diff --git a/dist/index.js b/dist/index.js
index 62746316..e8ef8e58 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -148557,17 +148557,6 @@ async function installUnixSystemPackages() {
         }
     }
 }
-async function updateUnixPackageIndexFiles() {
-    const isGitHubRunner = external_node_process_.env.GITHUB_ACTIONS === "true";
-    if (isGitHubRunner) {
-        if (PLATFORM === "linux") {
-            await (0,lib_exec.exec)("sudo", ["apt-get", "update"]);
-        }
-        else if (PLATFORM === "macos") {
-            await (0,lib_exec.exec)("brew", ["update"]);
-        }
-    }
-}
 
 ;// CONCATENATED MODULE: ./src/opam.ts
 
@@ -148632,17 +148621,9 @@ async function acquireOpam() {
 }
 async function initializeOpam() {
     await lib_core.group("Initialise opam state", async () => {
+        await (0,lib_exec.exec)("opam", ["update", "--depexts"]);
         if (PLATFORM !== "windows") {
-            try {
-                await installUnixSystemPackages();
-            }
-            catch (error) {
-                if (error instanceof Error) {
-                    lib_core.notice(`An error has been caught in some system package index files, so the system package index files have been re-synchronised, and the system package installation has been retried: ${error.message.toLocaleLowerCase()}`);
-                }
-                await updateUnixPackageIndexFiles();
-                await installUnixSystemPackages();
-            }
+            await installUnixSystemPackages();
         }
         const extraOptions = [];
         if (PLATFORM === "windows") {
diff --git a/packages/setup-ocaml/src/opam.ts b/packages/setup-ocaml/src/opam.ts
index 1a215271..a3c00199 100644
--- a/packages/setup-ocaml/src/opam.ts
+++ b/packages/setup-ocaml/src/opam.ts
@@ -13,10 +13,7 @@ import {
   OPAM_DISABLE_SANDBOXING,
   PLATFORM,
 } from "./constants.js";
-import {
-  installUnixSystemPackages,
-  updateUnixPackageIndexFiles,
-} from "./unix.js";
+import { installUnixSystemPackages } from "./unix.js";
 
 export async function retrieveLatestOpamRelease() {
   const semverRange = ALLOW_PRERELEASE_OPAM ? "*" : "<2.4.0";
@@ -88,18 +85,9 @@ async function acquireOpam() {
 
 async function initializeOpam() {
   await core.group("Initialise opam state", async () => {
+    await exec("opam", ["update", "--depexts"]);
     if (PLATFORM !== "windows") {
-      try {
-        await installUnixSystemPackages();
-      } catch (error) {
-        if (error instanceof Error) {
-          core.notice(
-            `An error has been caught in some system package index files, so the system package index files have been re-synchronised, and the system package installation has been retried: ${error.message.toLocaleLowerCase()}`,
-          );
-        }
-        await updateUnixPackageIndexFiles();
-        await installUnixSystemPackages();
-      }
+      await installUnixSystemPackages();
     }
     const extraOptions = [];
     if (PLATFORM === "windows") {
diff --git a/packages/setup-ocaml/src/unix.ts b/packages/setup-ocaml/src/unix.ts
index abb58704..74162925 100644
--- a/packages/setup-ocaml/src/unix.ts
+++ b/packages/setup-ocaml/src/unix.ts
@@ -56,14 +56,3 @@ export async function installUnixSystemPackages() {
     }
   }
 }
-
-export async function updateUnixPackageIndexFiles() {
-  const isGitHubRunner = process.env.GITHUB_ACTIONS === "true";
-  if (isGitHubRunner) {
-    if (PLATFORM === "linux") {
-      await exec("sudo", ["apt-get", "update"]);
-    } else if (PLATFORM === "macos") {
-      await exec("brew", ["update"]);
-    }
-  }
-}