diff --git a/pkg/relayer/miner/miner.go b/pkg/relayer/miner/miner.go
index 940e6a62c..3537128c5 100644
--- a/pkg/relayer/miner/miner.go
+++ b/pkg/relayer/miner/miner.go
@@ -63,7 +63,9 @@ func (mnr *miner) MinedRelays(
 	ctx context.Context,
 	servedRelaysObs relayer.RelaysObservable,
 ) relayer.MinedRelaysObservable {
-	// TODO_IN_THIS_COMMIT: comment...
+	// NB: must cast back to generic observable type to use with Map.
+	// relayer.RelaysObervable cannot be an alias due to gomock's lack of
+	// support for generic types.
 	relaysObs := observable.Observable[*servicetypes.Relay](servedRelaysObs)
 
 	// Map servedRelaysObs to a new observable of an either type, populated with
diff --git a/pkg/relayer/session/session.go b/pkg/relayer/session/session.go
index d917a7ca1..3316d28c9 100644
--- a/pkg/relayer/session/session.go
+++ b/pkg/relayer/session/session.go
@@ -93,7 +93,9 @@ func NewRelayerSessions(
 // network as necessary.
 // It IS NOT BLOCKING as map operations run in their own goroutines.
 func (rs *relayerSessionsManager) Start(ctx context.Context) {
-	// TODO_IN_THIS_COMMIT: comment...
+	// NB: must cast back to generic observable type to use with Map.
+	// relayer.MinedRelaysObservable cannot be an alias due to gomock's lack of
+	// support for generic types.
 	relayObs := observable.Observable[*relayer.MinedRelay](rs.relayObs)
 
 	// Map eitherMinedRelays to a new observable of an error type which is