Technology strategy: a look back at 2015

A user from Mexico recently wrote to us asking which technologies we currently use for the Kerika software, since he was in the early days of planning his own ERP product and was impressed with the overall speed and responsiveness of Kerika.

The question was hard to answer with a simple email in part because we use several technologies, and because we are in the middle of considering some significant changes for 2016.

So, here’s an overview of the current state, with a future blog post to talk about what we are planning to change in 2016…

Our own server software:

All of our server software is written in Java.  That’s has worked well for us:

  • We have a lot of in-house expertise with Java (and none with PHP, Ruby, etc.).
  • Java is usually one of the first languages to be supported by other platform companies that decide to publish their APIs.
  • There is a rich ecosystem of open-source code, well-written blog posts and other knowledge sources that help us get our work done.

Open-source server software:

We use a few, well-established open source technologies on the back-end of Kerika:

  • We use the CometD protocol to provide real-time updates from the server to the browser client. CometD essentially works like a long-poll method, allowing for real-time updates to be pushed continuously from the server to the client without the client having to make new requests.  We could, and probably should, switch over entirely to Web Sockets but there are still older browsers out there that don’t support Web Sockets. Hence, CometD.
  • We use SOLR for our search engine. SOLR is an implementation of the Lucene search technology pioneered over a decade ago by Doug Cutting who has since gone on to do other great work in the software industry. SOLR is widely used by some very large SaaS services like Salesforce.
  • We use Jetty for our web servers.  Jetty is part of the Apache open-source projects, and is a well-established, robust web server that hasn’t given us any trouble in a long while. :-)
  • We use open-source OAuth for our direct signup.
  • We use the Java Spring and JBoss libraries for various features.
  • We use Log4J for error logging.
  • We use MySQL for our databases.

Platform Libraries

Given our close integration with Google and Box, we naturally use their Java SDK Libraries for authentication and file management.

We used to use Google Checkout, until Google yanked that service from the market (leaving us high-and-dry and more than a little pissed off…) as well as Google Contacts, until we realized this particular integration was scaring away potential users.

Client Software

All of our browser software is written in HTML5, which means a mix of (mostly) Javascript and (a little) SVG.

(Actually, the SVG is only used for the Whiteboards feature of Kerika. The rest is all Javascript and plain HTML.)

Open-source client software

The Javascript ecosystem is quite rich and well established, so there are a bunch of open source libraries we can make good use of:

  • JQuery is used a lot. A lot.
  • More recently, Backbone and Marionette have helped fill in the blanks left by JQuery.
  • The i18n.js library helps with internationalization, although we haven’t actually offered any language other than English so far, for the user interface.
  • Log4Javascript helps with error logging and debugging.
  • Bootstrap is used mainly for our website, to make it responsive on tablets and phones.

What changes in 2016?

Quite a lot, probably, but we haven’t finished doing our re-architecture planning.

For one thing, we are planning to use microservices a lot more to make our overall system architecture less monolithic, and we are also planning to use container technology to make deployments faster.

We might consider switching away from SOLR, which we never really mastered, to another search engine which we have more familiarity with, but haven’t made a decision on that either.


Bug, fixed: board descriptions in Internet Explorer 11

We found a bug that was causing problems for users who wanted to edit/update their board descriptions, using Internet Explorer. We fixed that.

In case you are wondering where the board description is found in the first place, here’s how you can edit it:

Click on the gear icon that appears on the top-right corner of every Task Board, Scrum Board or Whiteboard, and then chose the Settings tab:

Editing board descriptions
Editing board descriptions


By default, the board description field will be empty, naturally, but if you are one of the Board Admins (or the Account Owner), when you move your mouse over the Description field you will see a pencil icon appear (highlighted in red, above), and clicking on that will let you add a board description.

Adding a board description
Adding a board description


Board descriptions can be up to 180 characters long, and as you type the system will automatically let you know how many characters are left for you to type. (Yes, Twitter-style.)

Board descriptions are going to be very useful in the future as we make some changes to our user interface and search functions.

Kerika’s Templates

We offer a small selection of templates, covering a wide range of possible projects, to help our users get started with new boards — and, more importantly, to help introduce the concept of templates to folks.

Some of the templates we have on offer:

We experienced some performance issues related to these templates recently which we have fixed: as the total number of Kerika users grew, the number of people wanting to use the same templates grew somewhat faster than we had anticipated, so we needed to make some back-end fixes to make sure there wasn’t a slowdown in performance.


Bug, fixed: handling non-English characters

This is kind of annoying and embarrassing, but a while back a bug crept back into our code that made non-English characters appear as question marks.

Embarrassing because we have fixed this bug before. More than once.

This time around the bug crept back in while we were taking care of some other feature, and unfortunately it was one of our (Chinese-speaking) users who spotted it before we did.

Our own team is multilingual (3 languages) but we work almost exclusively using English, so this was one of those rare scenarios where we didn’t use a particular feature of Kerika and so developed a blind spot.

Sorry about that.  The good news is that the fix is retroactive: any non-English characters that you had previously entered will not appear correctly, without any work on your end.

Bug, fixed: holding down the Enter key while editing project descriptions

Thanks to one of our long-standing Kerika users (over in Gdansk, Poland) for spotting a bug that we have fixed: if you held down the Enter key for “too long” (which is kind of a vague description, we know) while editing a card’s description, some junky HTML text would appear:

Card description bug
Card description bug


It was an odd timing issue that we hadn’t noticed before. Thanks for helping us find this bug!