A sufficiently detailed spec is code

#1

Post by signa11 » Thu, Mar 19, 2026, 2:23 AM UTC

A sufficiently detailed spec is code
haskellforall.com

Re: A sufficiently detailed spec is code

#2

Post by measurablefunc » Thu, Mar 19, 2026, 3:43 AM UTC

I agree with the overall structure of the argument but I like to think of specifications like polynomial equations defining some set of zeroes. Specifications are not really code but a good specification will cut out a definable subset of expected behaviors that can then be further refined with an executable implementation. For example, if a specification calls for a lock-free queue then there are any number of potential implementations w/ different trade-offs that I would not expect to be in the specification.

Re: A sufficiently detailed spec is code

#3

Post by notepad0x90 » Thu, Mar 19, 2026, 3:57 AM UTC

I agree to this, with the caveat that a standard is not a spec. E.g.: The C or C++ standards, they're somewhat detailed, but even if they were to be a lot more detailed, becoming 'code' would defeat the purpose (if 'code' means a deterministic turing machine?), because it won't allow for logic that is dependent on the implementer ("implementation defined behavior" and "undefined behavior" in C parlance). whereas a specification's whole point is to enforce conformance of implementations to specific parameters.

Re: A sufficiently detailed spec is code

#4

Post by ranyume » Thu, Mar 19, 2026, 3:57 AM UTC

I tried myself to make a language over an agent's prompt. This programing language is interpreted in real time, and parts of it are deterministic and parts are processed by an LLM. It's possible, but I think that it's hard to code anything in such a language. This is because when we think of code we make associations that the LLM doesn't make and we handle data that the LLM might ignore entirely. Worse, the LLM understands certain words differently than us and the LLM has limited expressions because of it's limits in true reasoning (LLMs can only express a limited number of ideas, thus a limited number of correct outputs).

Re: A sufficiently detailed spec is code

#5

Post by cheevly » Thu, Mar 19, 2026, 4:06 AM UTC

[dead]

Re: A sufficiently detailed spec is code

#6

Post by charcircuit » Thu, Mar 19, 2026, 4:08 AM UTC

This articles ignores that AI agents have intelligence which means that they can figure out unspecified parts of the spec on their own. There is a lot of the design of software that I don't care about and I'm fine letting AI pick a reasonable approach.

Re: A sufficiently detailed spec is code

#7

Post by rdevilla » Thu, Mar 19, 2026, 4:10 AM UTC

I think it's only a matter of time before people start trying to optimize model performance and token usage by creating their own more technical dialect of English (LLMSpeak or something). It will reduce both ambiguity and token usage by using a highly compressed vocabulary, where very precise concepts are packed into single words (monads are just monoids in the category of endofunctors, what's the problem?). Grammatically, expect things like the Oxford comma to emerge that reduce ambiguity and rounds of back-and-forth clarification with the agent.

The uninitiated can continue trying to clumsily refer to the same concepts, but with 100x the tokens, as they lack the same level of precision in their prompting. Anyone wanting to maximize their LLM productivity will start speaking in this unambiguous, highly information-dense dialect that optimizes their token usage and LLM spend...

Re: A sufficiently detailed spec is code

#8

Post by [deleted] » Thu, Mar 19, 2026, 4:13 AM UTC

charcircuit wrote: post #6

This articles ignores that AI agents have intelligence which means that they can figure out unspecified parts of the spec on their own. There is a lot of the design of software that I don't care about and I'm fine letting AI pick a reasonable approach.

[deleted]

Re: A sufficiently detailed spec is code

#9

Post by gizmo686 » Thu, Mar 19, 2026, 4:17 AM UTC

notepad0x90 wrote: post #3

I agree to this, with the caveat that a standard is not a spec. E.g.: The C or C++ standards, they're somewhat detailed, but even if they were to be a lot more detailed, becoming 'code' would defeat the purpose (if 'code' means a deterministic turing machine?), because it won't allow for logic that is dependent on the implementer ("implementation defined behavior" and "undefined behavior" in C parlance). whereas a sp…

Even programs are just specifications by that standard. When you write a program in C, you are describing what an abstract C machine can do. When the C compiler turns that into a program it is free to do so in any way that is consistent with the abstract C machine.

If you look at what implementions modern compilers actually come up with, they often look quite different from what you would expect from the source code

Re: A sufficiently detailed spec is code

#10

Post by systemsweird » Thu, Mar 19, 2026, 4:18 AM UTC

charcircuit wrote: post #6

This articles ignores that AI agents have intelligence which means that they can figure out unspecified parts of the spec on their own. There is a lot of the design of software that I don't care about and I'm fine letting AI pick a reasonable approach.

Exactly. The real speed up from AI will come when we can under specify a system and the AI uses its intelligence to make good choices on the parts we left out. If you have to spec something out with zero ambiguity you’re basically just coding in English. I suspect current ideas around formal/detailed spec driven development will be abandoned in a couple years when models are significantly better.