A while ago I had lunch with my wife in a Toronto midtown restaurant called “Grazie”. As I was perusing the menu, a small rectangle at the bottom attracted my attention. It read:
We strongly discourage substitutions. The various ingredients have been selected to complement each other. Substitutions will undermine the desired effect of the dish. Substitutions will slow down our service.
When I read it first, I filed it under ‘opinionated chef’ (as if there is any other kind) and also remembered another chef named Poppie from a Seinfeld episode, who opined on this topic thusly:
POPPIE: No, no. You can’t put cucumbers on a pizza.
KRAMER: Well, why not? I like cucumbers.
POPPIE: That’s not a pizza. It’ll taste terrible.
KRAMER: But that’s the idea, you make your own pie.
POPPIE: Yes, but we cannot give the people the right to choose any topping they want! Now on this issue there can be no debate!
Fast forward to 2013. This whole topic came back to my volatile memory as I was ruminating about what the cloud platform model means for web app developers. In the years before the cloud, we would carefully consider our storage solution, our server and client technology stack and other elements with an eye on how the application is going to be deployed. You wanted to minimize support and maintenance cost, administration headaches and also wanted to achieve economy of scale. A large web application is composed of components, and the economy of scale can be achieved if one architectural style is followed throughout, one database type, one web framework that supports components etc.
In this architecture, it is just not feasible to allow freedom for components to have a say in this matter. Maintaining three different databases or forcing three Web frameworks to cooperate is just not practical, even though these choices may be perfect for the components in question. The ‘good enough’ fit was a good compromise for consistency and ease of support and maintenance.
In contrast, a modern web application is now becoming a loose collection of smaller apps running in a cloud platform and communicating via agreed upon protocols. One of the key selling points of the cloud platform is that it is easy to write and publish an app and have it running within minutes. I am sure early successes are important for learning, and many apps will be tactical and time-boxed – up for a couple of months, then scrapped. But a much more important aspect of the new architecture to me is the opportunity to carefully curate the components of your federated application, the way an opinionated chef selects ingredients for a gourmet pizza.
- You have the freedom to select the right database, server and client side that is the best fit for the problem that a single app is trying to solve. You can write computationally intensive app in Java or Scala, write front end app with a lot of I/O and back-and-forth chatter in Node.js, and another in Django or RubyOnRails because you simply like it and it makes you more productive. You don’t have to use whatever has been chosen by the entire team even though it does not fit your exact needs.
- You then have the freedom to compose your federated application out of individual apps cooperating as services, each one optimized for its particular task. As I said earlier, this would have been prohibitively expensive and impractical in the past, but is now attainable for smaller and smaller providers. The cloud platform has subsumed the role of the economy of scale vehicle that was previously required from large applications deployed on premise.
The vision of the polyglot future has been already declared for programming languages by Dave Fecak et al and also for storage solutions by Martin Fowler. A common thread in both is ‘best fit for the task’. In the former, additional angle was employment prospects of polyglot developers, while in the latter was a caveat that polyglot persistence comes with the expense of additional complexity.
I think that my point of view is subtly different: in the cloud platforms, complexity of managing many different systems is mitigated by the fact that the platform is responsible for most of it. On the other hand, while CFOs are salivating over the prospects of slashed IT expenses in hosted solutions, I am more intrigued by another unexpected side-effect: using the right tool for the right job and using multiple tools within the same project is now attainable for smaller players. All of a sudden, an application running multiple servers, each using a different database type is trivially possible for even the smallest startups.
We will never be asked again to put cucumber on our pizza just because the team as a whole has decided so, even though we hate cucumber. Conversely, we CAN put cucumber just on our pizza even though the rest of the team doesn’t like it if works wonderfully in our unique combination. In the new world of cloud platforms, we can all make gourmet pizza-style applications, each carefully put together, each uniquely delicious, and each surprisingly affordable. The opinionated chef from Grazie now seems almost prophetic: in the cloud, we DO want to select various ingredients to complement each other, because substitutions will undermine the desired effect and slow down our service(s).
You can almost pass the restaurant’s menu as the white paper.
© Dejan Glozic, 2013