What is a tech stack?
A tech stack (short for "technology stack") is the combination of programming languages, frameworks, libraries, databases, and tools used to build and run a software product. The name comes from the idea of layers stacked on top of each other — the front end a user sees, the back end that powers it, the database that stores data, and the infrastructure it all runs on.
When people ask "what's your stack?", they mean: which specific technologies did you choose at each layer? Answering "React, Node.js, PostgreSQL, and AWS" describes a stack the same way "brick, steel, and glass" describes a building.
The layers of a tech stack
Most stacks break down into a few layers. Each has many options, and your choices at each layer make up your stack:
- Front end (client): what runs in the browser or app — e.g. React, Vue, Angular, or Svelte, plus HTML/CSS
- Back end (server): the logic and APIs — e.g. Node.js, Python/Django, Ruby on Rails, Go, or Java
- Database: where data lives — e.g. PostgreSQL, MySQL, MongoDB, or a managed option like Supabase or Firebase
- Infrastructure & DevOps: hosting and delivery — e.g. AWS, Vercel, Netlify, Docker, and CI/CD pipelines
Tech stack examples
Some combinations are common enough to have names. The MERN stack is MongoDB, Express, React, and Node.js — an all-JavaScript stack popular for web apps. MEAN swaps React for Angular. The LAMP stack (Linux, Apache, MySQL, PHP) powered much of the early web. Big companies mix and match: a "Netflix tech stack" spans Java, React, and a huge AWS footprint.
There is no single best stack — the right one depends on what you're building, your team's skills, and how you plan to scale.
How to choose your tech stack
Start from the project, not the trend. Consider the type of app (simple site, SaaS, marketplace, mobile), your team's existing skills, how fast you need to ship, and your scaling and budget needs. A weekend prototype and a product built to serve millions call for very different choices.
If you're not sure, CraftMyStack takes the guesswork out: describe your project and it recommends a coherent, modern stack across every layer — then lets you compare tools and build it out.