diff --git a/scripts/version.js b/scripts/version.js
index d153ab1b..301e1aaf 100755
--- a/scripts/version.js
+++ b/scripts/version.js
@@ -1,6 +1,7 @@
 #!/usr/bin/env node
 
 const { exec } = require("child_process")
+const fs = require("fs")
 
 function bump_version(versionstr, component = 2) {
     const versionarr = versionstr.split(".")
@@ -12,21 +13,37 @@ function bump_version(versionstr, component = 2) {
 }
 
 async function add_beta(versionstr) {
-    return new Promise((resolve, err) => {
-        exec("git rev-list --count HEAD", (execerr, stdout, stderr) => {
-            if (execerr) err(execerr)
-            resolve(versionstr + "pre" + stdout.trim())
+    await fs.promises.mkdir(".build_cache", {recursive: true})
+    try {
+        await fs.promises.access(".git")
+        await new Promise((resolve, err) => {
+            exec("git rev-list --count HEAD > .build_cache/count", (execerr, stdout, stderr) => {
+                if (execerr) err(execerr)
+                resolve(stdout.trim())
+            })
         })
-    })
+    }
+    catch {
+        ; // Not in a git directory - don't do anything
+    }
+    return versionstr + "pre" + (await fs.promises.readFile(".build_cache/count", {encoding: "utf8"})).trim()
 }
 
 async function get_hash() {
-    return new Promise((resolve, err) => {
-        exec("git rev-parse --short HEAD", (execerr, stdout, stderr) => {
-            if (execerr) err(execerr)
-            resolve(stdout.trim())
+    await fs.promises.mkdir(".build_cache", {recursive: true})
+    try {
+        await fs.promises.access(".git")
+        await new Promise((resolve, err) => {
+            exec("git rev-parse --short HEAD > .build_cache/hash", (execerr, stdout, stderr) => {
+                if (execerr) err(execerr)
+                resolve(stdout.trim())
+            })
         })
-    })
+    }
+    catch {
+        ; // Not in a git directory - don't do anything
+    }
+    return (await fs.promises.readFile(".build_cache/hash", {encoding: "utf8"})).trim()
 }
 
 function make_update_json(versionstr) {
@@ -102,7 +119,7 @@ async function main() {
                     make_update_json(manifest.version),
                 )
             } catch(e) {
-                console.warn("updates.json wasn't updated: " + e)
+                console.warn("Unless you're the buildbot, ignore this error: " + e)
             }
 
             // Save manifest.json