inaka

Latest blog entries

/
IKJayma

IKJayma: A simple iOS Networking Library

Jul 21 2014 : Tom Ryan

/
Become an Erlang Cowboy and tame the Wild Wild Web - Part I

Erlang: From zero to coding a commenting system

Jun 23 2014 : Federico Carrone

/
Implementing a simple Rest Client in Android

How to create a simple Rest Client in Android

May 19 2014 : Henrique Boregio

/
Assisted Workflow: a CLI tool to speed up simple git workflows

Introducing the assisted_workflow gem, a cli tool with useful commands to integrate a simple git workflow with the story tracker and github pull requests

Mar 25 2014 : Flavio Granero

/
Cleaning Up Your GitHub Tree

How to clear all those stray branches

Feb 21 2014 : Pablo Villar

/
Friday Talks at Inaka

Lunch together, talk together

Dec 20 2013 : Inaka Blog

/
RubyConf Argentina 2013

Inaka represents at RubyConf 2013

Dec 18 2013 : Inaka Blog

/
Bounce Rate Bare-Bones Basics

An overview of bounce rate in broad strokes

Dec 05 2013 : Inaka Blog

/
Paintball: Inaka’s End-of-the-Year Party

Welts and bruises bring Inaka together

Nov 22 2013 : Inaka Blog

/
Inaka Product Review: Connection Minder

Making networking personal again

Nov 19 2013 : Inaka Blog

/
Canillita - Your First Erlang Server

Learn Erlang by example creating a simple RESTful server

Nov 06 2013 : Fernando "Brujo" Benavides

/
Landing Page Basics: What, How, and Why

The importance of a well-built landing page

Oct 29 2013 : Inaka Blog

/
Navigating Open Source Licensing

A comparison of common open source licenses

Oct 17 2013 : Inaka Blog

/
Git: Not Just for Devs

Sharing the Git love

Oct 07 2013 : Inaka Blog

/
Inaka Product Review: Go Dish

Go Dish brings good deals on good food

Oct 01 2013 : Inaka Blog

/
Reconsidering the Big Launch

Why big launches often disappoint, and what to do instead

Sep 23 2013 : Inaka Blog

/
Inaka Product Review: Whisper

Share secrets and meet new people with Whisper

Sep 16 2013 : Inaka Blog

/
Inaka Product Review: Ombu

Ombu combines the best of Bump and Scan to make sharing easy

Sep 11 2013 : Inaka Blog

/
Digitized Halloween Costumes

Morphsuits and Digital Dudz at your fingertips

Sep 09 2013 : Inaka Blog

/
7 Tactics to Build an App Without a Technical Cofounder: Part 3

Focusing on user experience through design

Sep 06 2013 : Inaka Blog

/
From Erlang to Java and Back Again: Part 1

My experience creating a Java/Erlang OTP application

Sep 05 2013 : Fernando "Brujo" Benavides

/
7 Tactics to Build an App Without a Technical Cofounder: Part 2

A realistic look at costs and business relations

Aug 30 2013 : Inaka Blog

/
7 Tactics to Build an App Without a Technical Cofounder: Part 1

Understanding the tools and processes of app development

Aug 28 2013 : Inaka Blog

/
Second-Screen App Round-Up

A round-up of network agnostic, network-based, and show-based apps

Aug 27 2013 : Inaka Blog

/
iOS Auto Layout

A review of Apple's Auto Layout technology

Aug 23 2013 : German Azcona

/
Core Data One-Way Relationships

Common design patterns in iOS applications

Mar 06 2013 : Tom Ryan

/
Everyday Erlang: Quick and effective caching using ETS

Using ETS for effective caching in Erlang

Mar 05 2013 : Marcelo Gornstein

/
Don't Under-Think It: SQL vs NoSQL

The effect of database choice on 'technical debt

Feb 26 2013 : Chad DePue

/
Erlang Event-Driven Applications

A thorough how-to on using events

Jan 21 2013 : Marcelo Gornstein

/
Don't Under-Think It: Making Critical Decisions When Building an iOS Application

How a few up-front decisions can make or break an app

Dec 06 2012 : Chad DePue

/
Some Erlang Magic for Beginners

Erlang tricks for beginners

Dec 03 2012 : Fernando "Brujo" Benavides

/
Inaka:Pong - DIY Sport

How to play Inaka:Pong, a new sport

Dec 03 2012 : Fernando "Brujo" Benavides

/
Every-day Erlang: Handling Crashes in Erlang

Handling crashes when calling gen_server:start link outside a supervisor

Nov 29 2012 : Marcelo Gornstein

/
Inaka Friday lunches

Team building at Inaka

Nov 02 2012 : Chad DePue

/
Inaka is a proud sponsor of Erlang DC

The largest Erlang event on the East Coast

Oct 23 2012 : Jenny Taylor

/
Inaka proud to be a sponsor of RubyConf Argentina

The largest Ruby event in South America

Oct 23 2012 : Jenny Taylor

/
Inaka client Ming.ly featured on LifeHacker

Big press for the Heroku-powered Rails-based Gmail plugin

Feb 28 2012 : Chad DePue

/
Scaling Erlang

Scale testing a sample Erlang/OTP application

Oct 07 2011 : Fernando "Brujo" Benavides

/
Memory Management Changes in iOS 5

A review of Apple's new ARC technology

Sep 05 2011 : German Azcona

/
My Year of Riak

Thoughts on using Basho's Riak database in production.

Aug 25 2011 : Chad DePue

/
Don't Under-Think It: Making Critical Decisions When Building an iOS Application

Chad DePue, Dec 06 2012

Getting started

When we were approached about building Whisper, my first thought was that this would be a great opportunity to apply a lot of my philosophy of app building. They had an incredibly smart founder, a really good idea, and funding. What they didn't have was a technical team. This is the type of project where our team shines. What follows here is an attempt to generalize some of the decisions we made. One was sufficiently painful enough that I wrote a summary and then decided to make it a second post. The rest are generally applicable to lots of applications and projects.

First Technology Decision - Ruby vs Erlang

Our team has a lot of experience with Ruby, Erlang, Scala, and C#. We only seriously considered Ruby and Erlang for this project. In the end, we went with the Hybrid model - Rails for Admin/Backend, Erlang for API. This turned out to be a great decision, as we're in the top 10% of traffic for all mobile apps with only a handful of servers. Was it a good decision to build a hybrid system with Erlang as the front line? YES. There are lots of good technologies out there, and you don't have to use either of these - but I'm a big fan of using the right tool for the job, and both Rails and Erlang/OTP have their place.

Second Technology Decision - Real-time sockets

We debated adding a special socket for deletes. The reason for this was we wanted to be able to remove inappropriate or hateful content without waiting for a device to refresh. This turned out to be an incredibly powerful channel that we now use for all sorts of things aside from deleting Whispers -- Metadata updates, connected user counts, deciding whether a user is connected and should get a push notification or a more powerful real-time socket update, determining activity, and more. After this experience, and with the ease of creating a socket channel in Erlang, I don't want to build another web application without including this "backchannel". Was it a good decision to implement a real-time channel in addition an HTTP/JSON API? YES.

Third Technology Decision - NoSQL vs SQL

For this application, we decided to use Riak, NoSQL database that has become more popular in the past year, because we expected a lot of users and a lot of Whispers. We decided that the additional up-front cost of Map/Reduces would be OK because we could really scale to dozens of Riak servers and Terabytes of Whisper data. This was not the case, and we'll cover what happened with Riak in a second post like I mentioned in the introduction. Was it a good decision to use Riak? Cue the ominous music and stay tuned...

Fourth Technology Decision - Security

We spent a lot of time thinking about device security and ways to prevent spam, jailbroken devices, fake users, and more. Should we build "banned users" into the app? Should we build filters for text content? Should we have multiple classes of users - trusted and untrusted? After months of operation, I can say:

  • Extra time up-front to ensure algorithmic rigor always pays off. Defenses we thought would be useful, such as authenticating all requests, requiring SSL, and others we can't mention here -- though they took a bit more time at the start -- have been incredibly useful.
  • Extra time on ontology is NOT worth it. By that, I mean classes of users, admin levels, etc. Until you SEE how people will use an app, behavior is incredibly hard to predict; and some of our up-front user segregation machinations were useless.

Fifth Technology Decision - Dials and Knobs

I have a forthcoming post about software designs, and what separates successful projects from unsuccessful ones. One of the major ways I can tell a team is professional and serious about building a successful app is when they don't come in with a lot of settings. A technology project's odds of success are inversely proportional to the number of customizable settings in the first version of that product.

In fact, I'm going to pause for effect here.

A technology project's odds of success are inversely proportional to the number of customizable settings in the first version of that product.


Whisper resisted for weeks the idea of adding even a settings page. We finally HAD to add one as Apple asked us to allow username customization, so we did so. Contrast this to many of the proposals I get each week with 20 to 25 ways to configure e-mail alerts and push notifications. Quite honestly, no iPhone carrying human has the emotional and mental bandwidth to think deeply about your alert preferences, and that is one of the reasons I'm not cynical about humanity's prospects. Do we need a lot of customizable settings for the first version of our app? The answer is always NO.

And Finally, The Most Important Decision - How much do I trust this team?

The client team in LA had wireframes and ideas for the app along with a great designer. But how much did they trust us? Do we focus on a perfect specification and an iron-clad contract down to the last penny and week? That puts a huge burden on up-front requirements gathering. And it focuses our relationship on a piece of paper. My favorite lawyer often says in the course of drafting bizdev agreements between large entities, "This piece of paper is worth nothing if the two parties in this room aren't committed to the relationship." A good contract is important, that's not up for debate. We work hard to make clear, concise contracts. But we work harder to be committed to the relationship. A scope of work is similar. We work HARD to build accurate estimates around projects, but we always remember that we're not locking ourselves into a fixed vision of an app before we've seen it in our hands.

In this case, we decided to build a scope of work from the wireframes as a target for our development effort. This is most useful because it gives us a sense of what the app is going to take to get it done. Then we basically throw it away after putting every task in that document into Pivotal Tracker. Pivotal becomes our Truth.

Fast forward to a few weeks later, after we had a prototype in-hand -- we threw out two MAJOR components we thought were critical to the first version. We didn't spend two seconds thinking about renegotiating a contract -- we just kept iterating.

Was an initial estimate enough to make a go/no-go decision? Yes. Did we know within 10% what our costs will be? No. In fact, we didn't know what the winning product was until we had built it. But was it a good decision to trust each other without knowing exactly where we were headed? As Whisper is currently the fastest growing social media app in the app store, I'd say YES.

Contact Us

Follow Chad On Twitter