Blog | Mazedul Islam - Full-stack Software Engineer

Writing & Notes

The Blog

What I learn building full-stack applications for clients: architecture decisions, AI integration, and the problems that only show up in production.

All Claude Code AI Coding Tools Developer Workflow Shell Node.js AWS EC2 Nginx PM2 Next.js Server Actions React Nodemailer Zod TypeScript Nest.js TypeORM PostgreSQL SQL CSS SASS SCSS Bootstrap

Diagram: the CLAUDE_CONFIG_DIR environment variable branching into two isolated profiles, claude pointing at ~/.claude and claude-work pointing at ~/.claude-work, each with its own login, history and quota, both running at once.

FeaturedCLAUDE CODE · WORKFLOW

Run Multiple Claude Code Accounts Without Logging Out

Client-provided Claude Code subscriptions mean a /login every time you switch, a real risk of billing the wrong client, and no way to leave a long task running. One environment variable fixes all three.

Aug 29, 20267 min read

Request flow from the internet through Nginx and PM2 to a Node.js API on an AWS EC2 instance

AWS · DEPLOYMENT

How to deploy a Node.js API on AWS EC2

Deploy a Node.js/Express API on an AWS EC2 Ubuntu instance with no prior AWS experience: launch the instance, install Node and PM2, clone from GitHub, and put Nginx in front as a reverse proxy.

Jun 10, 20244 min read

Diagram of a contact form posting FormData to a Next.js Server Action, which runs Zod validation and Nodemailer, returning either per-field errors or a success toast and form reset.

NEXTJS · SERVER ACTIONS

Full featured contact form with Next.js Server Actions

A Next.js contact form that runs Zod validation inside a Server Action, returns field-level errors to the inputs, and sends mail with Nodemailer. Built on React 19's useActionState, with a pending submit button and a toast on success.

Apr 1, 202413 min read

Two login requests both point to a single cached message object whose name placeholder has been overwritten, so both users receive the first user's name

NODE.JS · DEBUGGING

The Node.js Caching Bug That Shows Every User the Same Name

One user logs in and sees another user's name. No hardcoded value, no database problem, and it only reproduces after the second request. A walkthrough of shared mutable state in a cached Node.js object, and the one-line fix.

Jan 17, 20245 min read

NESTJS · TYPEORM

How to seed database using TypeORM in a NestJS project

Seed a Postgres database in NestJS using typeorm-extension: write a seeder class, generate fake users with a factory, and run it all from one npm script.

Aug 3, 20236 min read

NESTJS · TYPEORM

How to setup TypeORM migrations in a NestJS project

Point TypeORM at your .ts entities and you get "Cannot use import statement outside a module." Load them from dist instead, then wire up build-and-generate and build-and-run scripts in package.json.

Jul 27, 20236 min read

Diagram: a nested SASS @each loop over a $spacers map and $sides list, with an @if guard excluding auto for padding, generating 91 spacing utility classes such as m-0, mt-1, mx-3 and pt-3

SASS · CSS ARCHITECTURE

Generate bootstrap-like spacing classes in SASS

An easy and descriptive way of generating all the bootstrap-like spacing classes from SASS code.

Feb 4, 20227 min read