Every backend engineer has a ritual. A new project lands on your plate, and before you write a single line of business logic, you spend the next hour — sometimes two — doing the same mechanical work you've done a dozen times before. Initialize npm, install Express, wire up Mongoose, configure TypeScript, set up a logger, write error middleware, decide on a folder structure, and repeat. None of it is intellectually challenging. All of it is time you're not spending on the thing that actually matters: building the product.
This is the problem that yapper was built to solve. It's a command-line tool that scaffolds a production-ready Express + Mongoose backend in seconds, with TypeScript, error handling, logging, and a sensible folder structure included from the start. The premise is simple — if the setup is predictable, it should be automated.
What Yapper Actually Does
At its core, yapper has two primary commands. The first is yapper new <project-name>, which bootstraps a complete backend project. This isn't just a package.json and an empty index.ts. The generated project includes an Express server, a Mongoose database connection, a configured TypeScript setup, request logging middleware, and a centralized error handler. Everything you'd normally spend an hour wiring together is already in place.
The second command is yapper generate module <name>. This is where the day-to-day value becomes immediately tangible. Instead of manually creating four or five files every time you add a new domain to your application, yapper generates a model, controller, service, and routes file inside a dedicated module directory — all consistently structured and typed. Adding a user, order, or notification module goes from a tedious multi-file exercise to a single terminal command.
The Folder Structure Is an Opinionated Choice, and That's the Point
One of the quieter but more important decisions in yapper's design is its commitment to a fixed, opinionated folder structure. Rather than co-locating all domain concerns under a single modules/ directory, yapper separates by layer. Running yapp user, for instance, generates four files spread across dedicated top-level directories: src/schemas/user.schema.ts, src/services/user.service.ts, src/controllers/user.controller.ts, and src/routes/user.route.ts.
This is a classic layered architecture pattern, and the choice is deliberate. Each directory has a single, well-understood responsibility — schemas define the shape of your data, services hold business logic, controllers handle the HTTP layer, and routes wire everything together. When you're debugging a production issue or reviewing a pull request, you don't need to think about where to look. The structure tells you.
Critically, none of these files are empty stubs. Every generated file comes pre-filled with standard CRUD boilerplate that is fully wired up and ready to be imported into your main application. You're not just getting a skeleton — you're getting a functional starting point that can handle create, read, update, and delete operations without writing a single additional line until your business logic demands it.
This might feel constraining if you have strong architectural opinions. But for most teams, especially during early-stage development or when onboarding new engineers, a predictable, consistent layout is worth far more than flexibility you'll rarely use. A new team member shouldn't need to reverse-engineer where the order service lives. The structure should communicate that for them, immediately and unambiguously.
TypeScript From Day One
Yapper generates typed models and controllers out of the box, which is a deliberate choice. TypeScript adoption is no longer optional on most serious Node.js projects — it's expected. Skipping it during initial setup and retrofitting it later is substantially more painful than starting with it. Yapper treats TypeScript as a first-class requirement rather than an optional add-on, which means the tsconfig.json, the typed Mongoose schemas, and the controller interfaces are all present from the moment the project is scaffolded.
When Yapper Makes Sense
Yapper is particularly well-suited for a few recurring scenarios. The most obvious is rapid prototyping — when you need a functional backend to validate an idea and setup time is pure overhead. It's equally valuable in team environments where consistency across services matters. If every microservice in your organization follows the same structural conventions, code review, debugging, and onboarding all become faster. It's also a useful teaching tool, where the overhead of explaining project configuration can derail the actual lesson.
Customization and Escape Hatches
An opinionated tool is only useful if its opinions don't trap you. Yapper's module templates are designed to be overridable, so if your team prefers a hexagonal architecture, or uses a specific validation library like Zod or class-validator, you can modify the generated templates to reflect those choices. The logging implementation can be swapped out. The Docker configuration included in the scaffold gives you a starting point for containerized development and CI/CD pipelines without locking you into any specific toolchain.
The defaults exist to get you moving. They're not meant to be permanent. The expectation is that you'll adapt them to your context once the project has found its footing.
Reinventing the same project skeleton is one of those low-visibility costs that doesn't show up on a roadmap but quietly drains engineering time across every team. Yapper addresses that directly not by being clever, but by being consistent and fast. If you're starting a new Express backend, the question worth asking is whether you'd rather spend the first hour on setup or on features. Yapper is built for the latter.
Yapper is an open project, and contributions are genuinely welcome — whether that's a bug report, an architectural suggestion, or a pull request that improves the generated templates. If you've found a pattern that works better in production, or a default that doesn't hold up in real-world usage, opening an issue or submitting a PR is the right way to get it in. Good CLIs get better through the friction of real projects, and feedback from engineers using the tool in anger is more valuable than any amount of pre-release design work.
If you find yapper useful in your workflow, the most direct way to support the project is to give the repository a star on GitHub. It's a small gesture, but it helps the project surface to other engineers who are solving the same problem.
