5 myth-busting reasons for choosing an automatic migration vs. a manual rewrite
There are still many myths out there surrounding software migrations. For starters,
there’s the perception that automation is just more trouble than it’s
worth. Though this may be true for really small and simple applications,
where the set up may not be worth the time, most conversion projects are large enough
that there are easily enough economies of scale. In these cases, the initial setup
might take several days, but then the migration tools can convert thousands of lines
of legacy code in just a fraction of the time that it would take to do so manually.
Performance expectations lead us to another false impression: software migration
can be completely automated. While it is true that there are amazing technical
solutions available that automate most of the work, there are still some aspects
that require human intervention. The most obvious is in the project management and
analysis areas, but there are also some code characteristics that simply cannot
be automatically upgraded. In many cases it’s just a matter of the cost of the implementation
not making the automation feasible, but in others a native translation may not be
possible due to the differences between the source and target platforms.
Finally, it appears that some fall for the preconceived belief that it’s just
plain better to start from scratch. It might be the case when you are dealing
with a somehow disposable system with useless, outdated functionality and no value
at all. Otherwise, to concur with this idea is to simply devalue all of the effort
and thought that was put into developing the application, willing to risk years
of business knowledge embedded in these systems. The truth is, a rewrite from scratch
implies a much more difficult task, even though some may claim that it is balanced
out by the fact that you can significantly reduce the total amount of code and fix
some of the imperfections that were present in the source application. But that’s
something you can also perform with an automated migration approach, and without
incurring in all that risk, time and cost.
Due to these misconceptions, valuable resources are wasted in projects that sometimes
just never get to see a successful ending. There’s no doubt that any software renewal
project isn’t a simple, overnight task, but a well-planned automated migration
can make the process comparatively painless. Besides, system upgrades are generally
worth the effort. Of course they involve time and expenses, but it provides savings
on the long run and a quick return on the investment, when your staff stops spending
all that time maintaining legacy systems and developing workarounds to compensate
for technology shortfalls.
So here are the main 5 myth-debunking reasons why an automatic migration is a far
better software modernization approach than a manual rewrite, based not only on
ArtinSoft’s own experience in migration projects but on all the customer and
industry analyst feedback and evidence gathered over the years.
It’s simple: many people just are not aware about the existence of automated
migration solutions. Case in point, on a survey made by Microsoft earlier
this year in the UK almost 40% of the respondents answered “False”
on the statement “There are tools to automatically convert Visual Basic 6.0
applications to Visual Basic .NET”. And that’s even when there
is a free, though rather limited, migration utility that ships with Visual Studio,
called the Microsoft Upgrade Wizard. So it was no surprise when more than 85% answered
equally when asked about Visual Basic 6.0 to C# conversion tools.
But these tools DO exist, and have been helping companies and developers for years
to leverage the investment embedded in legacy applications. Of course, as mentioned
before, 100% automation is normally not possible, though some people still expect
code translators to do all the work with no human interaction at all. There are
normally manual adjustments required to achieve compiling running code in the target
language, and even sometimes a real-world migration process is an iterative task
where tweaking the source codebase beforehand is also anticipated and recommended.
But technology has evolved to the point that there is hard to find a good reason
now to carry a software transformation effort based entirely on manual labor. And
fear of the unknown is just not a valid ground to discard potential time and money
Automatic migration technologies today are able to generate code of exceptional
quality, where you will not be able to tell if it was produced by a tool or by a
vastly experienced human developer. So there’s real value when you consider
that they allow handling the process even when the people involved are not highly
skilled in either the source or the target languages.
In the case of advanced VB6 to .NET migration products, extensive code analysis
can be performed to detect patterns that can be upgraded to more .NET-like, native
structures, making the output more readable and maintainable. This includes data
type enhancements, grammar pattern transformations and detailed code improvements.
On the other hand, an automatic migration does not fundamentally alter the architecture
of the original system, even if certain aspects like data access and some pieces
of GUI architecture do change. But the output of a good migration tool, which needs
to strike the right balance between automation and quality of the generated code,
is ready for application enhancement and evolution. At least in the case of ArtinSoft’s
Visual Basic Upgrade Companion (VBUC), you will be left with native VB.NET or C#
code, with no dependencies on third-party runtimes, plus the business knowledge
that was present in the original application gets completely preserved, including
all comments. This allows taking advantage of the new technologies available in
the .NET Framework, and eases the subsequent development and maintenance efforts.
The VBUC employs best programming practices, but it even has the ability to be extended
and customized, which allows generating code that adapts to specific requirements,
be it corporate policies or personal styles and preferences, increasing even further
the percentage of automation. And even in the worst case scenario, where you still
need to rewrite a certain piece of the application after the automated migration
phase, the end result will always be a fraction of the total cost and time. This
leads us precisely to the next points.
When dealing with projects related to business applications, in the end it is all
about money. So one cannot justify automatic migration based solely on technology
itself, but on cost savings, and when we look at this variable there are several
dimensions. The most obvious is the cost of the actual upgrade process, where it
can be said based on experience that an automatic migration can be done at 20% of
the cost of a manual rewrite. And most of that expenditure is due to testing and
fine tuning of the application on the new platform. The graph below reflects the
feedback from one of ArtinSoft’s customers, who concluded that an automatic
migration using the Visual Basic Upgrade Companion yielded 80% savings when compared
to a rewrite (and 60% savings when compared to a migration using another tool).
Then there’s also other savings with this approach that must be considered.
Take for example the training of end users. Since the application that results from
an automatic migration is 100% functionally equivalent to the original one, it is
not necessary to retrain them. With a rewrite, chances are that the output is not
going to be so familiar, unless you manage to follow an algorithmic approach like
the one employed by sophisticated automatic migration technologies. In some cases,
these retraining costs can be enormous. For example, another of our customers estimated
that its system would have required a 6 weeks training time, for 3000 users.
All in all, using technology is viable as long as it helps reducing the overall
effort. Even more in times of economic uncertainty, where it is crucial to save
up on scarce, valuable resources. So minimizing the investment when evolving the
infrastructure is definitely a must, and automation is certainly a good way of doing
Since Time is Money, this has a close relationship with the preceding point. Normally,
a legacy renewal project is a daunting task, but a migration tool can perform a
very large part of the work automatically, in a fraction of the time and using much
less resources. This can be better demonstrated by means of real-world examples.
Using the same instance of the customer above who compared application renewal solution
costs, the following numbers just speak for themselves; a manual rewrite for this
highly complex application was estimated to take 18 months, involving key personnel
from various departments, while a migration with the VBUC required the allocation
of much less resources for only 6 months.
One of our published
case studies, featuring Banamex, one of the largest Mexican financial institutions
and part of Citigroup, shows how they opted for an automatic migration with the
VBUC because of the shorter migration lifecycle it offered, which in turn helped
protect their market position. After an extensive analysis it came out as the most
cost-effective solution, when compared to the other options they were evaluating
in order to reduce the effort and investment.
Banamex considered rewriting 124 of their business critical VB6 applications, comprised
by a total of more than 5,000,000 lines of code, and estimated that at least 175
and up to 185 developers would need to be involved in the project for a period of
6 years, in addition to the resources required to manage and coordinate the normal
maintenance of these systems in the meantime. In contrast, using the VBUC allowed
less than half that amount of resources to complete the job in just 12 months.
Finally, there’s another
success story involving Vertex Financial Services in the UK, who migrated
one 616,000 lines-of-code application from VB6 to C#. Being in such a competitive
industry, they definitely needed to accelerate the time to market of their renewed
application, in order to meet the next product release. And they accomplished that
by using the Visual Basic Upgrade Companion instead of rewriting the application
Additionally, it must be noted that the above results were achieved using previous
versions of the tool. The latest release is definitely much more powerful, allowing
Finally, it is a well-known truth that, by nature, human activities are prone to
mistakes. Add the fact that legacy applications and all the changes made to them
during the years are not always well documented, and that the original developers
sometimes are no longer available, and you have a very high risk of business knowledge
loss when performing a manual rewrite. Plus there is always some level of uncertainty
involved, which makes costs and project timelines difficult to keep under control.
An automatic migration process leverages capital investment made in business applications.
That is, all customizations and business rules will be preserved in the migrated
system. Plus, as explained before, this approach provides a much faster renewal
lifecycle, and with minimal organizational disruption, which helps ensuring time
to market that can provide organizations with a valuable competitive advantage.
So it is a proven fact: using automated migration tools as part of an overall software
renewal initiative is the most viable way to leverage the current investment in
legacy applications and move them to the latest platforms. The technology available
today in that field can produce outstanding results in terms of cost and time savings,
risk avoidance and generated code quality.
Unfortunately, there are still many misconceptions surrounding automatic migration.
But many have already discovered how this approach constitutes the most cost-effective
alternative for legacy transformation projects indeed, and the word is starting
to spread. Which is really positive, since myths can only exist as long as the truth