diff --git a/appview/db/language.go b/appview/db/language.go
--- a/appview/db/language.go
+++ b/appview/db/language.go
@@ -10,59 +10,6 @@
 	"tangled.org/core/orm"
 )
 
-func GetRepoLanguages(e Execer, filters ...orm.Filter) ([]models.RepoLanguage, error) {
-	var conditions []string
-	var args []any
-	for _, filter := range filters {
-		conditions = append(conditions, filter.Condition())
-		args = append(args, filter.Arg()...)
-	}
-
-	whereClause := ""
-	if conditions != nil {
-		whereClause = " where " + strings.Join(conditions, " and ")
-	}
-
-	query := fmt.Sprintf(
-		`select id, repo_did, ref, is_default_ref, language, bytes from repo_languages %s`,
-		whereClause,
-	)
-	rows, err := e.Query(query, args...)
-	if err != nil {
-		return nil, fmt.Errorf("failed to execute query: %w ", err)
-	}
-	defer rows.Close()
-
-	var langs []models.RepoLanguage
-	for rows.Next() {
-		var rl models.RepoLanguage
-		var isDefaultRef int
-
-		err := rows.Scan(
-			&rl.Id,
-			&rl.RepoDid,
-			&rl.Ref,
-			&isDefaultRef,
-			&rl.Language,
-			&rl.Bytes,
-		)
-		if err != nil {
-			return nil, fmt.Errorf("failed to scan: %w ", err)
-		}
-
-		if isDefaultRef != 0 {
-			rl.IsDefaultRef = true
-		}
-
-		langs = append(langs, rl)
-	}
-	if err = rows.Err(); err != nil {
-		return nil, fmt.Errorf("failed to scan rows: %w ", err)
-	}
-
-	return langs, nil
-}
-
 func InsertRepoLanguages(e Execer, langs []models.RepoLanguage) error {
 	stmt, err := e.Prepare(
 		"insert or replace into repo_languages (repo_did, ref, is_default_ref, language, bytes) values (?, ?, ?, ?, ?)",
diff --git a/appview/repo/index.go b/appview/repo/index.go
--- a/appview/repo/index.go
+++ b/appview/repo/index.go
@@ -114,10 +114,39 @@
 
 	var languageInfo []types.RepoLanguageDetails
 	if !result.IsEmpty {
-		languageInfo, err = rp.getLanguageInfo(r.Context(), syntax.DID(f.RepoDid), result.Ref)
+		langs, err := rp.getLanguageInfo(r.Context(), syntax.DID(f.RepoDid), result.Ref)
 		if err != nil {
 			l.Warn("failed to compute language percentages", "err", err)
 			// non-fatal
+		} else if ref == "" { // when request didn't specified ref, we are fetching default branch.
+			if err := func(repo syntax.DID, ref string, langs []*tangled.GitTempListLanguages_Language) error {
+				tx, err := rp.db.Begin()
+				if err != nil {
+					return err
+				}
+				defer tx.Rollback()
+
+				var mlangs []models.RepoLanguage
+				for _, lang := range langs {
+					mlangs = append(mlangs, models.RepoLanguage{
+						RepoDid:      repo,
+						Ref:          ref,
+						IsDefaultRef: true,
+						Language:     lang.Name,
+						Bytes:        lang.Size,
+					})
+				}
+
+				if err := db.UpdateRepoLanguages(tx, syntax.DID(f.RepoDid), ref, mlangs); err != nil {
+					return err
+				}
+
+				return tx.Commit()
+			}(syntax.DID(f.RepoDid), result.Ref, langs); err != nil {
+				l.Error("failed to populate appview repo languages index", "err", err)
+				// non-fatal
+			}
+			languageInfo = makeLanguageStats(langs)
 		}
 	}
 
@@ -151,41 +180,39 @@
 	ctx context.Context,
 	repoId syntax.DID,
 	ref string,
-) ([]types.RepoLanguageDetails, error) {
-	var langs []models.RepoLanguage
+) ([]*tangled.GitTempListLanguages_Language, error) {
 	// non-fatal, fetch langs from knotmirror via XRPC
 	xrpcc := &indigoxrpc.Client{
 		Host:   rp.config.KnotMirror.Url,
 		Client: http.DefaultClient,
 	}
-	ls, err := tangled.GitTempListLanguages(ctx, xrpcc, ref, repoId.String())
+	out, err := tangled.GitTempListLanguages(ctx, xrpcc, ref, repoId.String())
 	if err != nil {
 		return nil, fmt.Errorf("calling knotmirror git.listLanguages: %w", err)
 	}
 
-	if ls == nil || ls.Languages == nil {
+	if out == nil || out.Languages == nil {
 		return nil, nil
 	}
 
+	return out.Languages, nil
+}
+
+func makeLanguageStats(langs []*tangled.GitTempListLanguages_Language) []types.RepoLanguageDetails {
+	if len(langs) == 0 {
+		return nil
+	}
 	var total int64
-	for _, lang := range ls.Languages {
+	for _, lang := range langs {
 		total += lang.Size
-		langs = append(langs, models.RepoLanguage{
-			RepoDid:  repoId,
-			Ref:      ref,
-			Language: lang.Name,
-			Bytes:    lang.Size,
-		})
 	}
 
 	var languageStats []types.RepoLanguageDetails
 	for _, l := range langs {
-		percentage := float32(l.Bytes) / float32(total) * 100
-		color := enry.GetColor(l.Language)
 		languageStats = append(languageStats, types.RepoLanguageDetails{
-			Name:       l.Language,
-			Percentage: percentage,
-			Color:      color,
+			Name:       l.Name,
+			Color:      enry.GetColor(l.Name),
+			Percentage: float32(l.Size) / float32(total) * 100,
 		})
 	}
 
@@ -201,8 +228,7 @@
 		}
 		return languageStats[i].Name < languageStats[j].Name
 	})
-
-	return languageStats, nil
+	return languageStats
 }
 
 // buildIndexResponse creates a RepoIndexResponse by combining multiple xrpc calls in parallel
diff --git a/appview/repo/opengraph.go b/appview/repo/opengraph.go
--- a/appview/repo/opengraph.go
+++ b/appview/repo/opengraph.go
@@ -22,10 +22,11 @@
 
 	avatarUrl := rp.pages.AvatarUrl(f.Did, "256")
 
-	languageStats, err := rp.getLanguageInfo(r.Context(), syntax.DID(f.RepoDid), "")
+	langs, err := rp.getLanguageInfo(r.Context(), syntax.DID(f.RepoDid), "")
 	if err != nil {
 		log.Printf("failed to get language stats from knotmirror: %v", err)
 	}
+	languageStats := makeLanguageStats(langs)
 
 	ogLanguages := []ogre.LanguageData{}
 	for _, lang := range languageStats {