects where appropriate. Never depend on local memory …

• Terraform: Start Here

  … its tags Module A directory of Terraform configuration Reusable private storage module Backend Where state is stored and …

• API Contracts, Gateways and Security

  … For mutations, define idempotency scope and reject mismatched key reuse. Apply per-identity limits and avoid recording credentials …

• A WhatsApp OTP Is Only Single Use If You Make It So

  … Kill the process between consume and session creation and assert the code cannot be reused. Check that no …

• Scalable Frontend Architecture

  … Shared code must be genuinely reusable and domain-neutral. text app/orders/[id]/page.tsx route composition and …

• What Are Design Patterns?

  Design patterns are named, reusable solutions to problems that keep coming up in software design. Meet the three …

• Resilient Service Calls: Retries, Breakers and Load Shedding

  … Use one durable idempotency key per user action, such as pay:order-981:attempt-1 , and reuse it …

• DRY: Don't Repeat Yourself

  … places A repository function Repeated UI markup A reusable component mermaid flowchart LR S["📜 One Zod schema<br …

• Python and Math Foundations with Runnable Examples

  … remain consistent. - Fit preprocessing on training examples and reuse it at inference. - Similarity, probability, and evaluation scores mean …

• Small Functions That Do One Thing

  Short, focused functions are easy to name, test and reuse. Learn how to spot a function doing too …

• Developer Learning Plan and Document-Assistant Capstone

  … Existing web developers can reuse API, authentication, testing, and deployment skills. Stage Learn Build Completion evidence --- --- --- --- Week 1 …

• Docker & Containers

  … Docker reuses unchanged layers, so order matters : put things that change rarely first. mermaid flowchart TB L1["FROM …

• TypeScript Essentials

  … make impossible states impossible. - Generics are type parameters: reusable, type-safe functions and components. - Utility types ( Partial , Pick …

• DynamoDB Modeling, RDS Scaling and Data Resilience

  … and exhaust the database. RDS Proxy pools and reuses connections, and speeds up failover because apps stay connected …

• CloudFront: Faster Websites and Safer File Delivery

  … Why might caching be involved? A shared cache key or policy allowed personalized responses to be reused across …

• TypeScript in Practice

  … exhaustive check. - Generics with extends and keyof give reusable code that stays precise. - Derive types ( Pick , Omit , mapped …

• Concurrency, Resilience & Distributed Workflows

  … Connection pools and distributed tracing A connection pool reuses expensive database connections, but the pool is not infinite …

• 10,000 Users Do Not Need 10,000 Database Connections

  … Transaction pooling can reuse a smaller set of server connections, but it has compatibility constraints: session state, prepared …

• Backend Design Scenarios

  … Use provider-specific rate limits, bounded worker concurrency, connection reuse, backoff with jitter and a dead-letter queue …

• Run Containers on AWS with ECR and ECS

  … behavior, then roll back to the recorded revision. Reusing a mutable tag makes this evidence harder to interpret …

• Structural Patterns: How to Connect Objects

  … getTreeType("oak", "oak.png"), // all share ONE object })); You've used it: string interning, React reusing element types …

• Python Fundamentals

  … add item(item, bucket=[]): ❌ the same list is reused on every call bucket.append(item); return bucket def …

• L6 Production Debugging Casebook

  … See [database scaling](./database-internals-and-scaling). Reusable incident worksheet For any production symptom, record: 1. Impact: which …

• Practical Project: Deploy a Real CRM App on EKS

  … The fix belongs in code: - Reuse one Prisma client per process. - Prevent overlapping relay iterations (wait for one …

• Scaling, Load Balancing & Rate Limiting

  … 5. Connection management: reuse connections, apply timeouts and limit slow clients. 6. Protection: enforce request-size limits, quotas …

• Caching & Redis

  … rarely re-read, highly personalised data with no reuse. Where should you cache? Choose the closest layer that …

• C4 Architecture Diagrams: Context, Container, Component and Code

  … components. --- An easy five-step method you can reuse Draw the context diagram 1. Write the system name …

• Practical Lab: S3 File Upload and CloudFront Delivery with NestJS

  … bash Set these once per terminal session and reuse them in every command below. export REGION=us-east …