diff --git a/packages/squiggle-lang/__tests__/Distributions/Invariants/Means_test.res b/packages/squiggle-lang/__tests__/Distributions/Invariants/Means_test.res
index 01f52b7c..a499565b 100644
--- a/packages/squiggle-lang/__tests__/Distributions/Invariants/Means_test.res
+++ b/packages/squiggle-lang/__tests__/Distributions/Invariants/Means_test.res
@@ -16,7 +16,7 @@ module Internals = {
   let epsilon = 1e3
 
   let mean = GenericDist_Types.Constructors.UsingDists.mean
-  
+
   let expectImpossiblePath: string => assertion = algebraicOp =>
     `${algebraicOp} has`->expect->toEqual("failed")
 
@@ -37,25 +37,24 @@ module Internals = {
   }
 
   let testOperationMean = (
-      distOp: (DistributionTypes.genericDist, DistributionTypes.genericDist) => result<DistributionTypes.genericDist, DistributionTypes.error>, 
-      description: string, 
-      floatOp: (float, float) => float, 
-      dist1': SymbolicDistTypes.symbolicDist, 
-      dist2': SymbolicDistTypes.symbolicDist, 
-      ~epsilon: float
-    ) => {
-    let dist1 = dist1'->DistributionTypes.Symbolic  // ->DistributionTypes.Other
-    let dist2 = dist2'->DistributionTypes.Symbolic  // ->DistributionTypes.Other
+    distOp: (
+      DistributionTypes.genericDist,
+      DistributionTypes.genericDist,
+    ) => result<DistributionTypes.genericDist, DistributionTypes.error>,
+    description: string,
+    floatOp: (float, float) => float,
+    dist1': SymbolicDistTypes.symbolicDist,
+    dist2': SymbolicDistTypes.symbolicDist,
+    ~epsilon: float,
+  ) => {
+    let dist1 = dist1'->DistributionTypes.Symbolic // ->DistributionTypes.Other
+    let dist2 = dist2'->DistributionTypes.Symbolic // ->DistributionTypes.Other
     let received =
-      distOp(dist1, dist2)
-      ->E.R2.fmap(mean)
-      ->E.R2.fmap(run)
-      ->E.R2.fmap(toFloat)
-      ->E.R.toExn
+      distOp(dist1, dist2)->E.R2.fmap(mean)->E.R2.fmap(run)->E.R2.fmap(toFloat)->E.R.toExn
     let expected = floatOp(runMean(dist1), runMean(dist2))
     switch received {
     | None => expectImpossiblePath(description)
-    | Some(x) => expectErrorToBeBounded(x, expected, ~epsilon=epsilon)
+    | Some(x) => expectErrorToBeBounded(x, expected, ~epsilon)
     }
   }
 }
@@ -79,58 +78,67 @@ let algebraicPower = algebraicPower(~env)
 let {testOperationMean, distributions, pairsOfDifferentDistributions, epsilon} = module(Internals)
 
 describe("Means invariant", () => {
-
   describe("for addition", () => {
-    let testAdditionMean = testOperationMean(algebraicAdd, "algebraicAdd", \"+.", ~epsilon=epsilon)  
-    
+    let testAdditionMean = testOperationMean(algebraicAdd, "algebraicAdd", \"+.", ~epsilon)
+
     testAll("of two of the same distribution", distributions, dist => {
-      E.R.liftM2(testAdditionMean, dist, dist) -> E.R.toExn
+      E.R.liftM2(testAdditionMean, dist, dist)->E.R.toExn
     })
 
     testAll("of two different distributions", pairsOfDifferentDistributions, dists => {
       let (dist1, dist2) = dists
-      E.R.liftM2(testAdditionMean, dist1, dist2) -> E.R.toExn
+      E.R.liftM2(testAdditionMean, dist1, dist2)->E.R.toExn
     })
 
     testAll("of two difference distributions", pairsOfDifferentDistributions, dists => {
       let (dist1, dist2) = dists
-      E.R.liftM2(testAdditionMean, dist2, dist1) -> E.R.toExn
+      E.R.liftM2(testAdditionMean, dist2, dist1)->E.R.toExn
     })
   })
 
   describe("for subtraction", () => {
-    let testSubtractionMean = testOperationMean(algebraicSubtract, "algebraicSubtract", \"-.", ~epsilon=epsilon)
+    let testSubtractionMean = testOperationMean(
+      algebraicSubtract,
+      "algebraicSubtract",
+      \"-.",
+      ~epsilon,
+    )
 
     testAll("of two of the same distribution", distributions, dist => {
-      E.R.liftM2(testSubtractionMean, dist, dist) -> E.R.toExn
+      E.R.liftM2(testSubtractionMean, dist, dist)->E.R.toExn
     })
 
     testAll("of two different distributions", pairsOfDifferentDistributions, dists => {
       let (dist1, dist2) = dists
-      E.R.liftM2(testSubtractionMean, dist1, dist2) -> E.R.toExn
+      E.R.liftM2(testSubtractionMean, dist1, dist2)->E.R.toExn
     })
 
     testAll("of two different distributions", pairsOfDifferentDistributions, dists => {
       let (dist1, dist2) = dists
-      E.R.liftM2(testSubtractionMean, dist2, dist1) -> E.R.toExn
+      E.R.liftM2(testSubtractionMean, dist2, dist1)->E.R.toExn
     })
   })
 
   describe("for multiplication", () => {
-    let testMultiplicationMean = testOperationMean(algebraicMultiply, "algebraicMultiply", \"*.", ~epsilon=epsilon)
+    let testMultiplicationMean = testOperationMean(
+      algebraicMultiply,
+      "algebraicMultiply",
+      \"*.",
+      ~epsilon,
+    )
 
     testAll("of two of the same distribution", distributions, dist => {
-      E.R.liftM2(testMultiplicationMean, dist, dist) -> E.R.toExn
+      E.R.liftM2(testMultiplicationMean, dist, dist)->E.R.toExn
     })
 
     testAll("of two different distributions", pairsOfDifferentDistributions, dists => {
       let (dist1, dist2) = dists
-      E.R.liftM2(testMultiplicationMean, dist1, dist2) -> E.R.toExn
+      E.R.liftM2(testMultiplicationMean, dist1, dist2)->E.R.toExn
     })
 
     testAll("of two different distributions", pairsOfDifferentDistributions, dists => {
       let (dist1, dist2) = dists
-      E.R.liftM2(testMultiplicationMean, dist2, dist1) -> E.R.toExn
+      E.R.liftM2(testMultiplicationMean, dist2, dist1)->E.R.toExn
     })
   })
 })
diff --git a/packages/squiggle-lang/__tests__/TestHelpers.res b/packages/squiggle-lang/__tests__/TestHelpers.res
index bff21805..29795fcf 100644
--- a/packages/squiggle-lang/__tests__/TestHelpers.res
+++ b/packages/squiggle-lang/__tests__/TestHelpers.res
@@ -8,7 +8,7 @@ let expectErrorToBeBounded = (received, expected, ~epsilon) => {
   } else {
     distance /. Js.Math.abs_float(expected)
   }
-  error -> expect -> toBeLessThan(epsilon)
+  error->expect->toBeLessThan(epsilon)
 }
 
 let makeTest = (~only=false, str, item1, item2) =>
diff --git a/packages/squiggle-lang/src/rescript/ReducerInterface/ReducerInterface_GenericDistribution.res b/packages/squiggle-lang/src/rescript/ReducerInterface/ReducerInterface_GenericDistribution.res
index 918c4b70..b0ce84e3 100644
--- a/packages/squiggle-lang/src/rescript/ReducerInterface/ReducerInterface_GenericDistribution.res
+++ b/packages/squiggle-lang/src/rescript/ReducerInterface/ReducerInterface_GenericDistribution.res
@@ -117,7 +117,8 @@ module Helpers = {
         | Error(err) => GenDistError(ArgumentError(err))
         }
       }
-    | Some(EvDistribution(b)) => switch parseDistributionArray(args) {
+    | Some(EvDistribution(b)) =>
+      switch parseDistributionArray(args) {
       | Ok(distributions) => mixtureWithDefaultWeights(distributions)
       | Error(err) => GenDistError(ArgumentError(err))
       }
diff --git a/packages/squiggle-lang/src/rescript/Utility/E.res b/packages/squiggle-lang/src/rescript/Utility/E.res
index cb921c39..24e7947c 100644
--- a/packages/squiggle-lang/src/rescript/Utility/E.res
+++ b/packages/squiggle-lang/src/rescript/Utility/E.res
@@ -215,8 +215,8 @@ module R2 = {
     | Ok(r) => Ok(r)
     | Error(e) => map(e)
     }
-  
-  let fmap2 = (xR, f) => 
+
+  let fmap2 = (xR, f) =>
     switch xR {
     | Ok(x) => x->Ok
     | Error(x) => x->f->Error