5 files changed, 30 insertions, 0 deletions
diff --git a/cli/tests/unit/os_test.ts b/cli/tests/unit/os_test.ts
index 5e88f02c1..ae2bee72e 100644
--- a/cli/tests/unit/os_test.ts
+++ b/cli/tests/unit/os_test.ts
@@ -239,6 +239,18 @@ Deno.test({ permissions: { sys: false } }, function releasePerm() {
   }, Deno.errors.PermissionDenied);
 });
 
+Deno.test({ permissions: { sys: ["osUptime"] } }, function osUptime() {
+  const uptime = Deno.osUptime();
+  assert(typeof uptime === "number");
+  assert(uptime > 0);
+});
+
+Deno.test({ permissions: { sys: false } }, function osUptimePerm() {
+  assertThrows(() => {
+    Deno.osUptime();
+  }, Deno.errors.PermissionDenied);
+});
+
 Deno.test(
   { permissions: { sys: ["systemMemoryInfo"] } },
   function systemMemoryInfo() {
diff --git a/cli/tests/unit/permissions_test.ts b/cli/tests/unit/permissions_test.ts
index 3387913e8..3af2e35ea 100644
--- a/cli/tests/unit/permissions_test.ts
+++ b/cli/tests/unit/permissions_test.ts
@@ -22,6 +22,7 @@ Deno.test(async function permissionNetInvalidHost() {
 Deno.test(async function permissionSysValidKind() {
   await Deno.permissions.query({ name: "sys", kind: "loadavg" });
   await Deno.permissions.query({ name: "sys", kind: "osRelease" });
+  await Deno.permissions.query({ name: "sys", kind: "osUptime" });
   await Deno.permissions.query({ name: "sys", kind: "networkInterfaces" });
   await Deno.permissions.query({ name: "sys", kind: "systemMemoryInfo" });
   await Deno.permissions.query({ name: "sys", kind: "hostname" });
diff --git a/cli/tsc/diagnostics.rs b/cli/tsc/diagnostics.rs
index 4413398c2..8323fd7ac 100644
--- a/cli/tsc/diagnostics.rs
+++ b/cli/tsc/diagnostics.rs
@@ -46,6 +46,7 @@ const UNSTABLE_DENO_PROPS: &[&str] = &[
   "ServeInit",
   "ServeTlsInit",
   "Handler",
+  "osUptime",
 ];
 
 static MSG_MISSING_PROPERTY_DENO: Lazy<Regex> = Lazy::new(|| {
diff --git a/cli/tsc/dts/lib.deno.ns.d.ts b/cli/tsc/dts/lib.deno.ns.d.ts
index fa68dc1bd..4dafd7388 100644
--- a/cli/tsc/dts/lib.deno.ns.d.ts
+++ b/cli/tsc/dts/lib.deno.ns.d.ts
@@ -4120,6 +4120,7 @@ declare namespace Deno {
       | "systemMemoryInfo"
       | "networkInterfaces"
       | "osRelease"
+      | "osUptime"
       | "uid"
       | "gid";
   }
diff --git a/cli/tsc/dts/lib.deno.unstable.d.ts b/cli/tsc/dts/lib.deno.unstable.d.ts
index f1b8d99e9..77d350503 100644
--- a/cli/tsc/dts/lib.deno.unstable.d.ts
+++ b/cli/tsc/dts/lib.deno.unstable.d.ts
@@ -1691,6 +1691,21 @@ declare namespace Deno {
     /** The buffered output from the child process' `stderr`. */
     readonly stderr: Uint8Array;
   }
+
+  /** **UNSTABLE**: New API, yet to be vetted.
+   *
+   * Returns the Operating System uptime in number of seconds.
+   *
+   * ```ts
+   * console.log(Deno.osUptime());
+   * ```
+   *
+   * Requires `allow-sys` permission.
+   *
+   * @tags allow-sys
+   * @category Runtime Environment
+   */
+  export function osUptime(): number;
 }
 
 /** **UNSTABLE**: New API, yet to be vetted.