diff --git a/Shogi.UI/Pages/Home/Api/ShogiApi.cs b/Shogi.UI/Pages/Home/Api/ShogiApi.cs
index a1a39e7..2e7b2eb 100644
--- a/Shogi.UI/Pages/Home/Api/ShogiApi.cs
+++ b/Shogi.UI/Pages/Home/Api/ShogiApi.cs
@@ -16,13 +16,16 @@ namespace Shogi.UI.Pages.Home.Api
         private readonly AccountState accountState;
         private readonly HttpClient guestHttpClient;
         private readonly HttpClient msalHttpClient;
+        private readonly string baseUrl;
 
-        public ShogiApi(IHttpClientFactory clientFactory, AccountState accountState)
+        public ShogiApi(IHttpClientFactory clientFactory, AccountState accountState, IConfiguration configuration)
         {
             this.serializerOptions = new JsonSerializerOptions(JsonSerializerDefaults.Web);
             this.accountState = accountState;
             this.guestHttpClient = clientFactory.CreateClient(GuestClientName);
             this.msalHttpClient = clientFactory.CreateClient(MsalClientName);
+            this.baseUrl = configuration["ShogiApiUrl"] ?? throw new InvalidOperationException("Configuration missing.");
+            this.baseUrl = this.baseUrl.TrimEnd('/');
         }
 
         private HttpClient HttpClient => accountState.User?.WhichAccountPlatform switch
@@ -40,7 +43,7 @@ namespace Shogi.UI.Pages.Home.Api
 
         public async Task<Session?> GetSession(string name)
         {
-            var response = await HttpClient.GetAsync(new Uri($"Sessions/{name}", UriKind.Relative));
+            var response = await HttpClient.GetAsync(RelativeUri($"Sessions/{name}"));
             if (response.IsSuccessStatusCode)
             {
                 return (await response.Content.ReadFromJsonAsync<ReadSessionResponse>(serializerOptions))?.Session;
@@ -98,6 +101,6 @@ namespace Shogi.UI.Pages.Home.Api
             return HttpClient.PatchAsync(RelativeUri($"Sessions/{name}/Join"), null);
         }
 
-        private static Uri RelativeUri(string path) => new(path, UriKind.Relative);
+        private Uri RelativeUri(string path) => new($"{this.baseUrl}/{path}", UriKind.Absolute);
     }
 }