diff --git a/CHANGELOG.md b/CHANGELOG.md
index d98239e9bf..b75dfdc6a2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -24,6 +24,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 * `futhark fmt`: do not throw away doc comments for `local`
   definitions.
 
+* `futhark fmt`: improve formatting of value specs.
+
 ## [0.25.25]
 
 ### Added
diff --git a/src/Futhark/Fmt/Printer.hs b/src/Futhark/Fmt/Printer.hs
index 32fc3dfd76..8be7b96495 100644
--- a/src/Futhark/Fmt/Printer.hs
+++ b/src/Futhark/Fmt/Printer.hs
@@ -511,7 +511,7 @@ instance Format UncheckedSpec where
     where
       sub
         | null ps = fmtName bindingStyle name
-        | otherwise = fmtName bindingStyle name <+> align (sep line $ map fmt ps)
+        | otherwise = fmtName bindingStyle name <+> align (sep space $ map fmt ps)
   fmt (ModSpec name mte doc loc) =
     addComments loc $ fmt doc <> "module" <+> fmtName bindingStyle name <> ":" <+> fmt mte
   fmt (IncludeSpec mte loc) = addComments loc $ "include" <+> fmt mte
diff --git a/tests_fmt/expected/modules.fut b/tests_fmt/expected/modules.fut
index 80a090d291..7bc242bf3b 100644
--- a/tests_fmt/expected/modules.fut
+++ b/tests_fmt/expected/modules.fut
@@ -34,6 +34,13 @@ module type mt4 = {
   val g [n] :
     [n]i32
     -> [n]i32
+
+  val block [m1] [m2] [n1] [n2] :
+    (A: [m1][n1]i32)
+    -> (B: [m1][n2]i32)
+    -> (C: [m2][n1]i32)
+    -> (D: [m2][n2]i32)
+    -> [m1 + m2][n1 + n2]i32
 }
 
 module pm1 (P: {}) : {} = {
diff --git a/tests_fmt/modules.fut b/tests_fmt/modules.fut
index dfce8e67cb..b93701b457 100644
--- a/tests_fmt/modules.fut
+++ b/tests_fmt/modules.fut
@@ -30,6 +30,9 @@ module type mt4 = {
  -> [n]i32
 
 
+  val block [m1] [m2] [n1] [n2] :
+    (A: [m1][n1]i32) -> (B: [m1][n2]i32) -> (C: [m2][n1]i32) -> (D: [m2][n2]i32)
+    -> [m1 + m2][n1 + n2]i32
 }
 
 module pm1 (P: {}) : {} = {