Legacy tech: Playing the infinite game

With technology moving in dog years, that means there are a lot of “legacy” dependencies - everywhere. While the prospect of addressing “legacy” or “end of life” technology can appear scary at first, the reality is that for most vendors who have been around long enough to penetrate a market with a mature product, these terms are a regular part of their vocabulary.

The only responsible way to upgrade technology is slowly and methodically. And in the meantime, risk mitigation is the name of the game.

Digging in

Mature technology companies tend to upgrade their stacks like so:

This is called the strangler fig pattern. It is methodical. It is consistent. It is reliable. It is often slow. So very slow.

Oh, and one more thing. There’s often no real “finish” line.

Let’s compare to the real world

Houses are typically renovated piece by piece, room by room - new strangling out old over years. Some rooms or foundational infrastructure remain original regardless. And whatever code they were built to at that original time is grandfathered in.

This 3-mile-long boardwalk at a beach town near my house has been getting strangled by a new boardwalk, block by block, for nearly a decade.

What have we learned?

These types of upgrade projects often take much longer than the initial construction. And note how they are so piecemeal that old infrastructure is never totally eradicated; By the time everything is new, something is old again. The old and new must find a way to coexist in harmony.

What about the risk inherent in the old technology?

From a delivery efficiency and security perspective, this risk of legacy technology is often dealt with by monitoring and managing pointed, known risks, then mitigating them to the best extent possible. Returning to the boardwalk example, if one plank in particular is so degraded that it represents an outsized danger to pedestrians, that one plank can be replaced.

The digital world is no different than the real world in this regard. Remember to be pragmatic and patient out there!