diff --git a/src/Command.hs b/src/Command.hs
index 23a56c030..d64fe74dd 100644
--- a/src/Command.hs
+++ b/src/Command.hs
@@ -6,6 +6,7 @@ module Command
 import Command.Diff as C
 import Command.Parse as C
 import Control.Monad.Free.Freer
+import Data.Functor.Both
 import Data.List ((\\))
 import Data.RandomWalkSimilarity
 import Data.Record
@@ -22,6 +23,7 @@ import Git.Types
 import GitmonClient
 import Language
 import Prologue
+import Renderer
 import Source
 import Syntax
 import Term
@@ -34,8 +36,9 @@ data CommandF f where
 
   Diff :: Term (Syntax Text) (Record DefaultFields) -> Term (Syntax Text) (Record DefaultFields) -> CommandF (Diff (Syntax Text) (Record DefaultFields))
 
+  RenderDiff :: DiffRenderer fields output -> SourceBlob -> SourceBlob -> Diff (Syntax Text) (Record fields) -> CommandF output
+
   -- render a term
-  -- render a diff
 
   -- parallelize diffs of a list of paths + git shas
   -- explicit gitmon effects/events
@@ -107,3 +110,6 @@ runCommand = iterFreerA $ \ command yield -> case command of
           getLabel (h :< t) = (Info.category h, case t of
             Leaf s -> Just s
             _ -> Nothing)
+
+  RenderDiff renderer blob1 blob2 diff ->
+    yield (runDiffRenderer' renderer (both blob1 blob2) diff)
diff --git a/src/Renderer.hs b/src/Renderer.hs
index 5080b0208..07e76daab 100644
--- a/src/Renderer.hs
+++ b/src/Renderer.hs
@@ -36,8 +36,8 @@ data DiffRenderer fields output where
   SExpressionDiffRenderer :: (HasField fields Category, HasField fields SourceSpan) => SExpressionFormat -> DiffRenderer fields ByteString
   ToCRenderer :: HasDefaultFields fields => DiffRenderer fields (Map Text (Map Text [Value]))
 
-runDiffRenderer :: Both SourceBlob -> Diff (Syntax Text) (Record fields) -> DiffRenderer fields output -> Output
-runDiffRenderer sources diff renderer = case renderer of
+runDiffRenderer :: DiffRenderer fields output -> Both SourceBlob -> Diff (Syntax Text) (Record fields) -> Output
+runDiffRenderer renderer sources diff = case renderer of
   SplitRenderer -> SplitOutput (R.split sources diff)
   PatchRenderer -> PatchOutput (R.patch sources diff)
   JSONDiffRenderer -> JSONOutput (R.json sources diff)
@@ -45,8 +45,8 @@ runDiffRenderer sources diff renderer = case renderer of
   SExpressionDiffRenderer format -> SExpressionOutput (R.sExpression format sources diff)
   ToCRenderer -> TOCOutput (R.toc sources diff)
 
-runDiffRenderer' :: Both SourceBlob -> Diff (Syntax Text) (Record fields) -> DiffRenderer fields output -> output
-runDiffRenderer' sources diff renderer = case renderer of
+runDiffRenderer' :: DiffRenderer fields output -> Both SourceBlob -> Diff (Syntax Text) (Record fields) -> output
+runDiffRenderer' renderer sources diff = case renderer of
   SplitRenderer -> R.split sources diff
   PatchRenderer -> R.patch sources diff
   JSONDiffRenderer -> R.json sources diff