What Is Spec-Driven Development?

**SPEAKER_1** (0:00)
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**Viktor Farcic** (0:30)
Let's write it in five different languages. I'm just validating the idea and the design behind the idea and all that jazz.
And throw it away. Completely throwable. Something that would be unimaginable. Imagine kind of like five MVPs for a new product, not fully fleshed out with all the features, but kind of five MVPs. I never built it in less than a week, a month.
Teams take weeks, months to build an MVP, singular. I can build five in a day.

**Darin Pope** (1:05)
This is DevOps Paradox, episode number 357 What is spec-driven development?
Welcome to DevOps Paradox. This is a podcast about random stuff in which we, Darin and Viktor, pretend we know what we're talking about. Most of the time, we mask our ignorance by putting the word DevOps everywhere we can and mix it with random buzzwords like Kubernetes, serverless, CICD, team productivity, islands of happiness, and other fancy expressions that make us sound like we know what we're doing. Occasionally, we invite guests who do know something, but we do not do that often since they might make us look incompetent. The truth is out there, and there is no way we are going to find it. Yes, it's Darin reading this text and feeling embarrassed that Viktor made me do it. You're your host, Darin Pope and Viktor Farsic. So if you're writing code using AI, where you're just typing in prompts and then fixing hallucinations, you're doing it wrong. Not a bad place to start. That's called vibe coding, but that's not where you want to stay.
Spec-driven development, however, might be the next step, but even that can be questionable. Viktor, how did you start up your process when you started with AI? Did you just go from specs from day one, or what were you doing?

**Viktor Farcic** (2:36)
Specs from day one.
The reasons are very simple for that. I hit specs before AI. But I don't fully understand what's changed.

**Darin Pope** (2:46)
So even if you were just trying to come up with an idea, you would have specs? You would go that far versus just guess? See, you spend way too much time planning than I do.

**Viktor Farcic** (2:56)
Just to be clear, before AI, depending on whether I work in a team or solo, I would always have specs. But sometimes specs could be in my head.

**Darin Pope** (3:09)
So you had an idea.

**Viktor Farcic** (3:11)
It's always more than an idea. I'm not kind of like, yeah, I have an idea. I have no idea. Should it be Go or should it be Python? Are we running it in cloud or am I running it below my desk? Kind of, I never tried to do anything so unprepared. There is always more than idea. There is more than I'm going to create, I don't know, DevOps agent. What will it do? I don't know. Where it will run? I don't know. I mean, it might start like that.
But it progresses further than that before I start writing code. So there is always spec. What we should talk about is how detailed it should be. And in some cases, for some people, maybe there is no spec, kind of. I literally don't know what I'm going to do. But then it reminds me, you know, I don't know whether there is still in Google, at least before, if not still, there was a I'm feeling lucky button.
Maybe some people do it like that, I don't.

**Darin Pope** (4:20)
Well, that's sort of the scenario I was laying out, to where you start writing something with a prompt, it comes back, oh, yeah, that's not right. So you update your prompt, and it's not right, and you keep going in this cycle until eventually you run out of context, or you get compacted and you lose things. It's like playing whack-a-mole.
That's what we don't want to do.

**Viktor Farcic** (4:41)
Imagine if you replace that agent with a person. We're going to the era before AI. How would you do it? Would you say just kind of, hey, let's say you and me work on a project, and you have some rough idea what that project is, and you tell me, Viktor, let's work on a project. What is it? I don't know. I'm not telling you.