diff --git a/machines/agate/default.nix b/machines/agate/default.nix
index abe5dfa..1f6dbff 100644
--- a/machines/agate/default.nix
+++ b/machines/agate/default.nix
@@ -1,4 +1,60 @@
 { lib, ... }:
+let
+  fix-folly-build = (
+    final: prev: {
+      folly =
+        let
+          lib = prev.lib;
+          stdenv = prev.stdenv;
+        in
+        prev.folly.overrideAttrs {
+          checkPhase = ''
+            runHook preCheck
+
+            ctest -j $NIX_BUILD_CORES --output-on-failure --exclude-regex ${
+              lib.escapeShellArg (
+                lib.concatMapStringsSep "|" (test: "^${lib.escapeRegex test}$") (
+                  [
+                    "concurrency_concurrent_hash_map_test.*/ConcurrentHashMapTest/*.StressTestReclamation"
+                    "io_async_ssl_session_test.SSLSessionTest.BasicTest"
+                    "io_async_ssl_session_test.SSLSessionTest.NullSessionResumptionTest"
+                    "singleton_thread_local_test.SingletonThreadLocalDeathTest.Overload"
+
+                    # very strict timing constraints, will fail under load
+                    "io_async_hh_wheel_timer_test.HHWheelTimerTest.CancelTimeout"
+                    "io_async_hh_wheel_timer_test.HHWheelTimerTest.DefaultTimeout"
+                    "io_async_hh_wheel_timer_test.HHWheelTimerTest.DeleteWheelInTimeout"
+                    "io_async_hh_wheel_timer_test.HHWheelTimerTest.DestroyTimeoutSet"
+                    "io_async_hh_wheel_timer_test.HHWheelTimerTest.FireOnce"
+                    "io_async_hh_wheel_timer_test.HHWheelTimerTest.GetTimeRemaining"
+                    "io_async_hh_wheel_timer_test.HHWheelTimerTest.IntrusivePtr"
+                    "io_async_hh_wheel_timer_test.HHWheelTimerTest.Level1"
+                    "io_async_hh_wheel_timer_test.HHWheelTimerTest.NegativeTimeout"
+                    "io_async_hh_wheel_timer_test.HHWheelTimerTest.ReschedTest"
+                    "io_async_hh_wheel_timer_test.HHWheelTimerTest.SlowFast"
+                    "concurrent_skip_list_test.ConcurrentSkipList.ConcurrentAdd"
+                  ]
+                  ++ lib.optionals stdenv.hostPlatform.isLinux [
+                    "concurrency_cache_locality_test.CacheLocality.BenchmarkSysfs"
+                    "concurrency_cache_locality_test.CacheLocality.LinuxActual"
+                    "futures_future_test.Future.NoThrow"
+                    "futures_retrying_test.RetryingTest.largeRetries"
+                  ]
+                  ++ lib.optionals stdenv.hostPlatform.isDarwin [
+                    "buffered_atomic_test.BufferedAtomic.singleThreadUnguardedAccess"
+                    "io_async_notification_queue_test.NotificationQueueTest.UseAfterFork"
+                    "container_heap_vector_types_test.HeapVectorTypes.SimpleSetTes"
+                  ]
+                )
+              )
+            }
+
+            runHook postCheck
+          '';
+        };
+    }
+  );
+in
 {
   imports = [
     ./hardware-configuration.nix
@@ -48,6 +104,7 @@
   };
 
   nixpkgs.config.contentAddressedByDefault = true;
+  nixpkgs.overlays = [ fix-folly-build ];
 
   services.tailscale = {
     enable = true;