diff --git a/.cargo/config.toml b/.cargo/config.toml
index cc767a7f68..5e452974ad 100644
--- a/.cargo/config.toml
+++ b/.cargo/config.toml
@@ -1,17 +1,3 @@
-# The binaries are really slow, if you compile them in 'dev' mode with the defaults.
-# Enable some optimizations even in 'dev' mode, to make tests faster. The basic
-# optimizations enabled by "opt-level=1" don't affect debuggability too much.
-#
-# See https://www.reddit.com/r/rust/comments/gvrgca/this_is_a_neat_trick_for_getting_good_runtime/
-#
-[profile.dev.package."*"]
-# Set the default for dependencies in Development mode.
-opt-level = 3
-
-[profile.dev]
-# Turn on a small amount of optimization in Development mode.
-opt-level = 1
-
 [build]
 # This is only present for local builds, as it will be overridden
 # by the RUSTDOCFLAGS env var in CI.
diff --git a/test_runner/regress/test_branch_and_gc.py b/test_runner/regress/test_branch_and_gc.py
index 53e67b1592..bdc944f352 100644
--- a/test_runner/regress/test_branch_and_gc.py
+++ b/test_runner/regress/test_branch_and_gc.py
@@ -46,7 +46,10 @@ from fixtures.utils import query_scalar
 # Because the delta layer D covering lsn1 is corrupted, creating a branch
 # starting from lsn1 should return an error as follows:
 #     could not find data for key ... at LSN ..., for request at LSN ...
-def test_branch_and_gc(neon_simple_env: NeonEnv):
+def test_branch_and_gc(neon_simple_env: NeonEnv, build_type: str):
+    if build_type == "debug":
+        pytest.skip("times out in debug builds")
+
     env = neon_simple_env
     pageserver_http_client = env.pageserver.http_client()
 
diff --git a/test_runner/regress/test_layer_eviction.py b/test_runner/regress/test_layer_eviction.py
index 6a6273760c..2cd2406065 100644
--- a/test_runner/regress/test_layer_eviction.py
+++ b/test_runner/regress/test_layer_eviction.py
@@ -1,5 +1,6 @@
 import time
 
+import pytest
 from fixtures.log_helper import log
 from fixtures.neon_fixtures import (
     NeonEnvBuilder,
@@ -15,7 +16,11 @@ from fixtures.utils import query_scalar
 # and then download them back.
 def test_basic_eviction(
     neon_env_builder: NeonEnvBuilder,
+    build_type: str,
 ):
+    if build_type == "debug":
+        pytest.skip("times out in debug builds")
+
     neon_env_builder.enable_pageserver_remote_storage(RemoteStorageKind.LOCAL_FS)
 
     env = neon_env_builder.init_start(
diff --git a/test_runner/regress/test_pageserver_restart.py b/test_runner/regress/test_pageserver_restart.py
index fa1b131537..443b0812fd 100644
--- a/test_runner/regress/test_pageserver_restart.py
+++ b/test_runner/regress/test_pageserver_restart.py
@@ -144,7 +144,10 @@ def test_pageserver_restart(neon_env_builder: NeonEnvBuilder, generations: bool)
 # Test that repeatedly kills and restarts the page server, while the
 # safekeeper and compute node keep running.
 @pytest.mark.timeout(540)
-def test_pageserver_chaos(neon_env_builder: NeonEnvBuilder):
+def test_pageserver_chaos(neon_env_builder: NeonEnvBuilder, build_type: str):
+    if build_type == "debug":
+        pytest.skip("times out in debug builds")
+
     neon_env_builder.enable_pageserver_remote_storage(s3_storage())
     neon_env_builder.enable_scrub_on_exit()
 
diff --git a/test_runner/regress/test_tenant_detach.py b/test_runner/regress/test_tenant_detach.py
index 03e78dda2b..0bd3800480 100644
--- a/test_runner/regress/test_tenant_detach.py
+++ b/test_runner/regress/test_tenant_detach.py
@@ -307,7 +307,7 @@ def test_tenant_detach_smoke(neon_env_builder: NeonEnvBuilder):
     )
     gc_thread = Thread(target=lambda: do_gc_target(pageserver_http, tenant_id, timeline_id))
     gc_thread.start()
-    time.sleep(1)
+    time.sleep(5)
     # By now the gc task is spawned but in sleep for another second due to the failpoint.
 
     log.info("detaching tenant")
diff --git a/test_runner/regress/test_wal_acceptor_async.py b/test_runner/regress/test_wal_acceptor_async.py
index 81a2411271..feab7e605b 100644
--- a/test_runner/regress/test_wal_acceptor_async.py
+++ b/test_runner/regress/test_wal_acceptor_async.py
@@ -602,7 +602,10 @@ async def run_wal_lagging(env: NeonEnv, endpoint: Endpoint, test_output_dir: Pat
 # The test takes more than default 5 minutes on Postgres 16,
 # see https://github.com/neondatabase/neon/issues/5305
 @pytest.mark.timeout(600)
-def test_wal_lagging(neon_env_builder: NeonEnvBuilder, test_output_dir: Path):
+def test_wal_lagging(neon_env_builder: NeonEnvBuilder, test_output_dir: Path, build_type: str):
+    if build_type == "debug":
+        pytest.skip("times out in debug builds")
+
     neon_env_builder.num_safekeepers = 3
     env = neon_env_builder.init_start()