diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index ed3c51fd..d707f33c 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -8,7 +8,7 @@ jobs:
       fail-fast: false
       matrix:
         ruby:
-        - '2.7'
+        - '2.7.0'
         - '3.0'
         - '3.1'
         - head
diff --git a/Rakefile b/Rakefile
index 6ba17fe9..4973d45e 100644
--- a/Rakefile
+++ b/Rakefile
@@ -12,8 +12,17 @@ end
 
 task default: :test
 
-SOURCE_FILES =
-  FileList[%w[Gemfile Rakefile syntax_tree.gemspec lib/**/*.rb test/*.rb]]
+configure = ->(task) do
+  task.source_files =
+    FileList[%w[Gemfile Rakefile syntax_tree.gemspec lib/**/*.rb test/*.rb]]
 
-SyntaxTree::Rake::CheckTask.new { |t| t.source_files = SOURCE_FILES }
-SyntaxTree::Rake::WriteTask.new { |t| t.source_files = SOURCE_FILES }
+  # Since Syntax Tree supports back to Ruby 2.7.0, we need to make sure that we
+  # format our code such that it's compatible with that version. This actually
+  # has very little effect on the output, the only change at the moment is that
+  # Ruby < 2.7.3 didn't allow a newline before the closing brace of a hash
+  # pattern.
+  task.target_ruby_version = Gem::Version.new("2.7.0")
+end
+
+SyntaxTree::Rake::CheckTask.new(&configure)
+SyntaxTree::Rake::WriteTask.new(&configure)
diff --git a/lib/syntax_tree/cli.rb b/lib/syntax_tree/cli.rb
index 65c71f4d..2de20e78 100644
--- a/lib/syntax_tree/cli.rb
+++ b/lib/syntax_tree/cli.rb
@@ -53,10 +53,13 @@ def source
       end
     end
 
-    # An item of work that corresponds to a script content passed via the command line.
+    # An item of work that corresponds to a script content passed via the
+    # command line.
     class ScriptItem
       FILEPATH = :script
 
+      attr_reader :source
+
       def initialize(source)
         @source = source
       end
@@ -68,10 +71,6 @@ def handler
       def filepath
         FILEPATH
       end
-
-      def source
-        @source
-      end
     end
 
     # The parent action class for the CLI that implements the basics.
@@ -197,7 +196,7 @@ def run(item)
 
         source = item.source
         formatted = item.handler.format(source, options.print_width)
-        File.write(filepath, formatted) if FileItem === item
+        File.write(filepath, formatted) if item.filepath != :script
 
         color = source == formatted ? Color.gray(filepath) : filepath
         delta = ((Time.now - start) * 1000).round
@@ -259,13 +258,19 @@ def run(item)
     # responsible for parsing the list and then returning the file paths at the
     # end.
     class Options
-      attr_reader :print_width, :scripts
+      attr_reader :plugins, :print_width, :scripts, :target_ruby_version
 
       def initialize(print_width: DEFAULT_PRINT_WIDTH)
+        @plugins = []
         @print_width = print_width
         @scripts = []
+        @target_ruby_version = nil
       end
 
+      # TODO: This function causes a couple of side-effects that I really don't
+      # like to have here. It mutates the global state by requiring the plugins,
+      # and mutates the global options hash by adding the target ruby version.
+      # That should be done on a config-by-config basis, not here.
       def parse(arguments)
         parser.parse!(arguments)
       end
@@ -285,7 +290,8 @@ def parser
           #     require "syntax_tree/haml"
           #
           opts.on("--plugins=PLUGINS") do |plugins|
-            plugins.split(",").each { |plugin| require "syntax_tree/#{plugin}" }
+            @plugins = plugins.split(",")
+            @plugins.each { |plugin| require "syntax_tree/#{plugin}" }
           end
 
           # If there is a print width specified on the command line, then
@@ -296,8 +302,13 @@ def parser
 
           # If there is a script specified on the command line, then parse
           # it and add it to the list of scripts to run.
-          opts.on("-e SCRIPT") do |script|
-            @scripts << script
+          opts.on("-e SCRIPT") { |script| @scripts << script }
+
+          # If there is a target ruby version specified on the command line,
+          # parse that out and use it when formatting.
+          opts.on("--target-ruby-version=VERSION") do |version|
+            @target_ruby_version = Gem::Version.new(version)
+            Formatter::OPTIONS[:target_ruby_version] = @target_ruby_version
           end
         end
       end
@@ -395,9 +406,7 @@ def run(argv)
                 queue << FileItem.new(filepath) if File.file?(filepath)
               end
           end
-          options.scripts.each do |script|
-            queue << ScriptItem.new(script)
-          end
+          options.scripts.each { |script| queue << ScriptItem.new(script) }
         else
           queue << ScriptItem.new($stdin.read)
         end
diff --git a/lib/syntax_tree/formatter.rb b/lib/syntax_tree/formatter.rb
index c52e45ad..4c7a00db 100644
--- a/lib/syntax_tree/formatter.rb
+++ b/lib/syntax_tree/formatter.rb
@@ -14,7 +14,11 @@ class Formatter < PrettierPrint
     # Note that we're keeping this in a global-ish hash instead of just
     # overriding methods on classes so that other plugins can reference this if
     # necessary. For example, the RBS plugin references the quote style.
-    OPTIONS = { quote: "\"", trailing_comma: false }
+    OPTIONS = {
+      quote: "\"",
+      trailing_comma: false,
+      target_ruby_version: Gem::Version.new(RUBY_VERSION)
+    }
 
     COMMENT_PRIORITY = 1
     HEREDOC_PRIORITY = 2
@@ -23,14 +27,15 @@ class Formatter < PrettierPrint
 
     # These options are overridden in plugins to we need to make sure they are
     # available here.
-    attr_reader :quote, :trailing_comma
+    attr_reader :quote, :trailing_comma, :target_ruby_version
     alias trailing_comma? trailing_comma
 
     def initialize(
       source,
       *args,
       quote: OPTIONS[:quote],
-      trailing_comma: OPTIONS[:trailing_comma]
+      trailing_comma: OPTIONS[:trailing_comma],
+      target_ruby_version: OPTIONS[:target_ruby_version]
     )
       super(*args)
 
@@ -40,6 +45,7 @@ def initialize(
       # Memoizing these values per formatter to make access faster.
       @quote = quote
       @trailing_comma = trailing_comma
+      @target_ruby_version = target_ruby_version
     end
 
     def self.format(source, node)
diff --git a/lib/syntax_tree/node.rb b/lib/syntax_tree/node.rb
index d7b6d6cf..47c534d1 100644
--- a/lib/syntax_tree/node.rb
+++ b/lib/syntax_tree/node.rb
@@ -2132,8 +2132,7 @@ def format(q)
         in [
              Paren[
                contents: {
-                 body: [ArrayLiteral[contents: { parts: [_, _, *] }] => array]
-               }
+                 body: [ArrayLiteral[contents: { parts: [_, _, *] }] => array] }
              ]
            ]
           # Here we have a single argument that is a set of parentheses wrapping
@@ -5116,8 +5115,13 @@ def format(q)
           q.breakable
           contents.call
         end
-        q.breakable
-        q.text("}")
+
+        if q.target_ruby_version < Gem::Version.new("2.7.3")
+          q.text(" }")
+        else
+          q.breakable
+          q.text("}")
+        end
       end
     end
   end
@@ -5204,8 +5208,7 @@ def call(q, node)
             false
           in {
                statements: { body: [truthy] },
-               consequent: Else[statements: { body: [falsy] }]
-             }
+               consequent: Else[statements: { body: [falsy] }] }
             ternaryable?(truthy) && ternaryable?(falsy)
           else
             false
diff --git a/lib/syntax_tree/rake/check_task.rb b/lib/syntax_tree/rake/check_task.rb
index afe5013c..48247718 100644
--- a/lib/syntax_tree/rake/check_task.rb
+++ b/lib/syntax_tree/rake/check_task.rb
@@ -39,16 +39,22 @@ class CheckTask < ::Rake::TaskLib
       # Defaults to 80.
       attr_accessor :print_width
 
+      # The target Ruby version to use for formatting.
+      # Defaults to Gem::Version.new(RUBY_VERSION).
+      attr_accessor :target_ruby_version
+
       def initialize(
         name = :"stree:check",
         source_files = ::Rake::FileList["lib/**/*.rb"],
         plugins = [],
-        print_width = DEFAULT_PRINT_WIDTH
+        print_width = DEFAULT_PRINT_WIDTH,
+        target_ruby_version = Gem::Version.new(RUBY_VERSION)
       )
         @name = name
         @source_files = source_files
         @plugins = plugins
         @print_width = print_width
+        @target_ruby_version = target_ruby_version
 
         yield self if block_given?
         define_task
@@ -64,10 +70,15 @@ def define_task
       def run_task
         arguments = ["check"]
         arguments << "--plugins=#{plugins.join(",")}" if plugins.any?
+
         if print_width != DEFAULT_PRINT_WIDTH
           arguments << "--print-width=#{print_width}"
         end
 
+        if target_ruby_version != Gem::Version.new(RUBY_VERSION)
+          arguments << "--target-ruby-version=#{target_ruby_version}"
+        end
+
         SyntaxTree::CLI.run(arguments + Array(source_files))
       end
     end
diff --git a/lib/syntax_tree/rake/write_task.rb b/lib/syntax_tree/rake/write_task.rb
index 9a9e8330..69ce97e7 100644
--- a/lib/syntax_tree/rake/write_task.rb
+++ b/lib/syntax_tree/rake/write_task.rb
@@ -39,16 +39,22 @@ class WriteTask < ::Rake::TaskLib
       # Defaults to 80.
       attr_accessor :print_width
 
+      # The target Ruby version to use for formatting.
+      # Defaults to Gem::Version.new(RUBY_VERSION).
+      attr_accessor :target_ruby_version
+
       def initialize(
         name = :"stree:write",
         source_files = ::Rake::FileList["lib/**/*.rb"],
         plugins = [],
-        print_width = DEFAULT_PRINT_WIDTH
+        print_width = DEFAULT_PRINT_WIDTH,
+        target_ruby_version = Gem::Version.new(RUBY_VERSION)
       )
         @name = name
         @source_files = source_files
         @plugins = plugins
         @print_width = print_width
+        @target_ruby_version = target_ruby_version
 
         yield self if block_given?
         define_task
@@ -64,10 +70,15 @@ def define_task
       def run_task
         arguments = ["write"]
         arguments << "--plugins=#{plugins.join(",")}" if plugins.any?
+
         if print_width != DEFAULT_PRINT_WIDTH
           arguments << "--print-width=#{print_width}"
         end
 
+        if target_ruby_version != Gem::Version.new(RUBY_VERSION)
+          arguments << "--target-ruby-version=#{target_ruby_version}"
+        end
+
         SyntaxTree::CLI.run(arguments + Array(source_files))
       end
     end
diff --git a/syntax_tree.gemspec b/syntax_tree.gemspec
index 820a61a0..2b461dfd 100644
--- a/syntax_tree.gemspec
+++ b/syntax_tree.gemspec
@@ -19,7 +19,7 @@ Gem::Specification.new do |spec|
         .reject { |f| f.match(%r{^(test|spec|features)/}) }
     end
 
-  spec.required_ruby_version = ">= 2.7.3"
+  spec.required_ruby_version = ">= 2.7.0"
 
   spec.bindir = "exe"
   spec.executables = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
diff --git a/test/cli_test.rb b/test/cli_test.rb
index 4e8959e2..aec8f820 100644
--- a/test/cli_test.rb
+++ b/test/cli_test.rb
@@ -134,12 +134,12 @@ def test_no_arguments_no_tty
     end
 
     def test_inline_script
-      stdio, = capture_io { SyntaxTree::CLI.run(["format", "-e", "1+1"]) }
+      stdio, = capture_io { SyntaxTree::CLI.run(%w[format -e 1+1]) }
       assert_equal("1 + 1\n", stdio)
     end
 
     def test_multiple_inline_scripts
-      stdio, = capture_io { SyntaxTree::CLI.run(["format", "-e", "1+1", "-e", "2+2"]) }
+      stdio, = capture_io { SyntaxTree::CLI.run(%w[format -e 1+1 -e 2+2]) }
       assert_equal("1 + 1\n2 + 2\n", stdio)
     end
 
diff --git a/test/fixtures/args_forward.rb b/test/fixtures/args_forward.rb
index 5ba618a8..cc538f44 100644
--- a/test/fixtures/args_forward.rb
+++ b/test/fixtures/args_forward.rb
@@ -1,4 +1,4 @@
-%
+% # >= 2.7.3
 def foo(...)
   bar(:baz, ...)
 end
diff --git a/test/fixtures/hshptn.rb b/test/fixtures/hshptn.rb
index 505336b8..02d1cf75 100644
--- a/test/fixtures/hshptn.rb
+++ b/test/fixtures/hshptn.rb
@@ -30,7 +30,7 @@
 case foo
 in **bar
 end
-%
+% # >= 2.7.3
 case foo
 in {
      foo:, # comment1
diff --git a/test/fixtures/params.rb b/test/fixtures/params.rb
index 67b6ec90..551aa9a5 100644
--- a/test/fixtures/params.rb
+++ b/test/fixtures/params.rb
@@ -16,7 +16,7 @@ def foo(*)
 %
 def foo(*rest)
 end
-%
+% # >= 2.7.3
 def foo(...)
 end
 %
diff --git a/test/node_test.rb b/test/node_test.rb
index 30776f9d..07c2fe26 100644
--- a/test/node_test.rb
+++ b/test/node_test.rb
@@ -104,16 +104,18 @@ def test_arg_star
       end
     end
 
-    def test_args_forward
-      source = <<~SOURCE
-        def get(...)
-          request(:GET, ...)
-        end
-      SOURCE
+    guard_version("2.7.3") do
+      def test_args_forward
+        source = <<~SOURCE
+          def get(...)
+            request(:GET, ...)
+          end
+        SOURCE
 
-      at = location(lines: 2..2, chars: 29..32)
-      assert_node(ArgsForward, source, at: at) do |node|
-        node.bodystmt.statements.body.first.arguments.arguments.parts.last
+        at = location(lines: 2..2, chars: 29..32)
+        assert_node(ArgsForward, source, at: at) do |node|
+          node.bodystmt.statements.body.first.arguments.arguments.parts.last
+        end
       end
     end
 
diff --git a/test/test_helper.rb b/test/test_helper.rb
index 895fbc82..80e514f0 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -26,7 +26,7 @@ def initialize
         @called = nil
       end
 
-      def method_missing(called, ...)
+      def method_missing(called, *, **)
         @called = called
       end
     end