Docs: recommend installing uplc-ghc via ghcup

The ghcup channel is live and release 9.6.166.1 is published, so replace the
'coming soon' placeholder with the real instructions and make ghcup the
recommended install method; building from source stays as the alternative.
Point the tutorial and how-to/use at the PATH-installed uplc-ghc and pin the
ghc-plinth-plutus commit matching the release.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: hsyl20

how-to/build.md

@@ -5,12 +5,45 @@ permalink: /how-to/build/
 This guide explains how to get `uplc-ghc`, the
 [Plinth standalone compiler]({% link explanation/standalone-compiler.md %}).
 
+The recommended way is to [install a released binary via
+ghcup](#installing-via-ghcup). [Build from source](#building-from-source) when
+you work on the compiler itself, or when no binary distribution covers your
+platform.
+
 ## Installing via ghcup
 
-*Coming soon.* Installing `uplc-ghc` through
-[ghcup](https://www.haskell.org/ghcup/) — the standard installer for
-Haskell toolchains — is planned but not yet available. Until then, build
-from source as described below.
+`uplc-ghc` is distributed as a custom tool named `plinth` for
+[ghcup](https://www.haskell.org/ghcup/), the standard installer for Haskell
+toolchains. You need ghcup 0.2.1.0 or newer (check with `ghcup --version`).
+
+Add the Plinth release channel, then install and activate the tool:
+
+```console
+$ ghcup config add-release-channel https://raw.githubusercontent.com/input-output-hk/ghc-plinth/ghcup-channel/ghcup-plinth.yaml
+$ ghcup install plinth latest
+$ ghcup set plinth latest
+```
+
+`ghcup install` downloads the binary distribution for your platform and
+installs it under ghcup's own directory; `ghcup set` then symlinks `uplc-ghc`
+into ghcup's `bin` directory (`~/.ghcup/bin` by default), which is already on
+`PATH` for ghcup users. Verify with:
+
+```console
+$ uplc-ghc --version
+```
+
+Installing `plinth` does not affect any GHC installed by ghcup: the tool ships
+only the `uplc-*` binaries, so your regular `ghc` is left untouched.
+
+Binary distributions are published for:
+
+- Linux, x86_64 and aarch64 (glibc, and musl/Alpine)
+- macOS, Apple Silicon
+- Windows, x86_64
+
+List the available versions with `ghcup list -t plinth`. Once installed, head
+over to [Use uplc-ghc in a project]({% link how-to/use.md %}).
 
 ## Building from source
 

how-to/use.md

@@ -3,13 +3,21 @@ title: Use uplc-ghc in a project
 permalink: /how-to/use/
 ---
 
-The recommended way to use the Plinth standalone compiler is to set its path once in `cabal.project`.
+The recommended way to use the Plinth standalone compiler is to set it once in
+`cabal.project`. If you [installed it via ghcup]({% link how-to/build.md %})
+(the recommended way), `uplc-ghc` is on `PATH` and its name alone is enough:
 
 ```haskell
-with-compiler: /path/to/uplc-ghc
+with-compiler: uplc-ghc
 packages: .
 ```
 
+For a compiler built from source, give the path to the binary instead:
+
+```haskell
+with-compiler: /path/to/uplc-ghc
+```
+
 The same file also needs the Cardano package repository (CHaP), which provides
 the Cardano dependencies of the Plinth libraries:
 
@@ -41,15 +49,17 @@ are neither bundled with the compiler nor taken from CHaP. Pull them from the
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/ghc-plinth-plutus
-  tag: 33decd91baf18e76927ffd97a6c3d0ab571bbdb6
+  tag: 2e582ecde824238f927322d208740322eada8115
   subdir: plutus-tx
           plutus-core
           plutus-tx-plugin
 ```
 
 Use the `ghc-plinth-plutus` commit that matches your `uplc-ghc`: the compiler
 and these libraries are released together as a matched set, built from the same
-commit.
+commit. The commit above matches release 9.6.166.1 (the current ghcup
+`latest`); for a different `uplc-ghc`, use the plutus commit it was built
+from.
 
 In addition you may want to add the following `source-repository-package` blocks
 that build the C crypto libraries used by Cardano (`libsodium`, `secp256k1`,

tutorials/first-smart-contract.md

@@ -12,10 +12,12 @@ later.
 
 ## Before you start
 
-You need a built `uplc-ghc`. If you have not built it yet, follow
+You need `uplc-ghc` installed. If you do not have it yet, follow
 [Install Plinth standalone compiler]({% link how-to/build.md %}) first —
-this tutorial waits for you here. Note where the `uplc-ghc` binary ended up;
-throughout this tutorial, replace `/path/to/uplc-ghc` with its actual path.
+this tutorial waits for you here. If you installed it via ghcup (the
+recommended way), the binary is simply `uplc-ghc` on your `PATH`: wherever
+this tutorial says `/path/to/uplc-ghc`, write plain `uplc-ghc` instead. If
+you built from source, use the path of the binary the build produced.
 
 You will also need a recent `cabal` (3.8 or newer) on your `PATH`.
 
@@ -54,7 +56,7 @@ index-state:
 source-repository-package
   type: git
   location: https://github.com/input-output-hk/ghc-plinth-plutus
-  tag: 33decd91baf18e76927ffd97a6c3d0ab571bbdb6
+  tag: 2e582ecde824238f927322d208740322eada8115
   subdir: plutus-tx
           plutus-core
           plutus-tx-plugin
@@ -98,8 +100,9 @@ package sodium-clib
 
 Use the `ghc-plinth-plutus` commit that matches your `uplc-ghc`: the compiler and
 these libraries are released together as a matched set, built from the same
-commit. The commit above matches this guide's compiler; for a different
-`uplc-ghc`, use the plutus commit it was built from.
+commit. The commit above matches release 9.6.166.1 (the current ghcup
+`latest`); for a different `uplc-ghc`, use the plutus commit it was built
+from.
 
 **Not for production.** The vendored crypto C libraries pulled in by the
 `*-clib` `source-repository-package`s above have not been audited. Use this