diff --git a/tests/functional/lang/eval-fail-assert.err.exp b/tests/functional/lang/eval-fail-assert.err.exp
index 0656ec81c..4bb63c29a 100644
--- a/tests/functional/lang/eval-fail-assert.err.exp
+++ b/tests/functional/lang/eval-fail-assert.err.exp
@@ -1,28 +1,21 @@
 error:
-       … while evaluating the attribute 'body'
-         at /pwd/lang/eval-fail-assert.nix:4:3:
-            3|
-            4|   body = x "x";
-             |   ^
-            5| }
-
        … from call site
-         at /pwd/lang/eval-fail-assert.nix:4:10:
-            3|
-            4|   body = x "x";
-             |          ^
-            5| }
+         at /pwd/lang/eval-fail-assert.nix:4:1:
+            3| in
+            4| x "x"
+             | ^
+            5|
 
        … while calling 'x'
          at /pwd/lang/eval-fail-assert.nix:2:7:
-            1| let {
+            1| let
             2|   x = arg: assert arg == "y"; 123;
              |       ^
-            3|
+            3| in
 
        error: assertion '(arg == "y")' failed
        at /pwd/lang/eval-fail-assert.nix:2:12:
-            1| let {
+            1| let
             2|   x = arg: assert arg == "y"; 123;
              |            ^
-            3|
+            3| in
diff --git a/tests/functional/lang/eval-fail-assert.nix b/tests/functional/lang/eval-fail-assert.nix
index 3b7a1e8bf..405adedbd 100644
--- a/tests/functional/lang/eval-fail-assert.nix
+++ b/tests/functional/lang/eval-fail-assert.nix
@@ -1,5 +1,4 @@
-let {
+let
   x = arg: assert arg == "y"; 123;
-
-  body = x "x";
-}
\ No newline at end of file
+in
+x "x"
diff --git a/tests/functional/lang/eval-fail-blackhole.err.exp b/tests/functional/lang/eval-fail-blackhole.err.exp
index 95e33a5fe..91fd293f3 100644
--- a/tests/functional/lang/eval-fail-blackhole.err.exp
+++ b/tests/functional/lang/eval-fail-blackhole.err.exp
@@ -1,14 +1,6 @@
-error:
-       … while evaluating the attribute 'body'
-         at /pwd/lang/eval-fail-blackhole.nix:2:3:
-            1| let {
-            2|   body = x;
-             |   ^
-            3|   x = y;
-
-       error: infinite recursion encountered
-       at /pwd/lang/eval-fail-blackhole.nix:3:7:
-            2|   body = x;
-            3|   x = y;
+error: infinite recursion encountered
+       at /pwd/lang/eval-fail-blackhole.nix:2:7:
+            1| let
+            2|   x = y;
              |       ^
-            4|   y = x;
+            3|   y = x;
diff --git a/tests/functional/lang/eval-fail-blackhole.nix b/tests/functional/lang/eval-fail-blackhole.nix
index 81133b511..f7519a89b 100644
--- a/tests/functional/lang/eval-fail-blackhole.nix
+++ b/tests/functional/lang/eval-fail-blackhole.nix
@@ -1,5 +1,5 @@
-let {
-  body = x;
+let
   x = y;
   y = x;
-}
+in
+x
diff --git a/tests/functional/lang/eval-fail-remove.err.exp b/tests/functional/lang/eval-fail-remove.err.exp
index 292b3c3f3..0ae9c1256 100644
--- a/tests/functional/lang/eval-fail-remove.err.exp
+++ b/tests/functional/lang/eval-fail-remove.err.exp
@@ -1,15 +1,7 @@
-error:
-       … while evaluating the attribute 'body'
-         at /pwd/lang/eval-fail-remove.nix:4:3:
-            3|
-            4|   body = (removeAttrs attrs ["x"]).x;
+error: attribute 'x' missing
+       at /pwd/lang/eval-fail-remove.nix:4:3:
+            3| in
+            4|   (removeAttrs attrs ["x"]).x
              |   ^
-            5| }
-
-       error: attribute 'x' missing
-       at /pwd/lang/eval-fail-remove.nix:4:10:
-            3|
-            4|   body = (removeAttrs attrs ["x"]).x;
-             |          ^
-            5| }
+            5|
        Did you mean y?
diff --git a/tests/functional/lang/eval-fail-remove.nix b/tests/functional/lang/eval-fail-remove.nix
index 539e0eb0a..3ea7b1c86 100644
--- a/tests/functional/lang/eval-fail-remove.nix
+++ b/tests/functional/lang/eval-fail-remove.nix
@@ -1,5 +1,4 @@
-let {
+let
   attrs = {x = 123; y = 456;};
-
-  body = (removeAttrs attrs ["x"]).x;
-}
\ No newline at end of file
+in
+  (removeAttrs attrs ["x"]).x
diff --git a/tests/functional/lang/eval-fail-scope-5.err.exp b/tests/functional/lang/eval-fail-scope-5.err.exp
index b0b05cad7..4dcfb5321 100644
--- a/tests/functional/lang/eval-fail-scope-5.err.exp
+++ b/tests/functional/lang/eval-fail-scope-5.err.exp
@@ -1,28 +1,21 @@
 error:
-       … while evaluating the attribute 'body'
-         at /pwd/lang/eval-fail-scope-5.nix:8:3:
-            7|
-            8|   body = f {};
-             |   ^
-            9|
-
        … from call site
-         at /pwd/lang/eval-fail-scope-5.nix:8:10:
-            7|
-            8|   body = f {};
-             |          ^
-            9|
+         at /pwd/lang/eval-fail-scope-5.nix:7:3:
+            6| in
+            7|   f {}
+             |   ^
+            8|
 
        … while calling 'f'
-         at /pwd/lang/eval-fail-scope-5.nix:6:7:
-            5|
-            6|   f = {x ? y, y ? x}: x + y;
+         at /pwd/lang/eval-fail-scope-5.nix:5:7:
+            4|
+            5|   f = {x ? y, y ? x}: x + y;
              |       ^
-            7|
+            6| in
 
        error: infinite recursion encountered
-       at /pwd/lang/eval-fail-scope-5.nix:6:12:
-            5|
-            6|   f = {x ? y, y ? x}: x + y;
+       at /pwd/lang/eval-fail-scope-5.nix:5:12:
+            4|
+            5|   f = {x ? y, y ? x}: x + y;
              |            ^
-            7|
+            6| in
diff --git a/tests/functional/lang/eval-fail-scope-5.nix b/tests/functional/lang/eval-fail-scope-5.nix
index f89a65a99..dd98246b5 100644
--- a/tests/functional/lang/eval-fail-scope-5.nix
+++ b/tests/functional/lang/eval-fail-scope-5.nix
@@ -1,10 +1,7 @@
-let {
-
+let
   x = "a";
   y = "b";
 
   f = {x ? y, y ? x}: x + y;
-
-  body = f {};
-
-}
+in
+  f {}
diff --git a/tests/functional/lang/eval-okay-arithmetic.nix b/tests/functional/lang/eval-okay-arithmetic.nix
index 7e9e6a0b6..534e9d169 100644
--- a/tests/functional/lang/eval-okay-arithmetic.nix
+++ b/tests/functional/lang/eval-okay-arithmetic.nix
@@ -1,6 +1,6 @@
 with import ./lib.nix;
 
-let {
+let
 
   /* Supposedly tail recursive version:
 
@@ -15,7 +15,8 @@ let {
 
   err = abort "urgh";
 
-  body = sum
+in
+  sum
     [ (sum (range 1 50))
       (123 + 456)
       (0 + -10 + -(-11) + -x)
@@ -54,6 +55,5 @@ let {
       (if "aa" < "ab" then 1 else err)
       (if "aa" < "aa" then err else 1)
       (if "foo" < "foobar" then 1 else err)
-    ];
+    ]
 
-}
diff --git a/tests/functional/lang/eval-okay-attrs.nix b/tests/functional/lang/eval-okay-attrs.nix
index 810b31a5d..7d5c04583 100644
--- a/tests/functional/lang/eval-okay-attrs.nix
+++ b/tests/functional/lang/eval-okay-attrs.nix
@@ -1,5 +1,8 @@
-let {
+let
   as = { x = 123; y = 456; } // { z = 789; } // { z = 987; };
-
-  body = if as ? a then as.a else assert as ? z; as.z;
-}
+in
+if as ? a then
+  as.a
+else
+  assert as ? z;
+  as.z
diff --git a/tests/functional/lang/eval-okay-attrs2.nix b/tests/functional/lang/eval-okay-attrs2.nix
index 9e06b83ac..925dc1859 100644
--- a/tests/functional/lang/eval-okay-attrs2.nix
+++ b/tests/functional/lang/eval-okay-attrs2.nix
@@ -1,10 +1,11 @@
-let {
+let
   as = { x = 123; y = 456; } // { z = 789; } // { z = 987; };
 
   A = "a";
   Z = "z";
 
-  body = if builtins.hasAttr A as
-         then builtins.getAttr A as
-         else assert builtins.hasAttr Z as; builtins.getAttr Z as;
-}
+in
+if builtins.hasAttr A as then
+  builtins.getAttr A as
+else
+  assert builtins.hasAttr Z as; builtins.getAttr Z as
diff --git a/tests/functional/lang/eval-okay-builtins.nix b/tests/functional/lang/eval-okay-builtins.nix
index e9d65e88a..551eb3517 100644
--- a/tests/functional/lang/eval-okay-builtins.nix
+++ b/tests/functional/lang/eval-okay-builtins.nix
@@ -1,12 +1,11 @@
 assert builtins ? currentSystem;
 assert !builtins ? __currentSystem;
 
-let {
+let
 
   x = if builtins ? dirOf then builtins.dirOf /foo/bar else "";
 
   y = if builtins ? fnord then builtins.fnord "foo" else "";
 
-  body = x + y;
-  
-}
+in
+x + y
diff --git a/tests/functional/lang/eval-okay-flatten.nix b/tests/functional/lang/eval-okay-flatten.nix
index fe911e968..b1fb0f878 100644
--- a/tests/functional/lang/eval-okay-flatten.nix
+++ b/tests/functional/lang/eval-okay-flatten.nix
@@ -1,8 +1,8 @@
 with import ./lib.nix;
 
-let {
+let
 
   l = ["1" "2" ["3" ["4"] ["5" "6"]] "7"];
 
-  body = concat (flatten l);
-}
+in
+concat (flatten l)
diff --git a/tests/functional/lang/eval-okay-list.nix b/tests/functional/lang/eval-okay-list.nix
index d433bcf90..eb6e60f23 100644
--- a/tests/functional/lang/eval-okay-list.nix
+++ b/tests/functional/lang/eval-okay-list.nix
@@ -1,7 +1,3 @@
 with import ./lib.nix;
 
-let {
-
-  body = concat ["foo" "bar" "bla" "test"];
-    
-}
\ No newline at end of file
+concat ["foo" "bar" "bla" "test"]
diff --git a/tests/functional/lang/eval-okay-remove.nix b/tests/functional/lang/eval-okay-remove.nix
index 4ad5ba897..c2e06b3d2 100644
--- a/tests/functional/lang/eval-okay-remove.nix
+++ b/tests/functional/lang/eval-okay-remove.nix
@@ -1,5 +1,4 @@
-let {
+let
   attrs = {x = 123; y = 456;};
-
-  body = (removeAttrs attrs ["x"]).y;
-}
\ No newline at end of file
+in
+(removeAttrs attrs ["x"]).y
diff --git a/tests/functional/lang/eval-okay-scope-4.nix b/tests/functional/lang/eval-okay-scope-4.nix
index dc8243bc8..c1e4e6683 100644
--- a/tests/functional/lang/eval-okay-scope-4.nix
+++ b/tests/functional/lang/eval-okay-scope-4.nix
@@ -1,10 +1,7 @@
-let {
-
+let
   x = "a";
   y = "b";
 
   f = {x ? y, y ? x}: x + y;
-
-  body = f {x = "c";} + f {y = "d";};
-
-}
+in
+f {x = "c";} + f {y = "d";}
diff --git a/tests/functional/lang/eval-okay-scope-6.nix b/tests/functional/lang/eval-okay-scope-6.nix
index 0995d4e7e..1cd338cda 100644
--- a/tests/functional/lang/eval-okay-scope-6.nix
+++ b/tests/functional/lang/eval-okay-scope-6.nix
@@ -1,7 +1,5 @@
-let {
+let
 
   f = {x ? y, y ? x}: x + y;
-
-  body = f {x = "c";} + f {y = "d";};
-
-}
+in
+f {x = "c";} + f {y = "d";}
diff --git a/tests/functional/lang/eval-okay-with.nix b/tests/functional/lang/eval-okay-with.nix
index 033e8d3ab..a17d0e7b9 100644
--- a/tests/functional/lang/eval-okay-with.nix
+++ b/tests/functional/lang/eval-okay-with.nix
@@ -1,4 +1,4 @@
-let {
+let
 
   a = "xyzzy";
 
@@ -15,5 +15,5 @@ let {
 
   y = with as; with bs; a + b;
 
-  body = x + y;
-}
+in
+x + y
diff --git a/tests/functional/lang/parse-fail-dup-attrs-2.nix b/tests/functional/lang/parse-fail-dup-attrs-2.nix
index 864d9865e..2b3b4ccde 100644
--- a/tests/functional/lang/parse-fail-dup-attrs-2.nix
+++ b/tests/functional/lang/parse-fail-dup-attrs-2.nix
@@ -1,4 +1,4 @@
-let {
+rec {
 
   as = {
     x = 123;
@@ -9,5 +9,5 @@ let {
     x = 789;
     inherit (as) x;
   };
-  
+
 }
diff --git a/tests/functional/lang/parse-fail-dup-attrs-3.nix b/tests/functional/lang/parse-fail-dup-attrs-3.nix
index 114d19779..732fbf9e7 100644
--- a/tests/functional/lang/parse-fail-dup-attrs-3.nix
+++ b/tests/functional/lang/parse-fail-dup-attrs-3.nix
@@ -1,4 +1,4 @@
-let {
+rec {
 
   as = {
     x = 123;
@@ -9,5 +9,5 @@ let {
     x = 789;
     inherit (as) x;
   };
-  
+
 }
diff --git a/tests/functional/lang/parse-fail-regression-20060610.err.exp b/tests/functional/lang/parse-fail-regression-20060610.err.exp
index 6ae7c01bf..59fa1f08f 100644
--- a/tests/functional/lang/parse-fail-regression-20060610.err.exp
+++ b/tests/functional/lang/parse-fail-regression-20060610.err.exp
@@ -1,6 +1,6 @@
 error: undefined variable 'gcc'
-       at «stdin»:9:13:
-            8|   body = ({
-            9|     inherit gcc;
-             |             ^
-           10|   }).gcc;
+       at «stdin»:9:11:
+            8| ({
+            9|   inherit gcc;
+             |           ^
+           10| }).gcc
diff --git a/tests/functional/lang/parse-fail-regression-20060610.nix b/tests/functional/lang/parse-fail-regression-20060610.nix
index b1934f7e1..b5f4a2682 100644
--- a/tests/functional/lang/parse-fail-regression-20060610.nix
+++ b/tests/functional/lang/parse-fail-regression-20060610.nix
@@ -1,11 +1,10 @@
-let {
+let
   x =
     {gcc}:
     {
       inherit gcc;
     };
-
-  body = ({
-    inherit gcc;
-  }).gcc;
-}
+in
+({
+  inherit gcc;
+}).gcc
diff --git a/tests/functional/lang/parse-fail-undef-var-2.nix b/tests/functional/lang/parse-fail-undef-var-2.nix
index c10a52b1e..c2e959495 100644
--- a/tests/functional/lang/parse-fail-undef-var-2.nix
+++ b/tests/functional/lang/parse-fail-undef-var-2.nix
@@ -1,7 +1,6 @@
-let {
+let
 
   f = {x, y : ["baz" "bar" z "bat"]}: x + y;
 
-  body = f {x = "foo"; y = "bar";};
-
-}
+in
+f {x = "foo"; y = "bar";}