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How to protosketch

This post is a follow-on to the 18F blog post: “Sketching with Code: Protosketching”, which concludes:

If you are a leading a project, ask for a protosketch. If you are a developer, learn to protosketch. Create imagination-sparking moments, in the meeting. Give your team the freedom to play — with ideas, code and data. Minimize risk to your project and the American taxpayer by quickly testing ideas with the end-user in a vivid, clickable form. Develop and evaluate hypotheses on the fly. Protosketch to delight your team, your boss, and your customers.

Although not difficult, protosketching demands a definite “bag of tricks” that one should understand to rapidly create web-enabled spike solutions. Let’s dive a little deeper in.

Publicize your work with GitHub Pages

Your basic goal is to demonstrate possibilities rapidly. You can do this on your personal computer and have people crowd around it—but it is far more compelling to create an internet-accessible URL that your participants can view on their own devices. A durable URL that survives the meeting allows your work to be shown to others conveniently after the meeting.

GitHub Pages is a great way to to host static HTML pages. It costs $0 and has no bureaucratic overhead. This gives you a stable, publishable URL for your deliverable. As we will discuss below, by using JSON files to simulate a database, you can do a surprising amount of protosketching with static pages.

Incidental benefits to using GitHub Pages include the adoption of “open source process constraints”. It makes it easy to follow, for example, the 18F Open Source Policy, “from the first line.”

Leverage design for free using a framework

HTML is the basis of most web-enabled protosktetching. You probably need to understand HTML and CSS to protosketch rapidly. However, frameworks, such as Bootstrap and its many analogs, make it easy to look good quickly without deep knowledge of HTML design. In particular, such frameworks are responsive, meaning that sites using them work well on devices of different sizes and aspect ratios.

Although you may someday want to build a native mobile app, you will generally want to start with a mobile-friendly website instead.

jQuery API for mocking APIs quickly but dependably

One common thread in the projects being considered for 18F Consulting is a desire to integrate disparate data sources into a single application or dashboard-like interface. If feasible, a protosketch could and should connect to these data sources via an API to provide a near real-world demonstration of the desired product. Feasible within a protosketching meeting might mean “accomplishable in 30 minutes.”

You don’t need a working API if you can mock one out with static JSON. You can use jQuery to access the file or files to create a design that will be structurally similar to one that actually accessed an API or database. JavaScript allows you to tie any number of simulated datasources together into one HTML page.

As a program manager describes the data types of each source, just add samples to the JSON files. Soon enough, ask the program manager to refresh the page on their laptop or smartphone, and like magic they will see their product needs come to life. In many cases, it will be worthwhile to optimize JavaScript code to nicely render arbitrary JSON. In other words, the less your JavaScript knows about your data, the more flexibly you can sketch in sample data.

Making data malleable

The protosketcher should feel comfortable enough modifying sample data so that it feels “malleable”. Paul Graham, in an essay titled “Hackers and Painters”, wrote:

You should figure out programs as you’re writing them, just as writers and painters and architects do.

Realizing this has real implications for protosketching and software design in general. It means that programs and data should be plastic, by which we mean easily moldable and formable. As a programmer, you need to select tools that make this easy.

Although Graham was extolling the benefits of LISP in that essay, the same lesson applies to protosketching tools. Select tools and design code so that you feel comfortable not just expressing your own ideas about what should be built, but being an instrument for the program manager’s or end-user’s vision. JavaScript and mock APIs give us this freedom.

Render rapidly by using public or fake data

It is convenient to work publicly in open-source to avoid security issues, which means that we must use public or fake data, instead of private or secure data. For the purpose of making a compelling demo in a 1-3 hour time span, it is usually easy to find public data that gets the idea across, even if the final application will contain sensitive data. An example of fake text is the famous Lorem Ipsum text. Wikimedia Commons is a great source of photographs and visual designs that have clearly expressed, open licenses (or lack of licenses).

Running a server

Given the power of JavaScript, you can quickly build impressive demos with “fake” data using the JSON and jQuery API trick mentioned above. However, you may decide you need to implement a durable, changing data store. Such a data store cannot be easily realized with GitHub Pages. If you must run a small web server to have a changable data store, such as somenthing as simple as Ruby’s Sinatra or Python’s Flask, then localtunnel makes it very easy to provide a temporary public URL that points to your computer’s localhost.

You need not immediately abandon your JavaScript just because you have chosen to have a durable data store on a server. Merely use Flask or Sinatra only to implement the API that you have already mocked to provide basic create-read-update-delete functionality. If you have used Flask before, for example, this might take 20 minutes.

Heroku and similar application hosting platforms provides a more permanent and robust solution.

Theatrical devices

Protosketching is a form of coding athleticism–a performance art as a well as a compositional art. Don’t be ashamed to use a little showmanship.

Here are some of the techniques we have used:

  • For the Navy Reserve, our use of a durable URL let the Captain see the working prototype on his phone in the meeting.

  • A logo is easy to copy and cheap to add. A logo quickens simple content into a living application.

  • Utilize frameworks like Bootstrap that make it easy to look good quickly in a fully responsive way by leveraging other people’s design work.

  • Add just enough realistic data that the demo connotes exciting possibilities. We did this for GSA Human Resources department, and the result allowed them to think more clearly about what they wanted in the future.

  • Reuse wherever possible. In a one-hour challenge set by the Administrator of the GSA, we re-used our own Answers open-source project, which itself was forked from a Code for America’s Honolulu project. And it worked.

Motivation: Remember, you’re protosketching for the success of your project

Remember, the reason you are using a bag-of-tricks and theater is not to flim-flam anyone or prove how smart you are. Fundamentally we seek to de-risk a project by trying out ideas quickly, and that requires effective communication of those ideas to all stakeholders. It is our duty in any Agile, User-centered Design process to use any tool in our kit to accomplish this. Protosketching is a valuable kind of spike solution that lets you quickly get feedback from the user.

Appendix: A technical example

We exemplify some of the basic techniques mentioned in this article with an online, functioning prototype hosted completely free-of-charge with GitHub Pages. An open-source GitHub repo publicizes the code that implements it: protosketch-demo. The file explains a technique for running this site locally. Feel free to fork this repository if it seems like a good starting point for your own protosketching.

At the GitHub repository, you can find app.js, which is the heart of the application. At the end of this file you find an example of using JQuery to to read from a JSON file, which is analogous to a an API call:

$(document).ready(function() {
  $.getJSON("orders.json", function(data) {
    drawTable(data, "#current_order");

The file orders.json is remarkably simple, and clearly malleable enough to support any basic “database-backed website” situation.

    "id": 1,
    "date": "01\/12\/2015",
    "cost": "$15.54",
    "description": "Animal crackers and jelly beans"
    "id": 2,
    "date": "12\/01\/2014",
    "cost": "$12.34",
    "description": "Popcorn"
    "id": 3,
    "date": "11\/01\/2014",
    "cost": "$27.46",
    "description": "Pretzels, chips, and gummy bears"
    "id": 4,
    "date": "10\/01\/2014",
    "cost": "$15.20",
    "description": "Animal crackers and jelly beans"

The running demo is lightly styled using bootstrap, as you can see from the actual HTML file.

<link rel="stylesheet" href="" />

Bootstrap does require you to set up your DOM with certain conventions, which you can see in the full file.

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