diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 0000000..4a181d2
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,19 @@
+version: 2
+updates:
+- package-ecosystem: gomod
+  directory: "/entrypoint"
+  schedule:
+    interval: daily
+    time: "10:00"
+  open-pull-requests-limit: 10
+  ignore:
+  - dependency-name: github.com/otiai10/copy
+    versions:
+    - 1.4.2
+    - 1.5.1
+- package-ecosystem: docker
+  directory: "/"
+  schedule:
+    interval: daily
+    time: "10:00"
+  open-pull-requests-limit: 10
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
new file mode 100644
index 0000000..7c20340
--- /dev/null
+++ b/.github/workflows/build.yml
@@ -0,0 +1,22 @@
+name: Build
+
+on:
+  push:
+    branches:
+      - master
+  pull_request: {}
+
+jobs:
+  build:
+    name: build
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout HEAD
+        uses: actions/checkout@v1
+
+      - name: Icinga 2
+        run: git clone https://github.com/Icinga/icinga2.git
+
+      - name: Build
+        run: ./build.bash ./icinga2
diff --git a/README.md b/README.md
index 51a347a..e70a816 100644
--- a/README.md
+++ b/README.md
@@ -65,6 +65,10 @@ To configure it, do one of the following:
   on which configuration files there are.
 * Provide environment variables as shown above.
 
+To notify by e-mail, provide an [msmtp configuration] - either
+by mounting the `/etc/msmtprc` file or by specifying the desired content
+of `~icinga/.msmtprc` via the environment variable `MSMTPRC`.
+
 ### Environment variables
 
 Most of the following variables correspond to
@@ -107,7 +111,15 @@ git clone https://github.com/Icinga/icinga2.git
 ./build.bash ./icinga2
 ```
 
+In order to run the script on macOS, [coreutils] must be installed:
+
+* Install [Homebrew]
+* Run `brew install coreutils`
+
 [Icinga 2]: https://github.com/Icinga/icinga2
 [Docker]: https://www.docker.com
 [Icinga 2 configuration documentation]: https://icinga.com/docs/icinga2/latest/doc/04-configuration/
+[msmtp configuration]: https://wiki.archlinux.org/index.php/Msmtp
 [node setup command documentation]: https://icinga.com/docs/icinga2/latest/doc/06-distributed-monitoring/#node-setup
+[Homebrew]: https://brew.sh/
+[coreutils]: https://formulae.brew.sh/formula/coreutils
diff --git a/deps.Dockerfile b/deps.Dockerfile
index 73734e4..2417ed1 100644
--- a/deps.Dockerfile
+++ b/deps.Dockerfile
@@ -59,7 +59,7 @@ RUN cd /check_postgres ;\
 
 FROM debian:buster-slim
 
-RUN ["/bin/bash", "-exo", "pipefail", "-c", "export DEBIAN_FRONTEND=noninteractive; apt-get update; apt-get install --no-install-{recommends,suggests} -y dumb-init libboost-{context,coroutine,date-time,filesystem,program-options,regex,system,thread}1.67 libedit2 libmariadb3 libmoosex-role-timer-perl libpq5 libssl1.1 mailutils monitoring-plugins openssh-client openssl postfix libcap2-bin; apt-get clean; rm -vrf /var/lib/apt/lists/*"]
+RUN ["/bin/bash", "-exo", "pipefail", "-c", "apt-get update; DEBIAN_FRONTEND=noninteractive apt-get install --no-install-{recommends,suggests} -y ca-certificates curl dumb-init libboost-{context,coroutine,date-time,filesystem,program-options,regex,system,thread}1.67 libcap2-bin libedit2 libmariadb3 libmoosex-role-timer-perl libpq5 libssl1.1 mailutils monitoring-plugins msmtp{,-mta} openssh-client openssl; apt-get clean; rm -vrf /var/lib/apt/lists/*"]
 
 COPY --from=entrypoint /entrypoint/entrypoint /entrypoint
 
diff --git a/entrypoint/go.mod b/entrypoint/go.mod
index f099074..31dad30 100644
--- a/entrypoint/go.mod
+++ b/entrypoint/go.mod
@@ -3,6 +3,6 @@ module entrypoint
 go 1.14
 
 require (
-	github.com/otiai10/copy v1.4.0
+	github.com/otiai10/copy v1.5.1
 	golang.org/x/crypto v0.0.0-20200604202706-70a84ac30bf9
 )
diff --git a/entrypoint/go.sum b/entrypoint/go.sum
index addf468..1d8db75 100644
--- a/entrypoint/go.sum
+++ b/entrypoint/go.sum
@@ -4,6 +4,10 @@ github.com/otiai10/copy v1.3.0 h1:Z0OIFgj8hyI18YVzgPXpp652vv0NggCGWaNKSPN9KU8=
 github.com/otiai10/copy v1.3.0/go.mod h1:XWfuS3CrI0R6IE0FbgHsEazaXO8G0LpMp9o8tos0x4E=
 github.com/otiai10/copy v1.4.0 h1:S9XdWuTRJ54QDIrdbPEVl/1lMwF5xOjd5AvF9S866y8=
 github.com/otiai10/copy v1.4.0/go.mod h1:XWfuS3CrI0R6IE0FbgHsEazaXO8G0LpMp9o8tos0x4E=
+github.com/otiai10/copy v1.5.0 h1:SoXDGnlTUZoqB/wSuj/Y5L6T5i6iN4YRAcMCd+JnLNU=
+github.com/otiai10/copy v1.5.0/go.mod h1:XWfuS3CrI0R6IE0FbgHsEazaXO8G0LpMp9o8tos0x4E=
+github.com/otiai10/copy v1.5.1 h1:a/cs2E1/1V0az8K5nblbl+ymEa4E11AfaOLMar8V34w=
+github.com/otiai10/copy v1.5.1/go.mod h1:XWfuS3CrI0R6IE0FbgHsEazaXO8G0LpMp9o8tos0x4E=
 github.com/otiai10/curr v0.0.0-20150429015615-9b4961190c95/go.mod h1:9qAhocn7zKJG+0mI8eUu6xqkFDYS2kb2saOteoSB3cE=
 github.com/otiai10/curr v1.0.0 h1:TJIWdbX0B+kpNagQrjgq8bCMrbhiuX73M2XwgtDMoOI=
 github.com/otiai10/curr v1.0.0/go.mod h1:LskTG5wDwr8Rs+nNQ+1LlxRjAtTZZjtJW4rMXl6j4vs=
diff --git a/entrypoint/main.go b/entrypoint/main.go
index c4bb0da..77b50bd 100644
--- a/entrypoint/main.go
+++ b/entrypoint/main.go
@@ -19,6 +19,7 @@ import (
 
 const ca = "/var/lib/icinga2/certs/ca.crt"
 const crtMode = 0640
+const mSmtpRc = "/var/lib/icinga2/.msmtprc"
 
 func main() {
 	if err := entrypoint(); err != nil {
@@ -122,6 +123,14 @@ func entrypoint() error {
 			}
 		}
 
+		if mSmtpCfg, ok := os.LookupEnv("MSMTPRC"); ok {
+			logf(info, "Writing %#v", mSmtpRc)
+
+			if errWF := ioutil.WriteFile(mSmtpRc, []byte(mSmtpCfg), 0644); errWF != nil {
+				return errWF
+			}
+		}
+
 		command = append([]string{"dumb-init", "-c", "--"}, command...)
 	}