diff --git a/src/GF/Devel/Judgements.hs b/src/GF/Devel/Grammar/Judgements.hs
similarity index 86%
rename from src/GF/Devel/Judgements.hs
rename to src/GF/Devel/Grammar/Judgements.hs
index 7be565bf0..b09576e50 100644
--- a/src/GF/Devel/Judgements.hs
+++ b/src/GF/Devel/Grammar/Judgements.hs
@@ -1,6 +1,6 @@
-module GF.Devel.Judgements where
+module GF.Devel.Grammar.Judgements where
 
-import GF.Devel.Terms
+import GF.Devel.Grammar.Terms
 import GF.Infra.Ident
 
 data Judgement = Judgement {
diff --git a/src/GF/Devel/Lookup.hs b/src/GF/Devel/Grammar/Lookup.hs
similarity index 92%
rename from src/GF/Devel/Lookup.hs
rename to src/GF/Devel/Grammar/Lookup.hs
index 741c65472..9236f0222 100644
--- a/src/GF/Devel/Lookup.hs
+++ b/src/GF/Devel/Grammar/Lookup.hs
@@ -1,9 +1,9 @@
-module GF.Devel.Lookup where
+module GF.Devel.Grammar.Lookup where
 
-import GF.Devel.Modules
-import GF.Devel.Judgements
-import GF.Devel.Macros
-import GF.Devel.Terms
+import GF.Devel.Grammar.Modules
+import GF.Devel.Grammar.Judgements
+import GF.Devel.Grammar.Macros
+import GF.Devel.Grammar.Terms
 import GF.Infra.Ident
 
 import GF.Data.Operations
diff --git a/src/GF/Devel/Macros.hs b/src/GF/Devel/Grammar/Macros.hs
similarity index 97%
rename from src/GF/Devel/Macros.hs
rename to src/GF/Devel/Grammar/Macros.hs
index afaf71c52..4848a5e1a 100644
--- a/src/GF/Devel/Macros.hs
+++ b/src/GF/Devel/Grammar/Macros.hs
@@ -1,8 +1,8 @@
-module GF.Devel.Macros where
+module GF.Devel.Grammar.Macros where
 
-import GF.Devel.Terms
-import GF.Devel.Judgements
-import GF.Devel.Modules
+import GF.Devel.Grammar.Terms
+import GF.Devel.Grammar.Judgements
+import GF.Devel.Grammar.Modules
 import GF.Infra.Ident
 
 import GF.Data.Operations
diff --git a/src/GF/Devel/MkJudgements.hs b/src/GF/Devel/Grammar/MkJudgements.hs
similarity index 94%
rename from src/GF/Devel/MkJudgements.hs
rename to src/GF/Devel/Grammar/MkJudgements.hs
index dbe57b0f1..795bf6f67 100644
--- a/src/GF/Devel/MkJudgements.hs
+++ b/src/GF/Devel/Grammar/MkJudgements.hs
@@ -1,8 +1,8 @@
-module GF.Devel.MkJudgements where
+module GF.Devel.Grammar.MkJudgements where
 
-import GF.Devel.Macros
-import GF.Devel.Judgements
-import GF.Devel.Terms
+import GF.Devel.Grammar.Macros
+import GF.Devel.Grammar.Judgements
+import GF.Devel.Grammar.Terms
 import GF.Infra.Ident
 
 import GF.Data.Operations
diff --git a/src/GF/Devel/Modules.hs b/src/GF/Devel/Grammar/Modules.hs
similarity index 91%
rename from src/GF/Devel/Modules.hs
rename to src/GF/Devel/Grammar/Modules.hs
index 112cca221..774cc6387 100644
--- a/src/GF/Devel/Modules.hs
+++ b/src/GF/Devel/Grammar/Modules.hs
@@ -1,7 +1,7 @@
-module GF.Devel.Modules where
+module GF.Devel.Grammar.Modules where
 
-import GF.Devel.Judgements
-import GF.Devel.Terms
+import GF.Devel.Grammar.Judgements
+import GF.Devel.Grammar.Terms
 import GF.Infra.Ident
 
 import GF.Data.Operations
diff --git a/src/GF/Devel/Grammar/SourceToGF.hs b/src/GF/Devel/Grammar/SourceToGF.hs
index 496202e80..d40026851 100644
--- a/src/GF/Devel/Grammar/SourceToGF.hs
+++ b/src/GF/Devel/Grammar/SourceToGF.hs
@@ -21,12 +21,12 @@ module GF.Devel.Grammar.SourceToGF (
   newReservedWords
   ) where
 
-import qualified GF.Devel.Terms as G
+import qualified GF.Devel.Grammar.Terms as G
 ----import qualified GF.Grammar.PrGrammar as GP
-import GF.Devel.Judgements
-import GF.Devel.MkJudgements
-import GF.Devel.Modules
-import qualified GF.Devel.Macros as M
+import GF.Devel.Grammar.Judgements
+import GF.Devel.Grammar.MkJudgements
+import GF.Devel.Grammar.Modules
+import qualified GF.Devel.Grammar.Macros as M
 ----import qualified GF.Compile.Update as U
 --import qualified GF.Infra.Option as GO
 --import qualified GF.Compile.ModDeps as GD
diff --git a/src/GF/Devel/Terms.hs b/src/GF/Devel/Grammar/Terms.hs
similarity index 98%
rename from src/GF/Devel/Terms.hs
rename to src/GF/Devel/Grammar/Terms.hs
index c2a6022c7..bfbdff7d0 100644
--- a/src/GF/Devel/Terms.hs
+++ b/src/GF/Devel/Grammar/Terms.hs
@@ -1,7 +1,6 @@
-module GF.Devel.Terms where
+module GF.Devel.Grammar.Terms where
 
 import GF.Infra.Ident
-import GF.Infra.Modules
 
 import GF.Data.Operations