tagged by: evolutionary design
Is Design Dead?
For many that come briefly into contact with Extreme Programming, it seems that XP calls for the death of software design. Not just is much design activity ridiculed as "Big Up Front Design", but such design techniques as the UML, flexible frameworks, and even patterns are de-emphasized or downright ignored. In fact XP involves a lot of design, but does it in a different way than established software processes. XP has rejuvenated the notion of evolutionary design with practices that allow evolution to become a viable design strategy. It also provides new challenges and skills as designers need to learn how to do a simple design, how to use refactoring to keep a design clean, and how to use patterns in an evolutionary style.
May 2004
article
Schemaless Data Structures
In recent years, there's been an increasing amount of talk about the advantages of schemaless data. Being schemaless is one of the main reasons for interest in NoSQL databases. But there are many subtleties involved in schemalessness, both with respect to databases and in-memory data structures. These subtleties are present both in the meaning of schemaless and in the advantages and disadvantages of using a schemaless approach.
7 January 2013
infodeck
AssetCapture
Asset capture is a strategy for developing a StranglerApplication. You can think of many applications as managing a key set of assets. A payroll system looks after employees, a trading system looks after trades, a leasing system looks after leases. To gradually cut over to a new system, you can begin by identifying a subset of assets that you'll start with the new system. Often the best assets to start with are either simple assets (because they are quick to get going) or those that have needs that are particularly difficult to handle with the old system.
bliki
EvolutionarySOA
I don't delve too much into the cluttered world of SOA (ServiceOrientedAmbiguity), but I get this question often enough (in some form or other) to be worth a pontification.
12 September 2008
bliki
Seedwork
In the very earliest days of Object-Orientation, the OO advocates like me put a lot of attention into arguing in favor of reuse. Early on we talked about reusing of classes. Then we discovered that reusing individual classes, while it worked in some cases, didn't work so well elsewhere. So we got into reusable frameworks, which got us part-built applications of functionality.
11 September 2003
bliki
Evolutionary Database Design
by Pramod Sadalage and Martin Fowler
Over the last few years we've developed a number of techniques that allow a database design to evolve as an application develops. This is a very important capability for agile methodologies. The techniques rely on applying continuous integration and automated refactoring to database development, together with a close collaboration between DBAs and application developers. The techniques work in both pre-production and released systems.
January 2003
article
AbundantMutation
Any reader of my writings will know that I'm a big proponent of evolutionary design. Despite my enthusiasm for this approach, no technique is perfect and I'm just as happy to report its problems as I am its successes.
14 February 2005
bliki
DesignStaminaHypothesis
From time to time I have indirect conversations about whether good software design is a worthwhile activity. I say these conversations are indirect because I don't think I've ever come across someone saying that software design is pointless. Usually it's expressed in a form like "we really need to move fast to make our target next year so we are reducing <some design activity>".
20 June 2007
bliki
NoDBA
In many organizations, it's expected that any persistent data will be stored in relational databases that are managed by a central database management group. There are various reasons for such central control, usually centered around using IntegrationDatabases. Central data groups worry about keeping out malformed data, queries that can slow down important shared resources, and consistent data models across the enterprise.
Worthy these aims may be, but one consequence of them is considerable ceremony about storing data. I often hear complaints about change orders that take weeks to add a column to a database. For modern application developers, used to short-cycle evolutionary design, such ceremony is too slow, not to mention too annoying.
So application development groups tell me of using NoSQL databases to do an end-run around the DBAs. It helps that they are using a "mere datastore" here, not a "proper database". That way the DBAs can be kept out of the loop, often not told or happy to not care.
25 February 2013
bliki
TolerantReader
One of the benefits of using web services is that it helps you to decouple various parts of a system. People can work on separate code-bases with some degree of separation. Although you get some decoupling, you cannot eliminate the coupling completely because the services still have to communicate to each other through their interfaces. The sad thing is that many teams make this coupling much worse than it should be.
9 May 2011
bliki
