What is a Legacy Application?

Some business applications just chug on, from day to day, year to year. They don’t blow-up, they don’t slow down, they just keep on going. Someone on your staff, Doug?, knows where to give them a bit of a tap and tune every now and them – a bit like you and your first car. Mine was a ’63 Morris Major Elite and there was nothing that 5L of oil and a whack to the starter motor wouldn’t fix.

One day you realise that the application has been running faithfully for a few years and the company that developed it for you isn’t around anymore. You ask around your company and find out that everybody knows how to use the application but they don’t really understand it in detail. You find that the tap and tune is being done by the networks guy reading from some instructions left by Doug who moved on a while ago.

That’s when you know you have a legacy application!

Don't Panic!

First of all, don’t panic!

This isn’t necessarily the end of the world. It’s been running fine for years, right? If it was troublesome or wasn’t performing a useful function it would be gone by now.

A legacy application isn’t in itself a bad thing as long as you are aware of any risks or limitations it may be putting on your business.

It’s just the odds are getting shorter that one day it will blow up, the whack to the starter motor won’t work anymore or a need to introduce change to the application will arise. So you need to plan for that day.

Assess

Firstly you need to know what you up against – what are the risks, how much time do you have and what help do you have in case of trouble.

Look at what risks there from your business point of view:

• How dependent is your business on the application?
• What business processes rely on it.
• Do you understand how the application works, what business rules and processes it uses or is it a bit of a black box?
• How easily can it be changed when your business requirements change or do you have to “work around” it?

You should also consider technology-based risks:

• How likely is it that something will go wrong?
• Are you stuck on unsupported hardware and software?
• Are you experiencing or about to experience bottlenecks and capacity problems?

Then look at your support options – who do you call.

• Is the original vendor still available, are they interested, how much do they cost?
• Are you dependent on a contractor or employee?
• Do you own and have access to the source code?
• Is the application easy to fix and modify or is it a bit of a mess?
• How quickly could I obtain support when I need it.

Plan

Now you have an understanding of the risks around your application and the likely impact on your business you can put together your plan to deal with it.

The main aim for the plan is to keep control and do things on your own terms, otherwise you’re heading for dangerous territory. Here are a few simple pointers to guide your planning:

• You have a lot of options; don’t go straight to the rewrite.
• If you have time use it, better to do things gradually than the big bang approach.
• Get help, you will need technical advice and support to identify the best way forward.

Of course situations like these vary hugely in both business and technical terms so there is no predefined solution but a good approach is to limit or reduce the functionality and your dependence on the application over time.

• Add new functionality around the application instead of extending it and integrate with workflows and services.
• Decouple business logic from the application, migrating it to a new application architecture. Then it’s available not only to the legacy applications but new applications can be built around it as required.
• Replace existing functions and modules with new application architecture.

The when the time comes to decommission the remaining application’s functions you have reduced the effort required and have a proven application architecture in place.

Of course the option is to leave the application as it is. Just make sure the application is thoroughly understood and documented.

In all cases you need to have a reliable support partner in place who can monitor and maintain the application to safeguard your business.

You can talk to us

Attain IT assists customers by offering an Applications Assessment.

We have been doing this for a long time and know that good results need a combination of strong commercial understanding, human change management awareness and strong architectural and technical skills.

We’ll work with you to conduct the Assessment and together we’ll determine an approach to management of your legacy application which makes sense for your business.

With skills in integration, application development, application maintenance and support, reporting and business intelligence as well as database infrastructure and middleware, we can give valuable insight to assist your strategy formulation.

Speak to Attain IT today. We’ll discuss the particular requirements of your business and the unique scenario regarding your application and its support. Then we’ll assist you to build a plan to support the business, manage risk and control cost which sits well with your overall business and IT strategy.

Attain IT offers pragmatic solutions, quality technical services and a trusted long term partnership.