在最新版本的自制程序（截至本文撰写时为0.9.5）上，将有一个你想要安装的自制桶版本的具体配方。例子：

$ brew search mongodb
mongodb    mongodb24  mongodb26

然后，像正常一样进行brew安装mongodb26。

如果您已经安装了最新版本，请确保取消链接最新版本并链接所需版本：brew unlink mongodb&&brew link mongob26。

解决方案

brew extract --version=8.4p1  openssh homebrew/cask
brew install openssh@8.4p1

最新的openssl@8.5p1在我运行brew升级后出现错误，因此我通过上述方式成功地备份到了以前的版本。

如果无法使用brew search<formula>找到您的版本，您也可以尝试查看公式的提交日志，以找到所需的版本：

下面是通过brew安装旧版本nginx的示例：

ngxnx公式提交日志参见nginx:更新1.6.3瓶装eba75b9a1a474b9fc4df30bd0a32637fa31ec049

从那里，我们可以使用sha和原始git url安装1.6.3：

brew安装https://raw.githubusercontent.com/Homebrew/homebrew/eba75b9a1a474b9fc4df30bd0a32637fa31ec049/Library/Formula/nginx.rb

基于@tschundee和@Debilski的更新1所描述的工作流，我自动化了该过程，并在此脚本中添加了清理。

下载它，将其放到您的路径中，然后brewv<formula_name><wanted_version>。对于特定OP，它将是：

cd path/to/downloaded/script/
./brewv postgresql 8.4.4

:)

UPDATE：此方法已弃用，不再有效。

此方法导致错误：不支持从GitHub提交URL安装mysql！brew将mysql提取到GitHub上的稳定水龙头。（用法错误）

$ brew install https://raw.githubusercontent.com/Homebrew/homebrew-core/c77882756a832ac1d87e7396c114158e5619016c/Formula/mysql.rb
Updating Homebrew...
==> Auto-updated Homebrew!
Updated 2 taps (homebrew/core and homebrew/cask).

...

Traceback (most recent call last):
    9: from /usr/local/Homebrew/Library/Homebrew/brew.rb:122:in `<main>'
    8: from /usr/local/Homebrew/Library/Homebrew/cmd/install.rb:132:in `install'
    7: from /usr/local/Homebrew/Library/Homebrew/cli/parser.rb:302:in `parse'
    6: from /usr/local/Homebrew/Library/Homebrew/cli/parser.rb:651:in `formulae'
    5: from /usr/local/Homebrew/Library/Homebrew/cli/parser.rb:651:in `map'
    4: from /usr/local/Homebrew/Library/Homebrew/cli/parser.rb:655:in `block in formulae'
    3: from /usr/local/Homebrew/Library/Homebrew/formulary.rb:351:in `factory'
    2: from /usr/local/Homebrew/Library/Homebrew/formulary.rb:138:in `get_formula'
    1: from /usr/local/Homebrew/Library/Homebrew/formulary.rb:142:in `klass'
/usr/local/Homebrew/Library/Homebrew/formulary.rb:227:in `load_file': Invalid usage: Installation of mysql from a GitHub commit URL is unsupported! `brew extract mysql` to a stable tap on GitHub instead. (UsageError)
    12: from /usr/local/Homebrew/Library/Homebrew/brew.rb:155:in `<main>'
    11: from /usr/local/Homebrew/Library/Homebrew/brew.rb:157:in `rescue in <main>'
    10: from /usr/local/Homebrew/Library/Homebrew/help.rb:64:in `help'
     9: from /usr/local/Homebrew/Library/Homebrew/help.rb:83:in `command_help'
     8: from /usr/local/Homebrew/Library/Homebrew/help.rb:103:in `parser_help'
     7: from /usr/local/Homebrew/Library/Homebrew/cli/parser.rb:302:in `parse'
     6: from /usr/local/Homebrew/Library/Homebrew/cli/parser.rb:651:in `formulae'
     5: from /usr/local/Homebrew/Library/Homebrew/cli/parser.rb:651:in `map'
     4: from /usr/local/Homebrew/Library/Homebrew/cli/parser.rb:655:in `block in formulae'
     3: from /usr/local/Homebrew/Library/Homebrew/formulary.rb:351:in `factory'
     2: from /usr/local/Homebrew/Library/Homebrew/formulary.rb:138:in `get_formula'
     1: from /usr/local/Homebrew/Library/Homebrew/formulary.rb:142:in `klass'
/usr/local/Homebrew/Library/Homebrew/formulary.rb:227:in `load_file': Invalid usage: Installation of mysql from a GitHub commit URL is unsupported! `brew extract mysql` to a stable tap on GitHub instead. (UsageError)

我尝试使用推荐的命令进行安装，但它在MySQL 5.7.10的这个特定实例中不起作用。你可能会有更好的运气与更新的公式。

$ brew extract --version=5.7.10 mysql homebrew/cask
==> Searching repository history
==> Writing formula for mysql from revision 0fa511b to:
/usr/local/Homebrew/Library/Taps/homebrew/homebrew-cask/Formula/mysql@5.7.10.rb

$ 

$ brew install /usr/local/Homebrew/Library/Taps/homebrew/homebrew-cask/Formula/mysql@5.7.10.rb
Updating Homebrew...
==> Auto-updated Homebrew!
Updated 1 tap (homebrew/core).
==> Updated Formulae
Updated 1 formula.
Error: undefined method `core_tap?' for nil:NilClass

Error: Failed to load cask: /usr/local/Homebrew/Library/Taps/homebrew/homebrew-cask/Formula/mysql@5.7.10.rb
Cask 'mysql@5.7.10' is unreadable: wrong constant name #<Class:0x00007f9b9498cad8>
Warning: Treating /usr/local/Homebrew/Library/Taps/homebrew/homebrew-cask/Formula/mysql@5.7.10.rb as a formula.
==> Installing mysql@5.7.10 from homebrew/cask
==> Downloading https://homebrew.bintray.com/bottles/cmake-3.19.4.big_sur.bottle.tar.gz
==> Downloading from https://d29vzk4ow07wi7.cloudfront.net/278f2ad1caf664019ff7b4a7fc5493999c06adf503637447af13a617d45cf484?response-content-disposition=attachment%3Bfilenam
######################################################################## 100.0%
==> Downloading https://downloads.sourceforge.net/project/boost/boost/1.59.0/boost_1_59_0.tar.bz2
==> Downloading from https://phoenixnap.dl.sourceforge.net/project/boost/boost/1.59.0/boost_1_59_0.tar.bz2
######################################################################## 100.0%
==> Downloading https://cdn.mysql.com/Downloads/MySQL-5.7/mysql-5.7.10.tar.gz

curl: (22) The requested URL returned error: 404 Not Found
Error: Failed to download resource "mysql@5.7.10"
Download failed: https://cdn.mysql.com/Downloads/MySQL-5.7/mysql-5.7.10.tar.gz

您可以在上面的路径中修改公式（用ruby编写），以尝试实现所需的结果（例如，在最近的macOS版本上安装MySQL 5.7.10）。

您可以使用识别公式和公式历史记录中与您要安装的软件包版本匹配的特定提交的策略。

去https://github.com/Homebrew/homebrew-core按键盘上的t启动文件查找器。确定一个看起来最相关的公式，可能是：formula/mysql.rb，将您带到forumla文件位置：https://github.com/Homebrew/homebrew-core/blob/master/Formula/mysql.rb.单击历史记录按钮查看修订历史记录，该按钮位于https://github.com/Homebrew/homebrew-core/commits/master/Formula/mysql.rb.如果您对MySQL 5.7.10感兴趣，可以单击5.7.11之前的最新版本，该版本导航到GitHub提交：

https://github.com/Homebrew/homebrew-core/commit/c77882756a832ac1d87e7396c114158e5619016c#Formula/mysql.rb

注意：如果提交历史没有加载到浏览器中，您可能需要根据GitHub的建议在控制台中查看提交历史。如果您有兴趣在GitHub上看到提交，请在URL中替换上面的提交SHA。或者，跳到下面的步骤7。

应用提交后，单击“查看”按钮查看mysql.rb文件的源代码。然后单击“原始”按钮查看原始源。复制URL。或者，使用mysql.rb文件名自己构建URL，以标识您的公式和该公式的特定版本（由以下URL中的commmit SHA标识）。

https://raw.githubusercontent.com/Homebrew/homebrew-core/c77882756a832ac1d87e7396c114158e5619016c/Formula/mysql.rb

使用$brew Install[步骤7的URL]安装它$brew安装https://raw.githubusercontent.com/Homebrew/homebrew-core/c77882756a832ac1d87e7396c114158e5619016c/Formula/mysql.rb

这里的其他答案很好，但如果您需要安装较旧版本的软件包并确保修改了软件包名称，则需要另一种方法。当使用脚本（在我的例子中是PHP构建脚本）时，这一点非常重要，这些脚本使用brew前缀package_name来确定要用于编译的目录。

如果您正在使用brew提取，则会在包名称的末尾添加一个版本，这将中断brew前缀查找。

以下是如何在保持原始软件包名称的同时安装较旧的软件包版本：

# uninstall the newer version of the package that you accidentally installed
brew uninstall --ignore-dependencies icu4c

# `extract` the version you'd like to install into a custom tap
brew tap-new $USER/local-tap
brew extract --version=68.2 icu4c $USER/local-tap

# jump into the new tap you created
cd $(brew --repository $USER/local-tap)/Formula

# rename the formula
mv icu4c@68.2.rb icu4c.rb

# change the name of the formula by removing "AT682" from the `class` definition
# the exact text you'll need to remove will be different
# depending on the version you extracted
nano icu4c.rb

# then, install this specific formula directly
brew install $(brew --repository $USER/local-tap)/Formula/icu4c.rb

我在这里写了更多。