diff --git a/external.go b/external.go
index f769125..b493317 100644
--- a/external.go
+++ b/external.go
@@ -1,3 +1,4 @@
+//go:build external
 // +build external
 
 package main
@@ -12,6 +13,8 @@ import (
 
 const binaryType = "external"
 
+func BuildTagsExternal() { buildTags = append(buildTags, "external") }
+
 var localFS dirFS
 var langFS dirFS
 
diff --git a/html/admin.html b/html/admin.html
index 497706d..7eaea80 100644
--- a/html/admin.html
+++ b/html/admin.html
@@ -51,6 +51,7 @@
                 <p>{{ .strings.commitNoun }} <span class="text-black dark:text-white font-mono bg-inherit">{{ .commit }}</span></p>
                 <p>{{ .strings.buildTime }} <span class="text-black dark:text-white font-mono bg-inherit">{{ .buildTime }}</span></p>
                 <p>{{ .strings.builtBy }} <span class="text-black dark:text-white font-mono bg-inherit">{{ .builtBy }}</span></p>
+                <p>{{ .strings.buildTags }} <span class="text-black dark:text-white font-mono bg-inherit">{{ .buildTags }}</span></p>
                 <div class="flex flex-row flex-wrap gap-2 my-2">
                     <a class="button ~neutral lang-link" href="https://github.com/hrfee/jfa-go"><i class="ri-github-line mr-2"></i>github</a>
                     <a class="button ~urge lang-link" href="https://wiki.jfa-go.com">wiki/docs</a>
diff --git a/internal.go b/internal.go
index a2fc105..050e346 100644
--- a/internal.go
+++ b/internal.go
@@ -1,3 +1,4 @@
+//go:build !external
 // +build !external
 
 package main
@@ -10,6 +11,8 @@ import (
 
 const binaryType = "internal"
 
+func BuildTagsExternal() {}
+
 //go:embed data data/html data/web data/web/css data/web/js
 var loFS embed.FS
 
diff --git a/lang/admin/en-us.json b/lang/admin/en-us.json
index 8514dbc..eed6603 100644
--- a/lang/admin/en-us.json
+++ b/lang/admin/en-us.json
@@ -146,6 +146,7 @@
         "postSignupCardDescription": "Card shown to user after signing up. Overrides \"Success Message\". Overriden by \"Auto redirect on success\" setting.",
         "buildTime": "Build Time",  
         "builtBy": "Built By",
+        "buildTags": "Build Tags",
         "loginNotAdmin": "Not an Admin?",
         "referrer": "Referrer",
         "accountLinked": "{contactMethod} linked: {user}",
diff --git a/main.go b/main.go
index bb17766..98e6698 100644
--- a/main.go
+++ b/main.go
@@ -60,6 +60,7 @@ var (
 	commit               string
 	buildTimeUnix        string
 	builtBy              string
+	buildTags            []string
 	_LOADBAK             *string
 	LOADBAK              = ""
 )
@@ -740,6 +741,11 @@ func printVersion() {
 const SYSTEMD_SERVICE = "jfa-go.service"
 
 func main() {
+	// Generate list of "-tags" for about page.
+	BuildTagsE2EE()
+	BuildTagsTray()
+	BuildTagsExternal()
+
 	f, err := logOutput()
 	if err != nil {
 		fmt.Printf(lm.FailedLogging, err)
diff --git a/matrix_crypto.go b/matrix_crypto.go
index 19f7b92..30416ea 100644
--- a/matrix_crypto.go
+++ b/matrix_crypto.go
@@ -16,6 +16,10 @@ type Crypto struct {
 	helper *cryptohelper.CryptoHelper
 }
 
+func BuildTagsE2EE() {
+	buildTags = append(buildTags, "e2ee")
+}
+
 func MatrixE2EE() bool { return true }
 
 func InitMatrixCrypto(d *MatrixDaemon) error {
diff --git a/matrix_nocrypto.go b/matrix_nocrypto.go
index e46d621..8a2f84e 100644
--- a/matrix_nocrypto.go
+++ b/matrix_nocrypto.go
@@ -7,6 +7,8 @@ import "maunium.net/go/mautrix/id"
 
 type Crypto struct{}
 
+func BuildTagsE2EE() {}
+
 func MatrixE2EE() bool { return false }
 
 func InitMatrixCrypto(d *MatrixDaemon) (err error) {
diff --git a/notray.go b/notray.go
index b51efca..369dafd 100644
--- a/notray.go
+++ b/notray.go
@@ -1,9 +1,12 @@
+//go:build !tray
 // +build !tray
 
 package main
 
 var TRAY = false
 
+func BuildTagsTray() {}
+
 func RunTray() {}
 
 func QuitTray() {}
diff --git a/tray.go b/tray.go
index 135a06b..7d1bc4f 100644
--- a/tray.go
+++ b/tray.go
@@ -15,6 +15,10 @@ import (
 
 var TRAY = true
 
+func BuildTagsTray() {
+	buildTags = append(buildTags, "tray")
+}
+
 func RunTray() {
 	systray.Run(onReady, onExit)
 }
diff --git a/views.go b/views.go
index 4e36901..76169ed 100644
--- a/views.go
+++ b/views.go
@@ -174,6 +174,7 @@ func (app *appContext) AdminPage(gc *gin.Context) {
 		"commit":            commit,
 		"buildTime":         buildTime,
 		"builtBy":           builtBy,
+		"buildTags":         buildTags,
 		"username":          !app.config.Section("email").Key("no_username").MustBool(false),
 		"strings":           app.storage.lang.Admin[lang].Strings,
 		"quantityStrings":   app.storage.lang.Admin[lang].QuantityStrings,