Legacy Code. I never wrote it; everybody else did!
How many times have you waded through an ageing, decaying, tangled forrest of code and wished it would just die?
How many times have you heard someone say that what really needs to happen is a complete rewrite?
I have heard this many times, and, have uttered that fatal sentence myself.
But shouldn’t we love our legacy code?
Doesn’t it represent our investment and the hard work of ourselves and our predecessors?
Throwing it away is dangerous, because, before we do, we’ll need to work out exactly what it does, and we’ll need to tweeze out that critical business logic nestled in a deeply entangled knot of IF statements. It could take us years to do, and we’ll have to maintain two systems whilst we do it, inevitably adding new features to them both. Yes we get to reimplement using the latest, coolest programming language, instead of an old behemoth, but how long will our new cool language be around, and who will maintain that code, when it itself inevitably turns to legacy?
We can throw our arms in the air, complaining and grumbling about how we didn’t write the code, how we would never have written it the way it is, how those that wrote it were lesser programmers, possibly lesser humans themselves, but the code still remains, staring us in the face and hanging around for longer that we could possibly imagine. We can sort it out, we can improve it, we can make it testable, and we can learn to love our legacy code.