diff --git a/CHANGELOG.rdoc b/CHANGELOG.rdoc
index b004220..5405b11 100644
--- a/CHANGELOG.rdoc
+++ b/CHANGELOG.rdoc
@@ -7,6 +7,8 @@ The file documents the changes to this library over the different versions.
 
 === Unreleased changes
 
+- Fixed functionality of #from_file within non-main Ractors.
+
 === 1.4.0 - 2020-12-28
 
 - Add compatibility for Ruby 3.0. 
diff --git a/lib/chunky_png.rb b/lib/chunky_png.rb
index b0c6675..654d1d1 100644
--- a/lib/chunky_png.rb
+++ b/lib/chunky_png.rb
@@ -143,7 +143,7 @@ class UnitsUnknown < ChunkyPNG::Exception
   # Null-byte, with the encoding set correctly to ASCII-8BIT (binary) in Ruby 1.9.
   # @return [String] A binary string, consisting of one NULL-byte.
   # @private
-  EXTRA_BYTE = "\0".b
+  EXTRA_BYTE = "\0".b.freeze
 end
 
 require "chunky_png/version"
diff --git a/lib/chunky_png/chunk.rb b/lib/chunky_png/chunk.rb
index 866f8ec..6bf10ad 100644
--- a/lib/chunky_png/chunk.rb
+++ b/lib/chunky_png/chunk.rb
@@ -467,6 +467,6 @@ def content
       "zTXt" => CompressedText,
       "iTXt" => InternationalText,
       "pHYs" => Physical,
-    }
+    }.freeze
   end
 end
diff --git a/lib/chunky_png/color.rb b/lib/chunky_png/color.rb
index a96b793..96a3304 100644
--- a/lib/chunky_png/color.rb
+++ b/lib/chunky_png/color.rb
@@ -888,7 +888,7 @@ def euclidean_distance_rgba(pixel_after, pixel_before)
       whitesmoke: 0xf5f5f500,
       yellow: 0xffff0000,
       yellowgreen: 0x9acd3200,
-    }
+    }.freeze
 
     # Gets a color value based on a HTML color name.
     #
diff --git a/spec/chunky_png/canvas_spec.rb b/spec/chunky_png/canvas_spec.rb
index 5e3c19c..c4bc1c9 100644
--- a/spec/chunky_png/canvas_spec.rb
+++ b/spec/chunky_png/canvas_spec.rb
@@ -237,4 +237,11 @@
       expect(subject.inspect).to eql "<ChunkyPNG::Canvas 1x1 [\n\t[#ffffffff]\n]>"
     end
   end
+  
+  it "should behave properly with the new Ruby 3.0 Ractors" do
+    filename = resource_file("operations.png")
+    ractor = Ractor.new { ChunkyPNG::Canvas.from_file(Ractor.receive) }
+    ractor.send(filename)
+    expect(ractor.take).to eql ChunkyPNG::Canvas.from_file(filename)
+  end
 end