diff --git a/api/api.go b/api/api.go
index b13b40c1..8bd0b104 100644
--- a/api/api.go
+++ b/api/api.go
@@ -285,33 +285,11 @@ func showPackages(c *gin.Context, reflist *deb.PackageRefList, collectionFactory
 
 	// filter packages by version
 	if c.Request.URL.Query().Get("maximumVersion") == "1" {
-		list.PrepareIndex()
-		_ = list.ForEach(func(p *deb.Package) error {
-			versionQ, err := query.Parse(fmt.Sprintf("Name (%s), $Version (<= %s)", p.Name, p.Version))
-			if err != nil {
-				fmt.Println("filter packages by version, query string parse err: ", err)
-				_ = c.AbortWithError(500, fmt.Errorf("unable to parse %s maximum version query string: %s", p.Name, err))
-			} else {
-				tmpList, err := list.Filter(deb.FilterOptions{
-					Queries: []deb.PackageQuery{versionQ},
-				})
-
-				if err == nil {
-					if tmpList.Len() > 0 {
-						_ = tmpList.ForEach(func(tp *deb.Package) error {
-							list.Remove(tp)
-							return nil
-						})
-						_ = list.Add(p)
-					}
-				} else {
-					fmt.Println("filter packages by version, filter err: ", err)
-					_ = c.AbortWithError(500, fmt.Errorf("unable to get %s maximum version: %s", p.Name, err))
-				}
-			}
-
-			return nil
-		})
+		list, err = list.FilterLatest(1)
+		if err != nil {
+			AbortWithJSONError(c, 500, fmt.Errorf("unable to filter latest packages: %s", err))
+			return
+		}
 	}
 
 	if c.Request.URL.Query().Get("format") == "details" {
diff --git a/api/packages_maximum_version_test.go b/api/packages_maximum_version_test.go
new file mode 100644
index 00000000..0a46a271
--- /dev/null
+++ b/api/packages_maximum_version_test.go
@@ -0,0 +1,112 @@
+package api
+
+import (
+	"encoding/json"
+	"net/http/httptest"
+	"reflect"
+	"sort"
+	"testing"
+
+	"github.com/aptly-dev/aptly/database/goleveldb"
+	"github.com/aptly-dev/aptly/deb"
+	"github.com/gin-gonic/gin"
+)
+
+// Exercise the common API listing handler with persisted packages, checking
+// both reference and detailed JSON responses independently of response order.
+func TestPackagesMaximumVersionArchitectureVariant(t *testing.T) {
+	pkg := func(arch, variant, version string) *deb.Package {
+		stanza := deb.Stanza{"Package": "example", "Version": version, "Architecture": arch}
+		if variant != "" {
+			stanza["Architecture-Variant"] = variant
+		}
+		return deb.NewPackageFromControlFile(stanza)
+	}
+	n1, n3 := pkg("amd64", "", "1"), pkg("amd64", "", "3")
+	v1, v2 := pkg("amd64", "amd64v3", "1"), pkg("amd64", "amd64v3", "2")
+	a1, a4 := pkg("arm64", "", "1"), pkg("arm64", "", "4")
+	all := []*deb.Package{n1, n3, v1, v2, a1, a4}
+	cases := []struct {
+		name, option string
+		input, want  []*deb.Package
+	}{
+		{"same_version", "1", []*deb.Package{n1, v1}, []*deb.Package{n1, v1}},
+		{"independent_latest", "1", []*deb.Package{n1, n3, v1, v2}, []*deb.Package{n3, v2}},
+		{"ordinary_multi_architecture", "1", []*deb.Package{n1, n3, a1, a4}, []*deb.Package{n3, a4}},
+		{"ordinary_single_architecture", "1", []*deb.Package{n1, n3}, []*deb.Package{n3}},
+		{"disabled_absent", "", all, all},
+		{"disabled_zero", "0", all, all},
+		{"empty", "1", nil, nil},
+	}
+	for _, tc := range cases {
+		for _, format := range []string{"refs", "details"} {
+			t.Run(tc.name+"/"+format, func(t *testing.T) {
+				db, err := goleveldb.NewOpenDB(t.TempDir())
+				if err != nil {
+					t.Fatal(err)
+				}
+				t.Cleanup(func() {
+					if err := db.Close(); err != nil {
+						t.Error(err)
+					}
+				})
+				factory := deb.NewCollectionFactory(db)
+				list := deb.NewPackageList()
+				for _, p := range tc.input {
+					// Update offloads metadata; use a fresh package for each database.
+					p := pkg(p.Architecture, p.ArchitectureVariant, p.Version)
+					if err := factory.PackageCollection().Update(p); err != nil {
+						t.Fatal(err)
+					}
+					if err := list.Add(p); err != nil {
+						t.Fatal(err)
+					}
+				}
+				refs := deb.NewPackageRefListFromPackageList(list)
+				url := "/api/packages?format=" + format
+				if tc.option != "" {
+					url += "&maximumVersion=" + tc.option
+				}
+				response := httptest.NewRecorder()
+				c, _ := gin.CreateTestContext(response)
+				c.Request = httptest.NewRequest("GET", url, nil)
+				showPackages(c, refs, deb.NewCollectionFactory(db))
+				if response.Code != 200 {
+					t.Fatalf("status %d: %s", response.Code, response.Body.String())
+				}
+				got := []string{}
+				if format == "details" {
+					var details []map[string]string
+					if err := json.Unmarshal(response.Body.Bytes(), &details); err != nil {
+						t.Fatal(err)
+					}
+					for _, detail := range details {
+						got = append(got, detail["Key"])
+						// Metadata must remain separate from the identity encoded in Key.
+						for _, p := range tc.want {
+							if detail["Key"] == string(p.Key("")) {
+								if detail["Architecture"] != p.Architecture || detail["Architecture-Variant"] != p.ArchitectureVariant || detail["ShortKey"] != string(p.ShortKey("")) {
+									t.Errorf("incorrect package metadata: %v", detail)
+								}
+							}
+						}
+					}
+				} else if err := json.Unmarshal(response.Body.Bytes(), &got); err != nil {
+					t.Fatal(err)
+				}
+				want := []string{}
+				for _, p := range tc.want {
+					want = append(want, string(p.Key("")))
+				}
+				sort.Strings(got)
+				sort.Strings(want)
+				if !reflect.DeepEqual(got, want) {
+					t.Errorf("package references:\n got %v\nwant %v", got, want)
+				}
+				if !reflect.DeepEqual(refs.Strings(), deb.NewPackageRefListFromPackageList(list).Strings()) {
+					t.Error("listing mutated source references")
+				}
+			})
+		}
+	}
+}