diff --git a/internal/frontend/unit_main.go b/internal/frontend/unit_main.go
index 4ad94b3..536b224 100644
--- a/internal/frontend/unit_main.go
+++ b/internal/frontend/unit_main.go
@@ -15,6 +15,7 @@
 
 	"github.com/google/safehtml"
 	"github.com/google/safehtml/template"
+	"golang.org/x/mod/semver"
 	"golang.org/x/pkgsite/internal"
 	"golang.org/x/pkgsite/internal/derrors"
 	"golang.org/x/pkgsite/internal/experiment"
@@ -23,6 +24,7 @@
 	"golang.org/x/pkgsite/internal/log"
 	"golang.org/x/pkgsite/internal/middleware"
 	"golang.org/x/pkgsite/internal/postgres"
+	"golang.org/x/pkgsite/internal/version"
 )
 
 // MainDetails contains data needed to render the unit template.
@@ -89,6 +91,15 @@
 
 	// ExpandReadme is holds the expandable readme state.
 	ExpandReadme bool
+
+	// ModFileURL is an URL to the mod file.
+	ModFileURL string
+
+	// IsTaggedVersion is true if the version is not a psuedorelease.
+	IsTaggedVersion bool
+
+	// IsStableVersion is true if the major version is v1 or greater.
+	IsStableVersion bool
 }
 
 // File is a source file for a package.
@@ -185,6 +196,12 @@
 		}
 	}
 
+	versionType, err := version.ParseType(um.Version)
+	if err != nil {
+		return nil, err
+	}
+	isTaggedVersion := versionType != version.TypePseudo
+
 	return &MainDetails{
 		ExpandReadme:      expandReadme,
 		NestedModules:     nestedModules,
@@ -206,6 +223,9 @@
 		NumImports:        unit.NumImports,
 		ImportedByCount:   importedByCount,
 		IsPackage:         unit.IsPackage(),
+		ModFileURL:        um.SourceInfo.ModuleURL() + "/go.mod",
+		IsTaggedVersion:   isTaggedVersion,
+		IsStableVersion:   semver.Major(um.Version) != "v0",
 	}, nil
 }
 
diff --git a/internal/postgres/path_test.go b/internal/postgres/path_test.go
index 8dcb7b5..8d4e121 100644
--- a/internal/postgres/path_test.go
+++ b/internal/postgres/path_test.go
@@ -188,6 +188,7 @@
 			}
 			opts := []cmp.Option{
 				cmpopts.IgnoreFields(licenses.Metadata{}, "Coverage"),
+				cmpopts.IgnoreFields(internal.UnitMeta{}, "HasGoMod"),
 				cmp.AllowUnexported(source.Info{}, safehtml.HTML{}),
 			}
 			if diff := cmp.Diff(test.want, got, opts...); diff != "" {
@@ -380,6 +381,7 @@
 				}
 				opts := []cmp.Option{
 					cmpopts.IgnoreFields(licenses.Metadata{}, "Coverage"),
+					cmpopts.IgnoreFields(internal.UnitMeta{}, "HasGoMod"),
 					cmp.AllowUnexported(source.Info{}, safehtml.HTML{}),
 				}
 				if diff := cmp.Diff(test.want, got, opts...); diff != "" {
diff --git a/internal/postgres/unit.go b/internal/postgres/unit.go
index 8a2fec9..18e64c9 100644
--- a/internal/postgres/unit.go
+++ b/internal/postgres/unit.go
@@ -37,6 +37,7 @@
 		"m.version",
 		"m.commit_time",
 		"m.source_info",
+		"m.has_go_mod",
 		"u.name",
 		"u.redistributable",
 		"u.license_types",
@@ -67,6 +68,7 @@
 		&um.Version,
 		&um.CommitTime,
 		jsonbScanner{&um.SourceInfo},
+		&um.HasGoMod,
 		&um.Name,
 		&um.IsRedistributable,
 		pq.Array(&licenseTypes),
diff --git a/internal/unit.go b/internal/unit.go
index e766aef..82a116f 100644
--- a/internal/unit.go
+++ b/internal/unit.go
@@ -26,6 +26,7 @@
 	ModulePath string
 	CommitTime time.Time
 	SourceInfo *source.Info
+	HasGoMod   bool
 }
 
 // IsPackage reports whether the path represents a package path.
diff --git a/internal/worker/fetch_test.go b/internal/worker/fetch_test.go
index a20d3ce..622f85e 100644
--- a/internal/worker/fetch_test.go
+++ b/internal/worker/fetch_test.go
@@ -145,6 +145,7 @@
 	myModuleV100 := &internal.Unit{
 		UnitMeta: internal.UnitMeta{
 			ModulePath:        "github.com/my/module",
+			HasGoMod:          true,
 			Version:           sample.VersionString,
 			CommitTime:        testProxyCommitTime,
 			SourceInfo:        source.NewGitHubInfo("https://github.com/my/module", "", sample.VersionString),
@@ -198,6 +199,7 @@
 				UnitMeta: internal.UnitMeta{
 					ModulePath:        "nonredistributable.mod/module",
 					Version:           "v1.0.0",
+					HasGoMod:          true,
 					CommitTime:        testProxyCommitTime,
 					SourceInfo:        nil,
 					IsRedistributable: true,
@@ -224,6 +226,7 @@
 				UnitMeta: internal.UnitMeta{
 					ModulePath:        "nonredistributable.mod/module",
 					Version:           sample.VersionString,
+					HasGoMod:          true,
 					CommitTime:        testProxyCommitTime,
 					SourceInfo:        nil,
 					IsRedistributable: false,
@@ -244,6 +247,7 @@
 				UnitMeta: internal.UnitMeta{
 					ModulePath:        "std",
 					Version:           "v1.12.5",
+					HasGoMod:          true,
 					CommitTime:        stdlib.TestCommitTime,
 					SourceInfo:        source.NewGitHubInfo(goRepositoryURLPrefix+"/go", "src", "go1.12.5"),
 					IsRedistributable: true,
@@ -272,6 +276,7 @@
 				UnitMeta: internal.UnitMeta{
 					ModulePath:        "std",
 					Version:           "v1.12.5",
+					HasGoMod:          true,
 					CommitTime:        stdlib.TestCommitTime,
 					SourceInfo:        source.NewGitHubInfo(goRepositoryURLPrefix+"/go", "src", "go1.12.5"),
 					IsRedistributable: true,
@@ -299,6 +304,7 @@
 				UnitMeta: internal.UnitMeta{
 					ModulePath:        "std",
 					Version:           "v1.12.5",
+					HasGoMod:          true,
 					CommitTime:        stdlib.TestCommitTime,
 					SourceInfo:        source.NewGitHubInfo(goRepositoryURLPrefix+"/go", "src", "go1.12.5"),
 					IsRedistributable: true,
@@ -340,6 +346,7 @@
 				UnitMeta: internal.UnitMeta{
 					ModulePath:        buildConstraintsMod.ModulePath,
 					Version:           buildConstraintsMod.Version,
+					HasGoMod:          false,
 					CommitTime:        testProxyCommitTime,
 					IsRedistributable: true,
 					Path:              buildConstraintsMod.ModulePath + "/cpu",
diff --git a/internal/worker/refetch_test.go b/internal/worker/refetch_test.go
index 2135bd5..a845b48 100644
--- a/internal/worker/refetch_test.go
+++ b/internal/worker/refetch_test.go
@@ -119,7 +119,8 @@
 	}
 	if diff := cmp.Diff(want.UnitMeta, *got,
 		cmp.AllowUnexported(source.Info{}),
-		cmpopts.IgnoreFields(licenses.Metadata{}, "Coverage")); diff != "" {
+		cmpopts.IgnoreFields(licenses.Metadata{}, "Coverage"),
+		cmpopts.IgnoreFields(internal.UnitMeta{}, "HasGoMod"),); diff != "" {
 		t.Fatalf("testDB.GetUnitMeta(ctx, %q, %q) mismatch (-want +got):\n%s", want.ModulePath, want.Version, diff)
 	}
 
@@ -130,7 +131,8 @@
 	if diff := cmp.Diff(want, gotPkg,
 		cmp.AllowUnexported(source.Info{}),
 		cmpopts.IgnoreFields(internal.Unit{}, "Documentation"),
-		cmpopts.IgnoreFields(licenses.Metadata{}, "Coverage")); diff != "" {
+		cmpopts.IgnoreFields(licenses.Metadata{}, "Coverage"),
+		cmpopts.IgnoreFields(internal.UnitMeta{}, "HasGoMod")); diff != "" {
 		t.Errorf("mismatch on readme (-want +got):\n%s", diff)
 	}
 	if got, want := gotPkg.Documentation, want.Documentation; got == nil || want == nil {