» How to be MEAN!


Photo: "IMG_4236" image courtesy of middlewick .

Bringing a Web application from the spark of an idea to a complete interactive experience is certainly a rite of passage. I finished programming my first complete Web application this week using the MEAN stack (MongoDB, Express, AngularJS, Node.js), and while I can already see what I would do differently next time, my time spent with this project has had tremendous value.

Building a Web application is a journey that requires familiarity with so many topics that at the end you feel as if no concept in this domain is beyond reach. While it's true that genuine expertise requires repetition, every student of technology interested in the Web should build a full app at least once. It's worth it.

If life is a road continually traveled, I look back now and marvel at the distance I covered these past months. Finishing the Hacka_finder prototype was very gratifying. Taking on a solo project this large taught me more than I ever learned in a classroom, and I want to share with my fellow adventurers some of what I discovered along the way.

Finding Your Footing

Having the idea for an app is easy. Everybody has ideas. However, building that idea into an application is a monumental task, so much so that planning your first expedition into the unknown is daunting. There is not one single book that teaches everything needed for this project. This would be like looking for a book that teaches how to paint every imaginable kind of picture. I submit that both development and painting are art fused with craft except one skill set produces an application and one produces a painting.

As with anything complex, take it one step at a time. I researched which technologies interested me before writing a single line of code. I found, borrowed, and purchased six different books on topics ranging from MongoDB database administration to building a front-end with AngularJS, not to mention the many API references for tools like Grunt and Yeoman that I knew through research to be essential. Understanding what a tool can do before using it can only lead to stronger craft.

When looking for a concrete place to begin, Yeoman is an excellent tool. The generators it sports are not all perfect, but I found it very helpful to see an opinion on how to scaffold a large project while planning my own.

The Red Pill

One thing six books and countless API documents did not tell me is this: Code that runs a Web application like this consists of 95% connective boilerplate to support the 5% that runs the core idea behind an app. Building the Hacka_finder prototype took me a little over 2 months from start to finish. I wrote code to work with MongoDB, code to authenticate user sessions, code to manage the API requests and responses, but perhaps only three functions total that actually search the user data for a query match. This was quite eye opening!

Front or Back

Single-page applications (SPA) run mostly in the browser. This is different from a more traditional approach that puts everything on the server. For most people and most projects, I suspect the approach taken is largely irrelevant. Just use the technologies you like best. I chose the MEAN stack because I love functional programming, and JavaScript is both ubiquitous and rides the line between functional and object-oriented styles. If I could have built the entire stack in Haskell or Python, I may have done that instead, but I wanted to place my focus squarely on learning how to build an application rather than pushing the edges of possibility. "One language to rule them all" on both the client and the server appealed to me.

An important consideration when building an SPA is security. In short, nothing you do at the browser is safe. API responses can be intercepted, code can be viewed, and if not careful, data from application users can be harvested. However, SPAs are great for pushing the processing requirements for an app out of your server and onto the computers of your app users. This is why SPA architecture has become popular. Just be careful how you handle your sensitive data!

A Schema is a Road Map

Create the database schema first. MongoDB does not require a schema per se unlike the more traditional SQL-style databases, but for me, knowing what data points I wanted to store made all the difference in how easy it was to visualize my data structure when writing functions. I put my schema into a spreadsheet so I knew what my data models looked like at a glance. At any given time I understood which part of the database would be active and what the response from the database would contain. MongoDB itself was quite easy to use; I would use it again.


My business roots are going to show here, but branding is important. The graphic design of your app flows entirely from the logo. It defines the colors, personality, and feelings a visitor has when viewing your app, so spend some time on the logo. Good design, like good program architecture, is not an afterthought. It makes business sense because well-reasoned graphic design is more memorable. There is so much application saturation between all the competing Web apps, mobile apps, video game software, and so on that you cannot afford to give users a reason to hate the experience. Branding is much more than graphic design, but it does start there, so spend a dime to buy some time.

Front End

I have planned website projects with Balsamiq, Axure, Photoshop, and Illustrator. While these are all good tools, theme design in this project worked best with vanilla HTML and Sass. Here's the thing: While you can build a design in these other tools, you still have to program it at some point. I found that by starting with code, it was much faster to port the design into my JavaScript framework. The stylesheets carry over as is. If you remember to base your responsive theme styles on the mobile experience first and layer rules for other screen sizes on top using media query breakpoints, nothing more has to be done when porting. The HTML can be popped apart with relative ease for use with Angular's ngInclude directive. Starting the theme design in code was a good decision. Of course, designing for stakeholders is different from designing for yourself, so your mileage may vary.

With regard to AngularJS, there are all kinds of opinions on whether two-way data binding is valuable and if AngularJS is faster or slower than other JavaScript framework options out there (and there are many options out there.) My opinion is if you like a "batteries included" approach, you will probably like the current AngularJS iteration. It has everything needed to build an app, and having this all in one place was quite helpful for my first time building a full-scale Web application. I cringe a little at mixing code and custom tags with vanilla HTML, but I found AngularJS easy to use and relatively easy to understand. AngularJS version 2.0 comes out soon, but when that happens, I will likely switch to Aurelia. The Angular 2.0 syntax does not appeal to me, and Aurelia syntax is based on EcmaScript 6 which I want to explore anyway. The Aurelia creator was once even part of the Angular team, so there is that, too, if you like Angular 1.*.

Back End

Technically, Node.js is not a framework. It's a run-time environment. Express is the server framework in the MEAN stack though it just deals with routing. Nevertheless, I find myself thinking of Node as a framework since it sits on top of JavaScript much like Flask (a minimalist Python framework) sits on top of Python. If AngularJS is "batteries included", the Node.js philosophy is "go find your own batteries". I imagine this is great for teams that want to build everything custom or carefully choose components for every part of an application. But for me, since building a Web app requires lots of support code that everyone who builds a Web app has to write, I found myself wishing Node had more features. I could have easily used something like Sails.js, but since this was a learning project, I ultimately decided to "build my own batteries". Next time, I will just find a framework that fits the project.

Building batteries is educational in its own right, though for a production-ready app, I think the opposite may be a better approach for small teams. I once read you should never choose to build anything that is not core to your specific project. In other words, don't go building cryptographic hashing algorithms if that is not your specialty because it can and will blow up. This is probably why Node.js takes its particular philosophy and provides its package manager NPM to find what you need.

On the other hand, it's much easier to find app components if you already know what you should be looking for. I had to learn what I needed the hard way, though I suppose the resulting lesson stays with you longer.


Of all the concepts I learned during this project, test-driven development (TDD) and behavior-driven development (BDD) were the most profoundly fundamental lessons of them all. In short, build nothing without TDD/BDD! I found I prefer BDD for its syntax since it reads quite naturally. An example of a BDD test might be expect(thisArray).to.be.empty;. BDD makes it pretty clear what the code should be doing, and working with Mocha and Chai was a dream.

Writing test code is like writing an entirely separate program alongside the one you want to build. It takes lots of time, but from experience on this project, I can say the most difficult bugs in my code resulted from shortcutting the testing process. Once I took the time to go back, write proper tests, and refactor the code, everything broken then worked as it should. BDD makes it so much easier to spot mistakes and refactor your code without fear of breaking something somewhere else. Test, test, test, and be bold with your code!

Perhaps the most difficult issue to debug involved learning that Node.js caches the result of its "require" expressions. I was utterly baffled that part of my code ran fine on its own but flamed out spectacularly when run in concert with other code. Through trial, error, and loads of testing, I finally discovered Node.js caching was causing the problem and I could then design a workaround. I would have never even suspected Node was the problem without writing unit tests to eliminate all other possibilities.


Building a full-scale Web application solo, and for the first time, while simultaneously teaching myself the technologies involved, was a fun challenge that taught me many valuable lessons.

Just between you and me, I originally thought the Hacka_finder prototype would take me about 2 weeks to finish. Shows what I knew! Here we are a little over two months later with the app just now completed. Clearly it's good policy to always double or triple your estimate for how long you think it will take to finish a project. I have worked in industry long enough to know most people (myself included), when scoping a project, have a tendency to grossly underestimate the amount of time it takes to finish something. Always budget for the unknown where possible.

This project took a lot of work yet came with tremendous educational value. It was definitely worth the effort. If you decide to be MEAN and take your own journey to build a Web application from scratch, good luck to you. Just remember it takes longer than two weeks!