2022-04-22 08:39:30 +03:00
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# Nix Store
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2022-04-19 04:53:39 +03:00
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A Nix store is a collection of *store objects* referred to by *store paths*.
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2020-11-24 15:38:12 +02:00
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Every store also has a "store directory path", which is a path prefix used for various purposes.
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There are many types of stores, but all of them at least respect this model.
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Some however offer additional functionality.
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2022-04-22 08:39:30 +03:00
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## A Rosetta stone for the Nix store.
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The design of Nix is comparable to other build systems, even programming languages in general.
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Here is a rough [Rosetta stone](https://en.m.wikipedia.org/wiki/Rosetta_Stone) for build system terminology.
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If you are familiar with one of these columns, this might help the following sections make more sense.
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generic build system | Nix | Bazel | Build Systems à la Carte | lazy programming language
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-- | -- | -- | -- | --
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data (build input, build result) | component | file (source, target) | value | value
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build plan | derivation graph | action graph | `Tasks` | thunk
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build step | derivation | rule | `Task` | thunk
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build instructions | builder | (depends on action type) | `Task` | function
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build | build | build | `Build` applied to arguments | evaluation
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persistence layer | store | file system | `Store` | heap
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(n.b. Bazel terms gotten from https://docs.bazel.build/versions/main/glossary.html.)
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Plenty more could be said elaborating these comparisons.
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We will save that for the end of this chapter, in the [Related Work](./related-work.md) section.
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