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Series28 chapters - about 64 min total

Englishবাংলা

From Frontend to Full-Stack Backend

A 4-week backend course, in blog style. From building APIs in a clean structure with Node, Express and TypeScript, through SQL, MongoDB, Prisma, Redis, Queues, Security, Real-time, NestJS and System Design. Each episode takes 5-7 minutes to read, with real examples, code, common mistakes, practice tasks and interview tips.

Week 1 - API Foundation

  1. 01What a REST API really is - through a frontend dev's eyes3 min read
  2. 02Project structure and the middleware chain - keeping big codebases tidy2 min read
  3. 03Middleware in depth - the full journey of a request2 min read
  4. 04Validation layer - stopping bad data at the door with Zod2 min read
  5. 05Auth part 1 - JWT access tokens and bcrypt hashing2 min read
  6. 06Auth part 2 - Refresh token rotation, httpOnly cookies and role-based access3 min read
  7. 07End of week 1 - putting the whole picture together2 min read

Week 2 - Database Depth

  1. 08SQL in depth - when to use JOIN, GROUP BY and subqueries2 min read
  2. 09Indexes and performance - catching and fixing slow queries2 min read
  3. 10Transactions and ACID - half-done work means total chaos2 min read
  4. 11MongoDB schema design - embed or reference2 min read
  5. 12MongoDB aggregation pipeline - building reports with the database itself2 min read
  6. 13Prisma - schema, migration, relations and the N+1 problem2 min read
  7. 14End of week 2 - giving the API its real shape with complex queries2 min read

Week 3 - Most Asked Interview Topics

  1. 15Caching - Redis, the cache-aside pattern and the hard invalidation question3 min read
  2. 16Queues - pushing slow work to the background with BullMQ3 min read
  3. 17Security - rate limiting, what CORS really is, and helmet3 min read
  4. 18File upload - multer, validation and the S3 presigned URL idea3 min read
  5. 19Real-time - notification and chat basics with Socket.io3 min read
  6. 20Production-level API - offset vs cursor pagination and logging3 min read
  7. 21End of week 3 - weaving Redis cache and background jobs into the API2 min read

Week 4 - Capstone + NestJS + System Design + Drill

  1. 22Capstone begins - requirements and schema on paper, before code2 min read
  2. 23Capstone part 1 - auth, roles and core CRUD2 min read
  3. 24Capstone part 2 - the complex feature that sets the project apart2 min read
  4. 25NestJS crash course - a new framework through Express experience2 min read
  5. 26System design practice - drawing architecture on paper2 min read
  6. 27Testing and deployment - bringing the project before the world2 min read
  7. 28Final mock drill - say it out loud, not in writing2 min read