diff --git a/package.yaml b/package.yaml
index 94eacf487..046ed5946 100644
--- a/package.yaml
+++ b/package.yaml
@@ -254,7 +254,7 @@ ghc-options:
   - -fno-warn-unrecognised-pragmas
   - -fno-warn-partial-type-signatures
   - -fno-max-relevant-binds
-  - -j
+  - -j2
   - -freduction-depth=0
 when:
   - condition: flag(pedantic)
@@ -271,7 +271,7 @@ when:
       cpp-options: -DDEVELOPMENT
     else:
       ghc-options:
-        - -O
+        - -O0
         - -fllvm
         - +RTS -K0 -RTS
 data-files: