diff --git a/cf_list_create.js b/cf_list_create.js
index b57afea..e079709 100644
--- a/cf_list_create.js
+++ b/cf_list_create.js
@@ -10,6 +10,7 @@ import {
   FAST_MODE,
   LIST_ITEM_LIMIT,
   LIST_ITEM_SIZE,
+  PROCESSING_FILENAME,
 } from "./lib/constants.js";
 import { normalizeDomain } from "./lib/helpers.js";
 import {
@@ -19,12 +20,12 @@ import {
   readFile,
 } from "./lib/utils.js";
 
-const allowlistFilename = existsSync("whitelist.csv")
-  ? "whitelist.csv"
-  : "allowlist.txt";
-const blocklistFilename = existsSync("input.csv")
-  ? "input.csv"
-  : "blocklist.txt";
+const allowlistFilename = existsSync(PROCESSING_FILENAME.OLD_ALLOWLIST)
+  ? PROCESSING_FILENAME.OLD_ALLOWLIST
+  : PROCESSING_FILENAME.ALLOWLIST;
+const blocklistFilename = existsSync(PROCESSING_FILENAME.OLD_BLOCKLIST)
+  ? PROCESSING_FILENAME.OLD_BLOCKLIST
+  : PROCESSING_FILENAME.BLOCKLIST;
 const allowlist = new Map();
 const blocklist = new Map();
 const domains = [];
diff --git a/download_lists.js b/download_lists.js
index ee6c082..56e4a19 100644
--- a/download_lists.js
+++ b/download_lists.js
@@ -1,5 +1,6 @@
 import { resolve } from "path";
 
+import { LIST_TYPE, PROCESSING_FILENAME } from "./lib/constants.js";
 import { downloadFiles } from "./lib/utils.js";
 
 const allowlistUrls = [
@@ -40,25 +41,31 @@ const blocklistUrls = [
 const listType = process.argv[2];
 
 const downloadAllowlists = async () => {
-  await downloadFiles(resolve("./allowlist.txt"), allowlistUrls);
+  await downloadFiles(
+    resolve(`./${PROCESSING_FILENAME.ALLOWLIST}`),
+    allowlistUrls
+  );
   console.log(
-    "Done. The allowlist.txt file contains merged data from recommended whitelists."
+    `Done. The ${PROCESSING_FILENAME.ALLOWLIST} file contains merged data from recommended allowlists.`
   );
 };
 
 const downloadBlocklists = async () => {
-  await downloadFiles(resolve("./blocklist.txt"), blocklistUrls);
+  await downloadFiles(
+    resolve(`./${PROCESSING_FILENAME.BLOCKLIST}`),
+    blocklistUrls
+  );
   console.log(
-    "Done. The blocklist.txt file contains merged data from recommended filter lists."
+    `Done. The ${PROCESSING_FILENAME.BLOCKLIST} file contains merged data from recommended blocklists.`
   );
 };
 
 switch (listType) {
-  case "allowlist": {
+  case LIST_TYPE.ALLOWLIST: {
     await downloadAllowlists();
     break;
   }
-  case "blocklist": {
+  case LIST_TYPE.BLOCKLIST: {
     await downloadBlocklists();
     break;
   }
diff --git a/lib/constants.js b/lib/constants.js
index 5a77df5..9d5e124 100644
--- a/lib/constants.js
+++ b/lib/constants.js
@@ -19,3 +19,15 @@ export const API_HOST = "https://api.cloudflare.com/client/v4";
 export const DRY_RUN = !!parseInt(process.env.DRY_RUN, 10);
 
 export const FAST_MODE = !!parseInt(process.env.FAST_MODE, 10);
+
+export const PROCESSING_FILENAME = {
+  ALLOWLIST: "allowlist.txt",
+  BLOCKLIST: "blocklist.txt",
+  OLD_ALLOWLIST: "whitelist.csv",
+  OLD_BLOCKLIST: "input.csv",
+};
+
+export const LIST_TYPE = {
+  ALLOWLIST: "allowlist",
+  BLOCKLIST: "blocklist",
+};
diff --git a/lib/helpers.js b/lib/helpers.js
index 93e6ed0..702b4f3 100644
--- a/lib/helpers.js
+++ b/lib/helpers.js
@@ -1,9 +1,14 @@
 import { ACCOUNT_EMAIL, ACCOUNT_ID, API_HOST, API_TOKEN } from "./constants.js";
 
 if (!globalThis.fetch) {
-  console.warn("\nIMPORTANT: Your Node.js version doesn't have native fetch support and may not be supported in the future. Please update to v18 or later.\n")
+  console.warn(
+    "\nIMPORTANT: Your Node.js version doesn't have native fetch support and may not be supported in the future. Please update to v18 or later.\n"
+  );
   // Advise what to do if running in GitHub Actions
-  if (process.env.GITHUB_WORKSPACE) console.warn("Since you're running in GitHub Actions, you should update your Actions workflow configuration to use Node v18 or higher.") 
+  if (process.env.GITHUB_WORKSPACE)
+    console.warn(
+      "Since you're running in GitHub Actions, you should update your Actions workflow configuration to use Node v18 or higher."
+    );
   // Import node-fetch since there's no native fetch in this environment
   globalThis.fetch = (await import("node-fetch")).default;
 }
@@ -48,7 +53,7 @@ export const requestGateway = (path, options) =>
 /**
  * Normalizes a domain.
  * @param {string} value The value to be normalized.
- * @param {boolean} isAllowlisting Whether the value is to be whitelisted.
+ * @param {boolean} isAllowlisting Whether the value is to be allowlisted.
  * @returns {string}
  */
 export const normalizeDomain = (value, isAllowlisting) => {