diff --git a/src/Control/Carrier/Accum/FixedStrict.hs b/src/swarm-util/Control/Carrier/Accum/FixedStrict.hs
similarity index 100%
rename from src/Control/Carrier/Accum/FixedStrict.hs
rename to src/swarm-util/Control/Carrier/Accum/FixedStrict.hs
diff --git a/src/Data/BoolExpr/Simplify.hs b/src/swarm-util/Data/BoolExpr/Simplify.hs
similarity index 100%
rename from src/Data/BoolExpr/Simplify.hs
rename to src/swarm-util/Data/BoolExpr/Simplify.hs
diff --git a/src/Swarm/Util.hs b/src/swarm-util/Swarm/Util.hs
similarity index 100%
rename from src/Swarm/Util.hs
rename to src/swarm-util/Swarm/Util.hs
diff --git a/src/Swarm/Util/Erasable.hs b/src/swarm-util/Swarm/Util/Erasable.hs
similarity index 100%
rename from src/Swarm/Util/Erasable.hs
rename to src/swarm-util/Swarm/Util/Erasable.hs
diff --git a/src/Swarm/Util/Lens.hs b/src/swarm-util/Swarm/Util/Lens.hs
similarity index 100%
rename from src/Swarm/Util/Lens.hs
rename to src/swarm-util/Swarm/Util/Lens.hs
diff --git a/src/Swarm/Util/Parse.hs b/src/swarm-util/Swarm/Util/Parse.hs
similarity index 100%
rename from src/Swarm/Util/Parse.hs
rename to src/swarm-util/Swarm/Util/Parse.hs
diff --git a/src/Swarm/Util/RingBuffer.hs b/src/swarm-util/Swarm/Util/RingBuffer.hs
similarity index 100%
rename from src/Swarm/Util/RingBuffer.hs
rename to src/swarm-util/Swarm/Util/RingBuffer.hs
diff --git a/src/Swarm/Util/UnitInterval.hs b/src/swarm-util/Swarm/Util/UnitInterval.hs
similarity index 100%
rename from src/Swarm/Util/UnitInterval.hs
rename to src/swarm-util/Swarm/Util/UnitInterval.hs
diff --git a/src/Swarm/Util/WindowedCounter.hs b/src/swarm-util/Swarm/Util/WindowedCounter.hs
similarity index 100%
rename from src/Swarm/Util/WindowedCounter.hs
rename to src/swarm-util/Swarm/Util/WindowedCounter.hs
diff --git a/src/Swarm/Util/Yaml.hs b/src/swarm-util/Swarm/Util/Yaml.hs
similarity index 100%
rename from src/Swarm/Util/Yaml.hs
rename to src/swarm-util/Swarm/Util/Yaml.hs
diff --git a/swarm.cabal b/swarm.cabal
index 1b40bfa3e..2cb027dbf 100644
--- a/swarm.cabal
+++ b/swarm.cabal
@@ -95,11 +95,51 @@ common ghc2021-extensions
       -- Not GHC2021, but until we get \cases we use \case a lot
       LambdaCase
 
-library
+
+library swarm-util
     import:           stan-config, common, ghc2021-extensions
     exposed-modules:  Control.Carrier.Accum.FixedStrict
                       Data.BoolExpr.Simplify
-                      Swarm.App
+                      Swarm.Util
+                      Swarm.Util.Erasable
+                      Swarm.Util.Lens
+                      Swarm.Util.Parse
+                      Swarm.Util.RingBuffer
+                      Swarm.Util.UnitInterval
+                      Swarm.Util.WindowedCounter
+                      Swarm.Util.Yaml
+    other-modules:    Paths_swarm
+    autogen-modules:  Paths_swarm
+    build-depends:    base                          >= 4.14 && < 4.19,
+                      aeson                         >= 2 && < 2.2,
+                      boolexpr                      >= 0.2 && < 0.3,
+                      clock                         >= 0.8.2 && < 0.9,
+                      containers                    >= 0.6.2 && < 0.7,
+                      directory                     >= 1.3 && < 1.4,
+                      either                        >= 5.0 && < 5.1,
+                      filepath                      >= 1.4 && < 1.5,
+                      fused-effects                 >= 1.1.1.1 && < 1.2,
+                      lens                          >= 4.19 && < 5.3,
+                      minimorph                     >= 0.3 && < 0.4,
+                      mtl                           >= 2.2.2 && < 2.4,
+                      template-haskell              >= 2.16 && < 2.21,
+                      text                          >= 1.2.4 && < 2.1,
+                      vector                        >= 0.12 && < 0.14,
+                      witch                         >= 1.1.1.0 && < 1.3,
+                      yaml                          >= 0.11 && < 0.11.12.0,
+                      transformers                  >= 0.5 && < 0.7,
+                      servant-docs                  >= 0.12 && < 0.14,
+                      megaparsec                    >= 9.6.1 && < 9.7,
+    hs-source-dirs:   src/swarm-util
+    default-language: Haskell2010
+    default-extensions:
+      -- Avoid unexpected unevaluated thunk buildup
+      -- See discussion in #415
+      StrictData
+
+library
+    import:           stan-config, common, ghc2021-extensions
+    exposed-modules:  Swarm.App
                       Swarm.Constant
                       Swarm.Doc.Keyword
                       Swarm.Doc.Pedagogy
@@ -244,17 +284,21 @@ library
                       Swarm.TUI.Model.Structure
                       Swarm.TUI.Model.UI
                       Swarm.TUI.Panel
-                      Swarm.Util
                       Swarm.Util.Effect
-                      Swarm.Util.Erasable
-                      Swarm.Util.Lens
-                      Swarm.Util.Parse
-                      Swarm.Util.RingBuffer
-                      Swarm.Util.UnitInterval
-                      Swarm.Util.WindowedCounter
-                      Swarm.Util.Yaml
                       Swarm.Version
                       Swarm.Web
+
+    reexported-modules: Control.Carrier.Accum.FixedStrict
+                      , Data.BoolExpr.Simplify
+                      , Swarm.Util
+                      , Swarm.Util.Erasable
+                      , Swarm.Util.Lens
+                      , Swarm.Util.Parse
+                      , Swarm.Util.RingBuffer
+                      , Swarm.Util.UnitInterval
+                      , Swarm.Util.WindowedCounter
+                      , Swarm.Util.Yaml
+
     other-modules:    Paths_swarm
     autogen-modules:  Paths_swarm
 
@@ -290,7 +334,6 @@ library
                       linear                        >= 1.21.6 && < 1.23,
                       lsp                           >= 1.6 && < 1.7,
                       megaparsec                    >= 9.6.1 && < 9.7,
-                      minimorph                     >= 0.3 && < 0.4,
                       transformers                  >= 0.5 && < 0.7,
                       mtl                           >= 2.2.2 && < 2.4,
                       murmur3                       >= 1.0.4 && < 1.1,
@@ -328,6 +371,7 @@ library
       build-depends:  vty-windows                   >= 0.1.0.3 && < 0.2
     else
       build-depends:  vty-unix                      >= 0.1.0.0 && < 0.2
+    build-depends:    swarm-util
     hs-source-dirs:   src
     default-language: Haskell2010
     default-extensions: