Limit local Bazel test concurrency

.bazelrc

@@ -77,6 +77,12 @@ common:buildbuddy-openai-rbe --remote_executor=grpcs://openai.buildbuddy.io
 # memory in exchange for higher download concurrency.
 common --jobs=30
 
+# Full local test runs include heavily sharded suites whose processes can
+# contend for CPU and SQLite resources. Keep these limits opt-in so remote and
+# CI configurations retain their existing concurrency.
+test:local-test --jobs=8
+test:local-test --local_test_jobs=2
+
 # Shared remote execution policy. The endpoint-bearing `buildbuddy-*-rbe`
 # configurations include this group; CI configs override TestRunner below
 # when tests must remain local on their runner.

codex-rs/docs/bazel.md

@@ -29,6 +29,16 @@ just bazel-test
 just bazel-clippy
 ```
 
+`just bazel-test` selects the opt-in `local-test` Bazel configuration. It caps
+local build actions at 8 and local test processes at 2 so the heavily sharded
+app-server, core, and TUI suites do not overwhelm developer machines or
+contend excessively for SQLite resources. The cap only controls scheduling:
+all test targets and their configured shards still run.
+
+Direct `bazel test` commands do not select this configuration automatically.
+Use `--config=local-test` for the same scheduling limits. CI uses its existing
+CI-specific configurations and concurrency.
+
 Ordinary local `bazel` and `just` invocations run locally. BuildBuddy cache,
 build event upload, downloads, and remote execution are opt-in configurations.
 

justfile

@@ -121,7 +121,7 @@ bazel-lock-check:
     bazel mod deps --lockfile_mode=error; if ($LASTEXITCODE -ne 0) { Write-Error "MODULE.bazel.lock is out of date. Run 'just bazel-lock-update' and commit the updated lockfile."; exit 1 }
 
 bazel-test:
-    bazel test --test_tag_filters=-argument-comment-lint //... --keep_going
+    bazel test --config=local-test --test_tag_filters=-argument-comment-lint //... --keep_going
 
 [no-cd]
 [unix]