diff --git a/lib/dotenvious/env_appender.rb b/lib/dotenvious/env_appender.rb
index 5e9554c..fffc147 100644
--- a/lib/dotenvious/env_appender.rb
+++ b/lib/dotenvious/env_appender.rb
@@ -6,6 +6,7 @@ def initialize(filename)
 
     def append(key)
       env.write("#{key}=#{ENV_EXAMPLE[key]}\n")
+      env.close
     end
 
     private
diff --git a/lib/dotenvious/value_replacer.rb b/lib/dotenvious/value_replacer.rb
index 95022ce..699bb56 100644
--- a/lib/dotenvious/value_replacer.rb
+++ b/lib/dotenvious/value_replacer.rb
@@ -11,6 +11,7 @@ def replace(key)
       updated_env = base_env.dup
       updated_env[line_number] = "#{key}=#{ENV_EXAMPLE[key]}"
       env_writer.write(updated_env.join("\n") + "\n")
+      env_writer.close
     end
 
     private
@@ -22,7 +23,7 @@ def base_env
     end
 
     def env_writer
-      File.open(filename, 'w')
+      @env_writer ||= File.open(filename, 'w')
     end
   end
 end
diff --git a/spec/dotenvious/env_appender_spec.rb b/spec/dotenvious/env_appender_spec.rb
index 040f3ea..113fe56 100644
--- a/spec/dotenvious/env_appender_spec.rb
+++ b/spec/dotenvious/env_appender_spec.rb
@@ -9,6 +9,7 @@
     it 'appends the value to the end of the .env file' do
       env_double = double('File', write: nil)
       expect(env_double).to receive(:write).with("test2=example2\n")
+      expect(env_double).to receive(:close)
       expect(File).to receive(:open).
         with('.big-ol-env', 'a+').once.
         and_return(env_double)
diff --git a/spec/dotenvious/prompter_spec.rb b/spec/dotenvious/prompter_spec.rb
index 3028b37..bff90ba 100644
--- a/spec/dotenvious/prompter_spec.rb
+++ b/spec/dotenvious/prompter_spec.rb
@@ -16,9 +16,13 @@
 
     it 'appends the vars to .env' do
       expect(STDIN).to receive(:gets).twice.and_return('y','n')
+      file_double = double
+      expect(file_double).to receive(:write).with("test2=\n")
+      expect(file_double).to receive(:close)
+
       expect(File).to receive(:open).
         with('.env', 'a+').once.
-        and_return(double('File', write: nil))
+        and_return(file_double)
 
       described_class.new.run
     end
@@ -28,5 +32,8 @@
 
       described_class.new.run
     end
+
+    xit 'given missing and different args, appends/rewrites correctly into env' do
+    end
   end
 end
diff --git a/spec/dotenvious/value_replacer_spec.rb b/spec/dotenvious/value_replacer_spec.rb
index 8b47f96..8f31cce 100644
--- a/spec/dotenvious/value_replacer_spec.rb
+++ b/spec/dotenvious/value_replacer_spec.rb
@@ -14,6 +14,7 @@
 
         env_double = double('File', write: nil)
         expect(env_double).to receive(:write).with("test=1234\nfake=correct\n")
+        expect(env_double).to receive(:close)
 
         expect(File).to receive(:open).
           with('.big-ol-env', 'w').