diff --git a/cmd/show.go b/cmd/show.go
index db9484d..34fe9bd 100644
--- a/cmd/show.go
+++ b/cmd/show.go
@@ -23,11 +23,8 @@ package cmd
 
 import (
 	"fmt"
-	"os"
 
 	"gitea.elkins.co/Networking/ccl/internal/pkg/config"
-	"gitea.elkins.co/Networking/ccl/internal/pkg/container"
-	toml "github.com/pelletier/go-toml"
 	"github.com/spf13/cobra"
 )
 
@@ -40,16 +37,7 @@ var showCmd = &cobra.Command{
 	Long: `Output a toml format for the listed containers, which should be adequate
 to use as a ccl config file.`,
 	Run: func(cmd *cobra.Command, args []string) {
-		type parse struct {
-			Containers []container.Container `toml:"containers,omitempty"`
-		}
-
-		conts := config.Union(args, contMask)
-		output, err := toml.Marshal(parse{conts})
-		if err != nil {
-			fmt.Println("could not marshal containers:", err)
-			os.Exit(1)
-		}
+		output := config.Show(args, contMask)
 		fmt.Fprintln(cmd.OutOrStdout(), string(output))
 	},
 }
diff --git a/internal/pkg/config/config.go b/internal/pkg/config/config.go
index 179702a..dfb436c 100644
--- a/internal/pkg/config/config.go
+++ b/internal/pkg/config/config.go
@@ -1,8 +1,12 @@
 package config
 
 import (
+	"bytes"
 	"context"
+	"fmt"
+	"net"
 	"os"
+	"sort"
 
 	"gitea.elkins.co/Networking/ccl/internal/pkg/container"
 	"gitea.elkins.co/Networking/ccl/internal/pkg/network"
@@ -10,6 +14,7 @@ import (
 	toml "github.com/pelletier/go-toml"
 	log "github.com/sirupsen/logrus"
 	"golang.org/x/exp/slices"
+	"gopkg.in/guregu/null.v4"
 )
 
 const (
@@ -60,7 +65,8 @@ func Union(ids []string, catMask []string) (conts []container.Container) {
 	}
 	if len(conts) == 0 {
 		log.WithFields(log.Fields{
-			"ids": ids,
+			"ids":     ids,
+			"catMask": catMask,
 		}).Warnln("No matching containers. If disabled, try adding -a")
 	}
 	slices.SortFunc(conts, func(a, b container.Container) bool {
@@ -75,6 +81,26 @@ func Union(ids []string, catMask []string) (conts []container.Container) {
 	return
 }
 
+func UnionNetworks(ids []string) []network.Network {
+	nets := make([]network.Network, len(Networks))
+	rejects := []int{}
+	copy(nets, Networks)
+	for i := range nets {
+		if !slices.Contains(ids, nets[i].Name) {
+			rejects = append(rejects, i)
+		}
+	}
+	// reverse the rejects list, so we can delete from the end backward
+	// and thereby not fuck up sequential indicies
+	sort.SliceStable(rejects, func(i, j int) bool {
+		return true
+	})
+	for _, j := range rejects {
+		nets = slices.Delete(nets, j, j+1)
+	}
+	return nets
+}
+
 func Init(conn context.Context) error {
 	// A parsing convenience
 	type parse struct {
@@ -100,3 +126,66 @@ func Init(conn context.Context) error {
 	})
 	return nil
 }
+
+func Show(ids []string, contMask []string) string {
+	type parse struct {
+		Containers []container.Container `toml:"containers,omitempty"`
+		Networks   []network.Network     `toml:"networks,omitempty"`
+	}
+
+	getNet := func(name string) *network.Network {
+		for i := range Networks {
+			if Networks[i].Name == name {
+				return &Networks[i]
+			}
+		}
+		return nil
+	}
+
+	ipSliceEq := func(a, b []net.IP) bool {
+		if len(a) != len(b) {
+			return false
+		}
+		for i := range a {
+			if !bytes.Equal(a[i], b[i]) {
+				return false
+			}
+		}
+		return true
+	}
+
+	conts := Union(ids, contMask)
+	// clear out values equal to the defined networks
+	for c := range conts {
+		for n := range conts[c].Networks {
+			d := getNet(conts[c].Networks[n].Name)
+			if d == nil {
+				conts[c].LogEntry().WithField("network", conts[c].Networks[n].Name).Warnln("Network defaults not defined")
+				continue
+			}
+			if conts[c].Networks[n].IPv6 == d.IPv6 {
+				conts[c].Networks[n].IPv6 = null.Bool{}
+			}
+			if ipSliceEq(conts[c].Networks[n].DNS, d.DNS) {
+				conts[c].Networks[n].DNS = nil
+			}
+		}
+	}
+	usednets := hashset.New()
+	for _, c := range conts {
+		for _, n := range c.Networks {
+			usednets.Add(n.Name)
+		}
+	}
+	for _, un := range usednets.Values() {
+		ids = append(ids, un.(string))
+	}
+	nets := UnionNetworks(ids)
+
+	output, err := toml.Marshal(parse{conts, nets})
+	if err != nil {
+		fmt.Println("could not marshal containers:", err)
+		os.Exit(1)
+	}
+	return string(output)
+}