diff --git a/experiments/layered-server-config/README.md b/experiments/layered-server-config/README.md
new file mode 100644
index 0000000..3560363
--- /dev/null
+++ b/experiments/layered-server-config/README.md
@@ -0,0 +1,3 @@
+# Experimenting with service groups
+
+    syndicate-server -c ./boot
diff --git a/experiments/layered-server-config/boot/010-milestone.pr b/experiments/layered-server-config/boot/010-milestone.pr
new file mode 100644
index 0000000..9e512c3
--- /dev/null
+++ b/experiments/layered-server-config/boot/010-milestone.pr
@@ -0,0 +1,10 @@
+; To "run" a milestone service,
+;  - assert that it is both started and ready
+;  - that's it!
+;
+? <run-service <milestone ?m>> [
+  <service-state <milestone $m> started>
+  <service-state <milestone $m> ready>
+  $log ! <log "-" { service: <milestone $m> state: up }>
+  ?- <log "-" { service: <milestone $m> state: down }>
+]
diff --git a/experiments/layered-server-config/boot/010-service-state-up.pr b/experiments/layered-server-config/boot/010-service-state-up.pr
new file mode 100644
index 0000000..e9fd2b2
--- /dev/null
+++ b/experiments/layered-server-config/boot/010-service-state-up.pr
@@ -0,0 +1,4 @@
+; To the usual suite of service states we add `up`, meaning "either `ready` or `complete`".
+;
+? <service-state ?x ready> <service-state $x up>
+? <service-state ?x complete> <service-state $x up>
diff --git a/experiments/layered-server-config/boot/020-load-system-layer.pr b/experiments/layered-server-config/boot/020-load-system-layer.pr
new file mode 100644
index 0000000..8daa3e5
--- /dev/null
+++ b/experiments/layered-server-config/boot/020-load-system-layer.pr
@@ -0,0 +1,28 @@
+; Attenuate `$config` by rewriting plain `require-service` assertions to
+; `require-system-service` assertions. Allow all other assertions through.
+;
+let ?sys = <* $config [
+  <rewrite <require-service ?s> <require-system-service $s>>
+  <filter _>
+]>
+
+; Give meaning to `require-system-service`: it is an ordinary `require-service`, plus a
+; declaration that the `system-layer` milestone depends on the service.
+;
+? <require-system-service ?s> [
+  <depends-on <milestone system-layer> <service-state $s up>>
+  <require-service $s>
+]
+
+; Load config in the `system-layer` directory, using the wrapped `config` so that all plain
+; services required are changed to be *system* services.
+;
+<require-service <config-watcher "./system-layer" {
+  config: $sys
+  gatekeeper: $gatekeeper
+  log: $log
+}>>
+
+; In addition, require the `system-layer` milestone explicitly.
+;
+<require-service <milestone system-layer>>
diff --git a/experiments/layered-server-config/boot/030-load-services.pr b/experiments/layered-server-config/boot/030-load-services.pr
new file mode 100644
index 0000000..5893dfb
--- /dev/null
+++ b/experiments/layered-server-config/boot/030-load-services.pr
@@ -0,0 +1,26 @@
+; Attenuate `$config` by rewriting plain `require-service` assertions to
+; `require-basic-service` assertions. Allow all other assertions through.
+;
+let ?basic = <* $config [
+  <rewrite <require-service ?s> <require-basic-service $s>>
+  <filter _>
+]>
+
+; Give meaning to `require-basic-service`: it is an ordinary `require-service`, plus a
+; declaration that the service depends on the `system-layer` milestone.
+;
+? <require-basic-service ?s> [
+  <depends-on $s <service-state <milestone system-layer> up>>
+  <require-service $s>
+]
+
+; Once we see that the `system-layer` milestone is ready, start processing the `services`
+; directory.
+;
+? <service-state <milestone system-layer> up> [
+  <require-service <config-watcher "./services" {
+    config: $basic
+    gatekeeper: $gatekeeper
+    log: $log
+  }>>
+]
diff --git a/experiments/layered-server-config/services/mock-httpd.pr b/experiments/layered-server-config/services/mock-httpd.pr
new file mode 100644
index 0000000..1c8b7a0
--- /dev/null
+++ b/experiments/layered-server-config/services/mock-httpd.pr
@@ -0,0 +1,4 @@
+<require-service <daemon httpd>>
+
+<daemon httpd <one-shot "echo httpd">>
+
diff --git a/experiments/layered-server-config/start.sh b/experiments/layered-server-config/start.sh
new file mode 100755
index 0000000..4fbf87f
--- /dev/null
+++ b/experiments/layered-server-config/start.sh
@@ -0,0 +1,3 @@
+#!/bin/sh
+make -C ~/src/syndicate-rs
+~/src/syndicate-rs/target/debug/syndicate-server -c boot/
diff --git a/experiments/layered-server-config/system-layer/mock-eudev.pr b/experiments/layered-server-config/system-layer/mock-eudev.pr
new file mode 100644
index 0000000..a32e1d3
--- /dev/null
+++ b/experiments/layered-server-config/system-layer/mock-eudev.pr
@@ -0,0 +1,7 @@
+<require-service <daemon eudev>>
+<require-service <daemon eudev-initial-scan>>
+
+<daemon eudev <one-shot "echo eudev">>
+
+<depends-on <daemon eudev-initial-scan> <service-state <daemon eudev> up>>
+<daemon eudev-initial-scan <one-shot "echo eudev-initial-scan">>