diff --git a/.gitignore b/.gitignore
index 1ba24b87..af701185 100644
--- a/.gitignore
+++ b/.gitignore
@@ -15,3 +15,4 @@ compiler/**/*.js
 .*.generated.ts
 .tmp/
 .DS_Store
+.build_cache/
diff --git a/scripts/authors.sh b/scripts/authors.sh
index d0d9ead4..415d1d84 100755
--- a/scripts/authors.sh
+++ b/scripts/authors.sh
@@ -4,10 +4,18 @@ set -e
 err() { echo "error: line $(caller)"; }
 trap err ERR
 
+mkdir -p .build_cache
 cd src/static
 
 authors="../../build/static/authors.html"
 
 sed "/REPLACETHIS/,$ d" authors.html > "$authors"
-git shortlog -sn HEAD | cut -c8- | awk '!seen[$0]++' | sed 's/^/<p>/' | sed 's/$/<\/p>/' >> "$authors"
+
+# If we're in a git repo, refresh the cache
+if [ -d "../../.git/" ]; then
+    git shortlog -sn HEAD | cut -c8- | awk '!seen[$0]++' | sed 's/^/<p>/' | sed 's/$/<\/p>/' > ../../.build_cache/authors
+fi
+
+cat ../../.build_cache/authors >> "$authors"
+
 sed "1,/REPLACETHIS/ d" authors.html >> "$authors"
diff --git a/scripts/sign b/scripts/sign
index 194c3187..25bf30c3 100755
--- a/scripts/sign
+++ b/scripts/sign
@@ -4,7 +4,7 @@ set -e
 
 sign_and_submit() {
     # Don't trust the return value of web-ext sign.
-    (source AMOKEYS && (web-ext sign -s build --api-key $AMOKEY --api-secret $AMOSECRET "$@" || true))
+    (source AMOKEYS && (yarn run web-ext sign -s build --api-key "$AMOKEY" --api-secret "$AMOSECRET" "$@" || true))
 }
 
 publish_beta_nonewtab() {
@@ -23,6 +23,7 @@ publish_beta() {
     scripts/version.js beta
     sed 's/"name": "Tridactyl"/"name": "Tridactyl: Beta"/' -i build/manifest.json
     sign_and_submit
+    tar --exclude-from=<(.grep -v .build_cache/ .gitignore) --exclude-vcs -czf ../../public_html/betas/tridactyl_source_beta.tar.gz .
 }
 
 build_no_sign_beta(){
@@ -31,9 +32,9 @@ build_no_sign_beta(){
     scripts/version.js beta
     sed 's/"name": "Tridactyl"/"name": "Tridactyl: Beta"/' -i build/manifest.json
     mkdir -p web-ext-artifacts
-    $(yarn bin)/web-ext build --source-dir ./build --overwrite-dest
+    yarn run web-ext build --source-dir ./build --overwrite-dest
     for f in web-ext-artifacts/*.zip; do
-        mv $f ${f%.zip}.xpi
+        mv "$f" "${f%.zip}".xpi
     done
 }
 
@@ -42,9 +43,9 @@ build_no_sign_stable(){
     yarn run build --no-native
     sed 's/tridactyl.vim.betas@cmcaine/tridactyl.vim@cmcaine/' -i build/manifest.json
     mkdir -p web-ext-artifacts
-    $(yarn bin)/web-ext build --source-dir ./build --overwrite-dest
+    yarn run web-ext build --source-dir ./build --overwrite-dest
     for f in web-ext-artifacts/*.zip; do
-        mv $f ${f%.zip}.xpi
+        mv "$f" "${f%.zip}".xpi
     done
 }
 
@@ -53,7 +54,7 @@ publish_stable() {
     yarn run build --no-native
     sed 's/tridactyl.vim.betas@cmcaine/tridactyl.vim@cmcaine/' -i build/manifest.json
     sign_and_submit
-    tar --exclude-from=.gitignore -czf ../../public_html/betas/tridactyl_source.tar.gz .
+    tar --exclude-from=<(grep -v .build_cache/ .gitignore) --exclude-vcs -czf ../../public_html/betas/tridactyl_source.tar.gz .
 }
 
 case $1 in
@@ -61,5 +62,6 @@ case $1 in
     nosignstable) build_no_sign_stable;;
     nosignbeta) build_no_sign_beta;;
     nonewtab) publish_beta_nonewtab;;
-    *|beta) publish_beta;;
+    beta) publish_beta;;
+    *) publish_beta;;
 esac
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