diff --git a/REGRESSION.md b/REGRESSION.md
index 472264d..d6bcced 100644
--- a/REGRESSION.md
+++ b/REGRESSION.md
@@ -1,7 +1,7 @@
 # ETC Regression Tests 
 
-- **Build**: ETC R7 Build 11
-- **Date**: 5 July 2026
+- **Build**: ETC R7 Build 12
+- **Date**: 16 July 2026
 
 ## Desktop/Launcher Icons
 
@@ -143,9 +143,19 @@
 * [ ] Heltec v4 PnP (/dev/et-lora)
   * [ ] Offline firmware: rnodeconf --autoinstall --nocheck --fw-version 1.86 
 * [ ] et-reticulum
-  * [ ] All blueprints
+  * [ ] rnode blueprint
+  * [ ] packet radio blueprint
+  * [ ] transport blueprint
+  * [ ] modem73 blueprint
+  * [ ] local network blueprint
+  * [ ] internet blueprint
   * [ ] All permutations of radios and LoRa connected/disconnected
 
+## Modems
+
+* [ ] modem73
+* [ ] mercury
+
 ## Email
 
 * [ ] Thunderbird installed
diff --git a/scripts/install-mercury.sh b/scripts/install-mercury.sh
new file mode 100755
index 0000000..aed903c
--- /dev/null
+++ b/scripts/install-mercury.sh
@@ -0,0 +1,36 @@
+#!/bin/bash
+# Author  : Gaston Gonzalez
+# Date    : 17 July 2025
+# Purpose : Builds and installs the Mercury HF modem
+set -e
+trap 'last_command=$current_command; current_command=$BASH_COMMAND' DEBUG
+trap 'et-log "\"${last_command}\" command failed with exit code $?."' ERR
+
+. ./env.sh
+
+APP="mercury"
+VERSION="1.9.9"
+APP_AND_VERSION="${APP}-${VERSION}"
+GIT_TAG="v${VERSION}"
+GIT_URL="https://github.com/Rhizomatica/mercury.git"
+GIT_WORKSPACE="mercury"
+INSTALL_DIR="/opt/${APP_AND_VERSION}"
+LINK_PATH="/opt/${APP}"
+
+et-log "Installing ${APP} ${VERSION}"
+
+CWD_DIR=`pwd`
+
+cd ${ET_SRC_DIR}
+[[ ! -e ${GIT_WORKSPACE} ]] && git clone ${GIT_URL} ${GIT_WORKSPACE}
+
+cd ${GIT_WORKSPACE} && git checkout ${GIT_TAG}
+
+make && make install prefix="${INSTALL_DIR}"
+
+[[ -e ${LINK_PATH} ]] && rm ${LINK_PATH}
+ln -v -s ${INSTALL_DIR} ${LINK_PATH}
+
+stow -v -d /opt ${APP} -t /usr/local
+
+cd ${CWD}
diff --git a/scripts/install.sh b/scripts/install.sh
index 3147437..95a0841 100755
--- a/scripts/install.sh
+++ b/scripts/install.sh
@@ -2,7 +2,8 @@
 #
 # Author  : Gaston Gonzalez
 # Date    : 16 March 2024
-# Updated : 5 July 2026 # Purpose : Main installer for EmComm Tools Community (ETC)
+# Updated : 16 July 2026
+# Purpose : Main installer for EmComm Tools Community (ETC)
 
 . ./env.sh
 . ./functions.sh
@@ -121,6 +122,7 @@ exitIfNotRoot
 ./install-reticulum.sh
 ./install-meshchat.sh
 ./install-modem73.sh
+./install-mercury.sh
 ./install-offline-rnode-firmware.sh
 
 # Debrand Ubuntu
diff --git a/tests/test-mercury.sh b/tests/test-mercury.sh
new file mode 100755
index 0000000..740d9c9
--- /dev/null
+++ b/tests/test-mercury.sh
@@ -0,0 +1,7 @@
+#!/bin/bash
+# Author   : Gaston Gonzalez
+# Date     : 16 July 2026
+# Purpose  : Test Mercury installation
+
+OUT=$(which mercury)
+exit $?