diff --git a/backend/internal/core/episode/ports.go b/backend/internal/core/episode/ports.go
new file mode 100644
index 0000000..6a5518b
--- /dev/null
+++ b/backend/internal/core/episode/ports.go
@@ -0,0 +1,12 @@
+package episode
+
+import "context"
+
+// UseCases captures the inbound port for episode-related interactions.
+type UseCases interface {
+	GetCurrent(ctx context.Context) (Episode, error)
+	SetCurrent(ctx context.Context, id int64, start string) (Episode, error)
+	MoveToArchive(ctx context.Context, ids []int64) (MoveResult, error)
+	ListAll(ctx context.Context) ([]Episode, error)
+	Delete(ctx context.Context, id int64) error
+}
diff --git a/backend/internal/http/handlers.go b/backend/internal/http/handlers.go
index 96dfd4b..fa34e73 100644
--- a/backend/internal/http/handlers.go
+++ b/backend/internal/http/handlers.go
@@ -7,12 +7,11 @@ import (
 	"time"
 
 	"watch-party-backend/internal/core/episode"
-	"watch-party-backend/internal/service"
 
 	"github.com/gin-gonic/gin"
 )
 
-func NewRouter(svc service.EpisodeService) *gin.Engine {
+func NewRouter(svc episode.UseCases) *gin.Engine {
 	r := gin.New()
 	r.Use(gin.Logger(), gin.Recovery())
 
@@ -54,7 +53,7 @@ func timeHandler(c *gin.Context) {
 // @Failure      404 {object} HTTPError "no current row found"
 // @Failure      500 {object} HTTPError "query failed"
 // @Router       /api/v1/current [get]
-func getCurrentHandler(svc service.EpisodeService) gin.HandlerFunc {
+func getCurrentHandler(svc episode.UseCases) gin.HandlerFunc {
 	return func(c *gin.Context) {
 		cur, err := svc.GetCurrent(c.Request.Context())
 		if err != nil {
@@ -81,7 +80,7 @@ func getCurrentHandler(svc service.EpisodeService) gin.HandlerFunc {
 // @Failure      404   {object}  HTTPError "id not found"
 // @Failure      500   {object}  HTTPError "update failed"
 // @Router       /api/v1/current [post]
-func setCurrentHandler(svc service.EpisodeService) gin.HandlerFunc {
+func setCurrentHandler(svc episode.UseCases) gin.HandlerFunc {
 	return func(c *gin.Context) {
 		var req SetCurrentReq
 		if err := c.ShouldBindJSON(&req); err != nil {
@@ -117,7 +116,7 @@ func setCurrentHandler(svc service.EpisodeService) gin.HandlerFunc {
 // @Failure      400   {object}  HTTPError "empty ids"
 // @Failure      500   {object}  HTTPError "move failed"
 // @Router       /api/v1/archive [post]
-func moveToArchiveHandler(svc service.EpisodeService) gin.HandlerFunc {
+func moveToArchiveHandler(svc episode.UseCases) gin.HandlerFunc {
 	return func(c *gin.Context) {
 		var req MoveReq
 		if err := c.ShouldBindJSON(&req); err != nil {
@@ -158,7 +157,7 @@ func moveToArchiveHandler(svc service.EpisodeService) gin.HandlerFunc {
 // @Success      200 {array} CurrentResponse
 // @Failure      500 {object} HTTPError "list failed"
 // @Router       /api/v1/shows [get]
-func listShowsHandler(svc service.EpisodeService) gin.HandlerFunc {
+func listShowsHandler(svc episode.UseCases) gin.HandlerFunc {
 	return func(c *gin.Context) {
 		items, err := svc.ListAll(c.Request.Context())
 		if err != nil {
@@ -180,7 +179,7 @@ func listShowsHandler(svc service.EpisodeService) gin.HandlerFunc {
 // @Failure      404 {object}  HTTPError "id not found"
 // @Failure      500 {object}  HTTPError "delete failed"
 // @Router       /api/v1/shows [delete]
-func deleteShowsHandler(svc service.EpisodeService) gin.HandlerFunc {
+func deleteShowsHandler(svc episode.UseCases) gin.HandlerFunc {
 	return func(c *gin.Context) {
 		idStr := c.Query("id")
 		id, err := strconv.ParseInt(idStr, 10, 64)
diff --git a/backend/internal/http/handlers_test.go b/backend/internal/http/handlers_test.go
index 28a6031..6ee5e80 100644
--- a/backend/internal/http/handlers_test.go
+++ b/backend/internal/http/handlers_test.go
@@ -11,12 +11,11 @@ import (
 
 	"watch-party-backend/internal/core/episode"
 	httpapi "watch-party-backend/internal/http"
-	"watch-party-backend/internal/service"
 
 	"github.com/gin-gonic/gin"
 )
 
-// ---- fake service implementing service.EpisodeService ----
+// ---- fake service implementing episode.UseCases ----
 
 type fakeSvc struct {
 	cur       episode.Episode
@@ -55,7 +54,7 @@ func (f *fakeSvc) Delete(ctx context.Context, id int64) error {
 
 // ---- helpers ----
 
-func newRouterWithSvc(svc service.EpisodeService) *gin.Engine {
+func newRouterWithSvc(svc episode.UseCases) *gin.Engine {
 	gin.SetMode(gin.TestMode)
 	return httpapi.NewRouter(svc)
 }
diff --git a/backend/internal/service/episode_service.go b/backend/internal/service/episode_service.go
index 4de7f94..fc160f8 100644
--- a/backend/internal/service/episode_service.go
+++ b/backend/internal/service/episode_service.go
@@ -8,29 +8,22 @@ import (
 	"watch-party-backend/internal/core/episode"
 )
 
-type EpisodeService interface {
-	GetCurrent(ctx context.Context) (episode.Episode, error)
-	SetCurrent(ctx context.Context, id int64, start string) (episode.Episode, error)
-	MoveToArchive(ctx context.Context, ids []int64) (episode.MoveResult, error)
-	ListAll(ctx context.Context) ([]episode.Episode, error)
-	Delete(ctx context.Context, id int64) error
-}
-
-type episodeService struct {
+// Service implements the episode.UseCases port.
+type Service struct {
 	repo episode.Repository
 }
 
-func NewEpisodeService(r episode.Repository) EpisodeService {
-	return &episodeService{repo: r}
+func NewEpisodeService(r episode.Repository) *Service {
+	return &Service{repo: r}
 }
 
-func (s *episodeService) ListAll(ctx context.Context) ([]episode.Episode, error) {
+func (s *Service) ListAll(ctx context.Context) ([]episode.Episode, error) {
 	c, cancel := context.WithTimeout(ctx, 5*time.Second)
 	defer cancel()
 	return s.repo.ListAll(c)
 }
 
-func (s *episodeService) GetCurrent(ctx context.Context) (episode.Episode, error) {
+func (s *Service) GetCurrent(ctx context.Context) (episode.Episode, error) {
 	c, cancel := context.WithTimeout(ctx, 3*time.Second)
 	defer cancel()
 	return s.repo.GetCurrent(c)
@@ -38,7 +31,7 @@ func (s *episodeService) GetCurrent(ctx context.Context) (episode.Episode, error
 
 var hhmmss = regexp.MustCompile(`^(?:[01]\d|2[0-3]):[0-5]\d:[0-5]\d$`)
 
-func (s *episodeService) SetCurrent(ctx context.Context, id int64, start string) (episode.Episode, error) {
+func (s *Service) SetCurrent(ctx context.Context, id int64, start string) (episode.Episode, error) {
 	if !hhmmss.MatchString(start) {
 		return episode.Episode{}, episode.ErrInvalidStartTime
 	}
@@ -50,7 +43,7 @@ func (s *episodeService) SetCurrent(ctx context.Context, id int64, start string)
 	return s.repo.GetCurrent(c)
 }
 
-func (s *episodeService) MoveToArchive(ctx context.Context, ids []int64) (episode.MoveResult, error) {
+func (s *Service) MoveToArchive(ctx context.Context, ids []int64) (episode.MoveResult, error) {
 	uniq := make([]int64, 0, len(ids))
 	seen := make(map[int64]struct{}, len(ids))
 	for _, id := range ids {
@@ -68,7 +61,7 @@ func (s *episodeService) MoveToArchive(ctx context.Context, ids []int64) (episod
 	return s.repo.MoveToArchive(c, uniq)
 }
 
-func (s *episodeService) Delete(ctx context.Context, id int64) error {
+func (s *Service) Delete(ctx context.Context, id int64) error {
 	c, cancel := context.WithTimeout(ctx, 5*time.Second)
 	defer cancel()
 	return s.repo.Delete(c, id)