Waybar: add new memory widget

home/.config/waybar/config.jsonc

@@ -23,7 +23,7 @@
         "network",
         "power-profiles-daemon",
         "cpu",
-        //"memory",
+        "custom/memtmp",
         //"temperature",
         "backlight",
         //"sway/language",
@@ -169,6 +169,13 @@
         "tooltip": false,
         "on-click": "alacritty -e /home/tgrosinger/.local/share/mise/shims/btop"
     },
+    "custom/memtmp": {
+        "exec": "bash $HOME/.config/waybar/memtmp.sh",
+        "return-type": "json",
+        "interval": 5,
+        "format": "{}",
+        "on-click": "alacritty -e /home/tgrosinger/.local/share/mise/shims/btop"
+    },
     "memory": {
         "format": "{}% "
     },

home/.config/waybar/memtmp.sh

@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+# Waybar custom module: available RAM (GiB) and current /tmp usage.
+#
+# Available RAM uses MemAvailable, the kernel's honest "allocatable without
+# swapping" figure. /tmp is tmpfs, so its used space is live RAM consumption;
+# df -h auto-scales the unit (it is usually in the MB range).
+set -euo pipefail
+
+MEM_ICON=$''
+TMP_ICON=$''
+
+avail_gib=$(awk '/^MemAvailable:/ {printf "%.1f", $2/1048576}' /proc/meminfo)
+read -r tmp_used tmp_size < <(df -h --output=used,size /tmp | awk 'NR==2 {print $1, $2}')
+
+printf '{"text":"%sG %s  %s %s","tooltip":"RAM available: %s GiB\\n/tmp used: %s of %s"}\n' \
+    "$avail_gib" "$MEM_ICON" "$tmp_used" "$TMP_ICON" \
+    "$avail_gib" "$tmp_used" "$tmp_size"

home/.config/waybar/style.css

@@ -1,7 +1,7 @@
 @import "latte.css";
 
 * {
-    font-family: 'JetBrainsMono';
+    font-family: 'JetBrainsMono Nerd Font';
     font-size: 13px;
 }
 
@@ -89,6 +89,7 @@ button:hover {
 #battery,
 #cpu,
 #memory,
+#custom-memtmp,
 #disk,
 #temperature,
 #backlight,