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--- a/doc/languages-frameworks/agda.section.md
+++ b/doc/languages-frameworks/agda.section.md
@@ -1,91 +1,178 @@
----
-title: Agda
-author: Alex Rice (alexarice)
-date: 2020-01-06
----
-# Agda
+# Agda {#agda}
 
-## How to use Agda
+## How to use Agda {#how-to-use-agda}
 
-Agda can be installed from `agda`:
-```
-$ nix-env -iA agda
-```
+Agda is available as the [agda](https://search.nixos.org/packages?channel=unstable&show=agda&from=0&size=30&sort=relevance&query=agda)
+package.
 
-To use agda with libraries, the `agda.withPackages` function can be used. This function either takes:
-+ A list of packages,
-+ or a function which returns a list of packages when given the `agdaPackages` attribute set,
-+ or an attribute set containing a list of packages and a GHC derivation for compilation (see below).
+The `agda` package installs an Agda-wrapper, which calls `agda` with `--library-file`
+set to a generated library-file within the nix store, this means your library-file in
+`$HOME/.agda/libraries` will be ignored. By default the agda package installs Agda
+with no libraries, i.e. the generated library-file is empty. To use Agda with libraries,
+the `agda.withPackages` function can be used. This function either takes:
 
-For example, suppose we wanted a version of agda which has access to the standard library. This can be obtained with the expressions:
+* A list of packages,
+* or a function which returns a list of packages when given the `agdaPackages` attribute set,
+* or an attribute set containing a list of packages and a GHC derivation for compilation (see below).
+* or an attribute set containing a function which returns a list of packages when given the `agdaPackages` attribute set and a GHC derivation for compilation (see below).
 
-```
+For example, suppose we wanted a version of Agda which has access to the standard library. This can be obtained with the expressions:
+
+```nix
 agda.withPackages [ agdaPackages.standard-library ]
 ```
 
 or
 
-```
+```nix
 agda.withPackages (p: [ p.standard-library ])
 ```
 
 or can be called as in the [Compiling Agda](#compiling-agda) section.
 
-If you want to use a library in your home directory (for instance if it is a development version) then typecheck it manually (using `agda.withPackages` if necessary) and then override the `src` attribute of the package to point to your local repository.
-
-Agda will not by default use these libraries. To tell agda to use the library we have some options:
-- Call `agda` with the library flag:
-```
-$ agda -l standard-library -i . MyFile.agda
-```
-- Write a `my-library.agda-lib` file for the project you are working on which may look like:
-```
-name: my-library
-include: .
-depend: standard-library
-```
-- Create the file `~/.agda/defaults` and add any libraries you want to use by default.
+If you want to use a different version of a library (for instance a development version)
+override the `src` attribute of the package to point to your local repository
+
+```nix
+agda.withPackages (p: [
+  (p.standard-library.overrideAttrs (oldAttrs: {
+    version = "local version";
+    src = /path/to/local/repo/agda-stdlib;
+  }))
+])
+```
+
+You can also reference a GitHub repository
+
+```nix
+agda.withPackages (p: [
+  (p.standard-library.overrideAttrs (oldAttrs: {
+    version = "1.5";
+    src =  fetchFromGitHub {
+      repo = "agda-stdlib";
+      owner = "agda";
+      rev = "v1.5";
+      sha256 = "16fcb7ssj6kj687a042afaa2gq48rc8abihpm14k684ncihb2k4w";
+    };
+  }))
+])
+```
+
+If you want to use a library not added to Nixpkgs, you can add a
+dependency to a local library by calling `agdaPackages.mkDerivation`.
+
+```nix
+agda.withPackages (p: [
+  (p.mkDerivation {
+    pname = "your-agda-lib";
+    version = "1.0.0";
+    src = /path/to/your-agda-lib;
+  })
+])
+```
+
+Again you can reference GitHub
+
+```nix
+agda.withPackages (p: [
+  (p.mkDerivation {
+    pname = "your-agda-lib";
+    version = "1.0.0";
+    src = fetchFromGitHub {
+      repo = "repo";
+      owner = "owner";
+      version = "...";
+      rev = "...";
+      sha256 = "...";
+    };
+  })
+])
+```
+
+See [Building Agda Packages](#building-agda-packages) for more information on `mkDerivation`.
+
+Agda will not by default use these libraries. To tell Agda to use a library we have some options:
+
+* Call `agda` with the library flag:
+  ```ShellSession
+  $ agda -l standard-library -i . MyFile.agda
+  ```
+* Write a `my-library.agda-lib` file for the project you are working on which may look like:
+  ```
+  name: my-library
+  include: .
+  depend: standard-library
+  ```
+* Create the file `~/.agda/defaults` and add any libraries you want to use by default.
 
 More information can be found in the [official Agda documentation on library management](https://agda.readthedocs.io/en/v2.6.1/tools/package-system.html).
 
-## Compiling Agda
-Agda modules can be compiled with the `--compile` flag. A version of `ghc` with `ieee` is made available to the Agda program via the `--with-compiler` flag.
+## Compiling Agda {#compiling-agda}
+
+Agda modules can be compiled using the GHC backend with the `--compile` flag. A version of `ghc` with `ieee754` is made available to the Agda program via the `--with-compiler` flag.
 This can be overridden by a different version of `ghc` as follows:
 
-```
+```nix
 agda.withPackages {
   pkgs = [ ... ];
   ghc = haskell.compiler.ghcHEAD;
 }
 ```
 
-## Writing Agda packages
-To write a nix derivation for an agda library, first check that the library has a `*.agda-lib` file.
+## Writing Agda packages {#writing-agda-packages}
+
+To write a nix derivation for an Agda library, first check that the library has a `*.agda-lib` file.
 
 A derivation can then be written using `agdaPackages.mkDerivation`. This has similar arguments to `stdenv.mkDerivation` with the following additions:
-+ `everythingFile` can be used to specify the location of the `Everything.agda` file, defaulting to `./Everything.agda`. If this file does not exist then either it should be patched in or the `buildPhase` should be overridden (see below).
-+ `libraryName` should be the name that appears in the `*.agda-lib` file, defaulting to `pname`.
-+ `libraryFile` should be the file name of the `*.agda-lib` file, defaulting to `${libraryName}.agda-lib`.
 
-### Building Agda packages
+* `everythingFile` can be used to specify the location of the `Everything.agda` file, defaulting to `./Everything.agda`. If this file does not exist then either it should be patched in or the `buildPhase` should be overridden (see below).
+* `libraryName` should be the name that appears in the `*.agda-lib` file, defaulting to `pname`.
+* `libraryFile` should be the file name of the `*.agda-lib` file, defaulting to `${libraryName}.agda-lib`.
+
+Here is an example `default.nix`
+
+```nix
+{ nixpkgs ?  <nixpkgs> }:
+with (import nixpkgs {});
+agdaPackages.mkDerivation {
+  version = "1.0";
+  pname = "my-agda-lib";
+  src = ./.;
+  buildInputs = [
+    agdaPackages.standard-library
+  ];
+}
+```
+
+### Building Agda packages {#building-agda-packages}
+
 The default build phase for `agdaPackages.mkDerivation` simply runs `agda` on the `Everything.agda` file.
 If something else is needed to build the package (e.g. `make`) then the `buildPhase` should be overridden.
 Additionally, a `preBuild` or `configurePhase` can be used if there are steps that need to be done prior to checking the `Everything.agda` file.
 `agda` and the Agda libraries contained in `buildInputs` are made available during the build phase.
 
-### Installing Agda packages
-The default install phase copies agda source files, agda interface files (`*.agdai`) and `*.agda-lib` files to the output directory.
+### Installing Agda packages {#installing-agda-packages}
+
+The default install phase copies Agda source files, Agda interface files (`*.agdai`) and `*.agda-lib` files to the output directory.
 This can be overridden.
 
-By default, agda sources are files ending on  `.agda`, or literate agda files ending on `.lagda`, `.lagda.tex`, `.lagda.org`, `.lagda.md`, `.lagda.rst`. The list of recognised agda source extensions can be extended by setting the `extraExtensions` config variable.
+By default, Agda sources are files ending on `.agda`, or literate Agda files ending on `.lagda`, `.lagda.tex`, `.lagda.org`, `.lagda.md`, `.lagda.rst`. The list of recognised Agda source extensions can be extended by setting the `extraExtensions` config variable.
 
-To add an agda package to `nixpkgs`, the derivation should be written to `pkgs/development/libraries/agda/${library-name}/` and an entry should be added to `pkgs/top-level/agda-packages.nix`. Here it is called in a scope with access to all other agda libraries, so the top line of the `default.nix` can look like:
-```
+## Adding Agda packages to Nixpkgs {#adding-agda-packages-to-nixpkgs}
+
+To add an Agda package to `nixpkgs`, the derivation should be written to `pkgs/development/libraries/agda/${library-name}/` and an entry should be added to `pkgs/top-level/agda-packages.nix`. Here it is called in a scope with access to all other Agda libraries, so the top line of the `default.nix` can look like:
+
+```nix
 { mkDerivation, standard-library, fetchFromGitHub }:
 ```
-and `mkDerivation` should be called instead of `agdaPackages.mkDerivation`. Here is an example skeleton derivation for iowa-stdlib:
 
-```
+Note that the derivation function is called with `mkDerivation` set to `agdaPackages.mkDerivation`, therefore you
+could use a similar set as in your `default.nix` from [Writing Agda Packages](#writing-agda-packages) with
+`agdaPackages.mkDerivation` replaced with `mkDerivation`.
+
+Here is an example skeleton derivation for iowa-stdlib:
+
+```nix
 mkDerivation {
   version = "1.5.0";
   pname = "iowa-stdlib";
@@ -101,6 +188,7 @@ mkDerivation {
   '';
 }
 ```
+
 This library has a file called `.agda-lib`, and so we give an empty string to `libraryFile` as nothing precedes `.agda-lib` in the filename. This file contains `name: IAL-1.3`, and so we let `libraryName =  "IAL-1.3"`. This library does not use an `Everything.agda` file and instead has a Makefile, so there is no need to set `everythingFile` and we set a custom `buildPhase`.
 
-When writing an agda package it is essential to make sure that no `.agda-lib` file gets added to the store as a single file (for example by using `writeText`). This causes agda to think that the nix store is a agda library and it will attempt to write to it whenever it typechecks something. See [https://github.com/agda/agda/issues/4613](https://github.com/agda/agda/issues/4613).
+When writing an Agda package it is essential to make sure that no `.agda-lib` file gets added to the store as a single file (for example by using `writeText`). This causes Agda to think that the nix store is a Agda library and it will attempt to write to it whenever it typechecks something. See [https://github.com/agda/agda/issues/4613](https://github.com/agda/agda/issues/4613).