diff --git a/.github/buildomat/jobs/multicast-test.sh b/.github/buildomat/jobs/multicast-test.sh
deleted file mode 100755
index a6e1669f..00000000
--- a/.github/buildomat/jobs/multicast-test.sh
+++ /dev/null
@@ -1,34 +0,0 @@
-#!/bin/bash
-#:
-#: name = "multicast-test"
-#: variety = "basic"
-#: target = "ubuntu-22.04"
-#: rust_toolchain = true
-#:
-#: output_rules = [
-#:   "/work/simulator.log",
-#:   "/work/dpd.log",
-#: ]
-#:
-
-#### >>>>>>>>>>>>>>>>>>>>>>>>>>>> Local Usage >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
-####
-#### The following environment variables are useful.
-####
-####   - JUST_TEST=1        Just runs the tests, skipping system prep.
-####   - TESTNAME='$name'   Will just run the specified test.
-####   - STARTUP_TIMEOUT=n  Seconds to wait for tofino-model/dpd to start.
-####                        Defaults to 15.
-####   - NOBUILD=1          Don't build sidecar.p4 (in case you've already
-####                        built it)
-####
-#### <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
-
-export RUST_BACKTRACE=1
-
-set -o errexit
-set -o pipefail
-set -o xtrace
-
-export MULTICAST=1
-source .github/buildomat/packet-test-common.sh
diff --git a/.github/buildomat/packet-test-common.sh b/.github/buildomat/packet-test-common.sh
index 44855110..e72d1fb0 100755
--- a/.github/buildomat/packet-test-common.sh
+++ b/.github/buildomat/packet-test-common.sh
@@ -10,15 +10,7 @@ STARTUP_TIMEOUT=${STARTUP_TIMEOUT:=120}
 DENDRITE_TEST_HOST=${DENDRITE_TEST_HOST:="[::1]"}
 DENDRITE_TEST_VERBOSITY=${DENDRITE_TEST_VERBOSITY:=3}
 
-if [ "$MULTICAST" == "" ]; then
-    BUILD_FEATURES=tofino_asic
-    CODEGEN_FEATURES=()
-    SWADM_FEATURES=()
-else
-    BUILD_FEATURES=tofino_asic,multicast
-    CODEGEN_FEATURES=(--multicast)
-    SWADM_FEATURES=(--features=multicast)
-fi
+BUILD_FEATURES=tofino_asic
 
 function cleanup {
     set +o errexit
@@ -64,7 +56,7 @@ export SDE=/opt/oxide/tofino_sde
 banner "Build"
 if [[ $NOBUILD -ne 1 ]]; then
     cargo build --features=$BUILD_FEATURES --bin dpd --bin swadm
-    cargo xtask codegen --stages "$TOFINO_STAGES" "${CODEGEN_FEATURES[@]}"
+    cargo xtask codegen --stages "$TOFINO_STAGES"
 fi
 
 banner "Test"
@@ -125,12 +117,10 @@ pushd swadm
 
 cargo test \
     --no-fail-fast \
-    "${SWADM_FEATURES[@]}" \
     -- \
     --ignored
 
 cargo test \
-    --no-fail-fast \
-    "${SWADM_FEATURES[@]}"
+    --no-fail-fast
 
 popd
diff --git a/aal/Cargo.toml b/aal/Cargo.toml
index 81ecdb6f..4452a133 100644
--- a/aal/Cargo.toml
+++ b/aal/Cargo.toml
@@ -4,6 +4,7 @@ version = "0.1.0"
 edition = "2024"
 
 [features]
+default = ["multicast"]
 multicast = []
 
 [dependencies]
diff --git a/asic/Cargo.toml b/asic/Cargo.toml
index 96d42164..14a517b0 100644
--- a/asic/Cargo.toml
+++ b/asic/Cargo.toml
@@ -4,6 +4,7 @@ version = "0.1.0"
 edition = "2024"
 
 [features]
+default = ["multicast"]
 tofino_asic = [
     "dep:lazy_static",
     "dep:transceiver-controller",
diff --git a/dpd-client/Cargo.toml b/dpd-client/Cargo.toml
index 7998da4d..e2b26661 100644
--- a/dpd-client/Cargo.toml
+++ b/dpd-client/Cargo.toml
@@ -5,6 +5,7 @@ edition = "2024"
 description = "Client library for the Dendrite data plane daemon"
 
 [features]
+default = ["multicast"]
 multicast = ["asic/multicast"]
 chaos = ["asic/chaos"]
 tofino_asic = ["asic/tofino_asic"]
diff --git a/dpd/Cargo.toml b/dpd/Cargo.toml
index 05726534..968fa6f7 100644
--- a/dpd/Cargo.toml
+++ b/dpd/Cargo.toml
@@ -5,6 +5,7 @@ authors = ["nils <nils@oxide.computer>"]
 edition = "2024"
 
 [features]
+default = ["multicast"]
 multicast = ["aal/multicast", "asic/multicast"]
 tofino_asic = ["asic/tofino_asic"]
 tofino_stub = ["asic/tofino_stub"]
diff --git a/dpd/src/mcast/mod.rs b/dpd/src/mcast/mod.rs
index 5a685415..3ac32330 100644
--- a/dpd/src/mcast/mod.rs
+++ b/dpd/src/mcast/mod.rs
@@ -2393,15 +2393,16 @@ mod tests {
             None
         );
 
-        // Vec with only Exact sources stays as-is
+        // Vec with only Exact sources is deduplicated and sorted
         let exact_sources = vec![
             IpSrc::Exact(IpAddr::V4(Ipv4Addr::new(192, 168, 1, 1))),
             IpSrc::Exact(IpAddr::V4(Ipv4Addr::new(10, 0, 0, 1))),
         ];
-        assert_eq!(
-            canonicalize_sources(Some(exact_sources.clone())),
-            Some(exact_sources)
-        );
+        let expected = vec![
+            IpSrc::Exact(IpAddr::V4(Ipv4Addr::new(10, 0, 0, 1))),
+            IpSrc::Exact(IpAddr::V4(Ipv4Addr::new(192, 168, 1, 1))),
+        ];
+        assert_eq!(canonicalize_sources(Some(exact_sources)), Some(expected));
 
         // Single Exact source stays as-is
         let single_exact = vec![IpSrc::Exact(IpAddr::V6(Ipv6Addr::new(
diff --git a/swadm/Cargo.toml b/swadm/Cargo.toml
index 57ceccdf..eabb9018 100644
--- a/swadm/Cargo.toml
+++ b/swadm/Cargo.toml
@@ -6,6 +6,7 @@ authors = ["nils <nils@oxide.computer>"]
 edition = "2024"
 
 [features]
+default = ["multicast"]
 multicast = []
 
 [dependencies]
diff --git a/xtask/src/main.rs b/xtask/src/main.rs
index f7cdda5c..bccddecb 100644
--- a/xtask/src/main.rs
+++ b/xtask/src/main.rs
@@ -80,9 +80,9 @@ enum XtaskCommands {
         #[clap(long)]
         stages: Option<u8>,
 
-        /// Include support for multicast
+        /// exclude multicast support from the P4 build
         #[clap(long)]
-        multicast: bool,
+        no_multicast: bool,
     },
     /// build an installable dataplane controller package
     Dist {
@@ -251,8 +251,8 @@ async fn main() {
     if let Err(e) = match task.subcommand {
         XtaskCommands::Openapi(external) => external
             .exec_bin("dendrite-dropshot-apis", "dendrite-dropshot-apis"),
-        XtaskCommands::Codegen { name, sde, stages, multicast } => {
-            codegen::build(name, sde, stages, multicast)
+        XtaskCommands::Codegen { name, sde, stages, no_multicast } => {
+            codegen::build(name, sde, stages, !no_multicast)
         }
         XtaskCommands::Dist { features, names, release, format } => {
             plat::dist(features, names, release, format).await