diff --git a/581.myco b/581.myco
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--- a/581.myco
+++ /dev/null
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-= 581
-https://ethw.org/Ancient_Computers
-
diff --git a/648.myco b/648.myco
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--- /dev/null
+++ b/648.myco
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+= 648
+https://effectivetypescript.com/2023/09/27/closure-compiler/
+
+> This post looks at the Closure Compiler, Google's tool from the mid-2000s for adding types to JavaScript. It looks at how its focus on minification led to very different design choices than TypeScript, and how this and a few other factors led to TypeScript becoming the ubiquitous solution for JavaScript + types. The Closure Compiler represents an alternative path that JavaScript could have taken, and it gives us perspective on TypeScript as it exists today.
\ No newline at end of file
diff --git a/Ancient Computers.myco b/Ancient Computers.myco
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index afdc76b..0000000
--- a/Ancient Computers.myco	
+++ /dev/null
@@ -1,3 +0,0 @@
-= Ancient Computers
-https://ethw.org/Ancient_Computers
-
diff --git a/Effective TypeScript › The Saga of the Closure Compiler, and Why TypeScript Won.myco b/Effective TypeScript › The Saga of the Closure Compiler, and Why TypeScript Won.myco
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--- /dev/null
+++ b/Effective TypeScript › The Saga of the Closure Compiler, and Why TypeScript Won.myco	
@@ -0,0 +1,4 @@
+= Effective TypeScript › The Saga of the Closure Compiler, and Why TypeScript Won
+https://effectivetypescript.com/2023/09/27/closure-compiler/
+
+> This post looks at the Closure Compiler, Google's tool from the mid-2000s for adding types to JavaScript. It looks at how its focus on minification led to very different design choices than TypeScript, and how this and a few other factors led to TypeScript becoming the ubiquitous solution for JavaScript + types. The Closure Compiler represents an alternative path that JavaScript could have taken, and it gives us perspective on TypeScript as it exists today.
\ No newline at end of file