diff --git a/config/codemod-const.js b/config/codemod-const.js
deleted file mode 100644
index 37eee5b769..0000000000
--- a/config/codemod-const.js
+++ /dev/null
@@ -1,43 +0,0 @@
-/* eslint no-console:0 */
-
-/** Find constants (identified by ALL_CAPS_DECLARATIONS), and inline them globally.
- *	This is safe because Preact *only* uses global constants.
- */
-export default (file, api) => {
-	let j = api.jscodeshift,
-		code = j(file.source),
-		constants = {},
-		found = 0;
-
-	code
-		.find(j.VariableDeclaration)
-		.filter(decl => {
-			for (let i = decl.value.declarations.length; i--; ) {
-				let node = decl.value.declarations[i],
-					name = node.id && node.id.name,
-					init = node.init;
-				if (name && init && name.match(/^[A-Z0-9_$]+$/g) && !init.regex) {
-					if (init.type === 'Literal') {
-						// console.log(`Inlining constant: ${name}=${init.raw}`);
-						found++;
-						constants[name] = init;
-						// remove declaration
-						decl.value.declarations.splice(i, 1);
-						// if it's the last, we'll remove the whole statement
-						return !decl.value.declarations.length;
-					}
-				}
-			}
-			return false;
-		})
-		.remove();
-
-	code
-		.find(j.Identifier)
-		.filter(
-			path => path.value.name && constants.hasOwnProperty(path.value.name)
-		)
-		.replaceWith(path => (found++, constants[path.value.name]));
-
-	return found ? code.toSource({ quote: 'single' }) : null;
-};
diff --git a/config/codemod-let-name.js b/config/codemod-let-name.js
deleted file mode 100644
index 5f69411ed4..0000000000
--- a/config/codemod-let-name.js
+++ /dev/null
@@ -1,16 +0,0 @@
-/**
- * Restores var names transformed by babel's let block scoping
- */
-export default (file, api) => {
-	let j = api.jscodeshift;
-	let code = j(file.source);
-
-	// @TODO unsafe, but without it we gain 20b gzipped: https://www.diffchecker.com/bVrOJWTO
-	code
-		.findVariableDeclarators()
-		.filter(d => /^_i/.test(d.value.id.name))
-		.renameTo('i');
-	code.findVariableDeclarators('_key').renameTo('key');
-
-	return code.toSource({ quote: 'single' });
-};
diff --git a/config/codemod-strip-tdz.js b/config/codemod-strip-tdz.js
deleted file mode 100644
index 469c9c32a5..0000000000
--- a/config/codemod-strip-tdz.js
+++ /dev/null
@@ -1,60 +0,0 @@
-/* eslint no-console:0 */
-
-// parent node types that we don't want to remove pointless initializations from (because it breaks hoisting)
-const BLOCKED = ['ForStatement', 'WhileStatement']; // 'IfStatement', 'SwitchStatement'
-
-/** Removes var initialization to `void 0`, which Babel adds for TDZ strictness. */
-export default (file, api) => {
-	let { jscodeshift } = api,
-		found = 0;
-
-	let code = jscodeshift(file.source)
-		.find(jscodeshift.VariableDeclaration)
-		.forEach(handleDeclaration);
-
-	function handleDeclaration(decl) {
-		let p = decl,
-			remove = true;
-
-		while ((p = p.parentPath)) {
-			if (~BLOCKED.indexOf(p.value.type)) {
-				remove = false;
-				break;
-			}
-		}
-
-		decl.value.declarations.filter(isPointless).forEach(node => {
-			if (remove === false) {
-				console.log(
-					`> Skipping removal of undefined init for "${node.id.name}": within ${p.value.type}`
-				);
-			} else {
-				removeNodeInitialization(node);
-			}
-		});
-	}
-
-	function removeNodeInitialization(node) {
-		node.init = null;
-		found++;
-	}
-
-	function isPointless(node) {
-		let { init } = node;
-		if (init) {
-			if (
-				init.type === 'UnaryExpression' &&
-				init.operator === 'void' &&
-				init.argument.value == 0
-			) {
-				return true;
-			}
-			if (init.type === 'Identifier' && init.name === 'undefined') {
-				return true;
-			}
-		}
-		return false;
-	}
-
-	return found ? code.toSource({ quote: 'single' }) : null;
-};