diff --git a/codex-rs/.config/nextest.toml b/codex-rs/.config/nextest.toml
index 86d00e4637..b2eb62cc9f 100644
--- a/codex-rs/.config/nextest.toml
+++ b/codex-rs/.config/nextest.toml
@@ -11,6 +11,12 @@ max-threads = 1
 [test-groups.core_apply_patch_cli_integration]
 max-threads = 1
 
+[test-groups.core_cli_stream_integration]
+max-threads = 1
+
+[test-groups.codex_exec_integration]
+max-threads = 1
+
 [test-groups.windows_sandbox_legacy_sessions]
 max-threads = 1
 
@@ -39,6 +45,19 @@ test-group = 'app_server_integration'
 filter = 'package(codex-core) & kind(test) & test(apply_patch_cli)'
 test-group = 'core_apply_patch_cli_integration'
 
+[[profile.default.overrides]]
+# These tests spawn Codex CLI subprocesses, so serialize them to avoid Windows
+# process-startup stalls under the full workspace test run.
+filter = 'package(codex-core) & kind(test) & test(cli_stream)'
+test-group = 'core_cli_stream_integration'
+slow-timeout = { period = "30s", terminate-after = 2 }
+
+[[profile.default.overrides]]
+# These tests spawn codex-exec subprocesses and can exceed the default timeout
+# when several resume scenarios start simultaneously on Windows CI.
+filter = 'package(codex-exec) & kind(test)'
+test-group = 'codex_exec_integration'
+
 [[profile.default.overrides]]
 # These tests create restricted-token Windows child processes and private desktops.
 # Serialize them to avoid exhausting Windows session/global desktop resources in CI.
diff --git a/codex-rs/core/tests/suite/cli_stream.rs b/codex-rs/core/tests/suite/cli_stream.rs
index 51d50333c2..6eeedb77ed 100644
--- a/codex-rs/core/tests/suite/cli_stream.rs
+++ b/codex-rs/core/tests/suite/cli_stream.rs
@@ -42,7 +42,7 @@ async fn responses_mode_stream_cli() {
     );
     let bin = codex_utils_cargo_bin::cargo_bin("codex").unwrap();
     let mut cmd = AssertCommand::new(bin);
-    cmd.timeout(Duration::from_secs(30));
+    cmd.timeout(Duration::from_secs(60));
     cmd.arg("exec")
         .arg("--skip-git-repo-check")
         .arg("-c")
@@ -106,7 +106,7 @@ async fn responses_mode_stream_cli_supports_openai_base_url_config_override() {
     let home = TempDir::new().unwrap();
     let bin = codex_utils_cargo_bin::cargo_bin("codex").unwrap();
     let mut cmd = AssertCommand::new(bin);
-    cmd.timeout(Duration::from_secs(30));
+    cmd.timeout(Duration::from_secs(60));
     cmd.arg("exec")
         .arg("--skip-git-repo-check")
         .arg("-c")