diff --git a/eo-runtime/src/main/eo/org/eolang/negative-infinity.eo b/eo-runtime/src/main/eo/org/eolang/negative-infinity.eo
index 2a28b8d992..3a9e5763ee 100644
--- a/eo-runtime/src/main/eo/org/eolang/negative-infinity.eo
+++ b/eo-runtime/src/main/eo/org/eolang/negative-infinity.eo
@@ -78,17 +78,19 @@
 
     [num] > is-nan-or-zero
       or. > @
-        is-nan num
-        num.eq -0.0
-        num.eq 0.0
+        or.
+          or.
+            is-nan num
+            num.eq -0.0
+          num.eq 0.0
         num.eq 0
     if. > @
       is-nan-or-zero value
       nan
-        if.
-          is-num-gt-zero value
-          negative-infinity
-          positive-infinity
+      if.
+        is-num-gt-zero value
+        negative-infinity
+        positive-infinity
 
   # Sum of $ and x
   [x] > plus
@@ -116,12 +118,11 @@
       not. > @
         num.eq num
     if. > @
-      if.
-        or.
-          is-nan value
-          value.as-bytes.eq neg-inf-as-bytes
-        nan
-        negative-infinity
+      or.
+        is-nan value
+        value.as-bytes.eq neg-inf-as-bytes
+      nan
+      negative-infinity
 
   # Quotient of the division of $ by x
   [x] > div
@@ -133,8 +134,9 @@
 
     [num] > is-nan-or-infinite
       or. > @
-        is-nan num
-        num.eq positive-infinity
+        or.
+          is-nan num
+          num.eq positive-infinity
         num.eq negative-infinity
 
     [num] > is-num-gte-zero
diff --git a/eo-runtime/src/main/eo/org/eolang/positive-infinity.eo b/eo-runtime/src/main/eo/org/eolang/positive-infinity.eo
index 87ca7c0eae..64dfc8ea19 100644
--- a/eo-runtime/src/main/eo/org/eolang/positive-infinity.eo
+++ b/eo-runtime/src/main/eo/org/eolang/positive-infinity.eo
@@ -70,9 +70,11 @@
 
     [num] > is-nan-or-zero
       or. > @
-        is-nan num
-        num.eq -0.0
-        num.eq 0.0
+        or.
+          or.
+            is-nan num
+            num.eq -0.0
+          num.eq 0.0
         num.eq 0
 
     [num] > is-num-gt-zero
@@ -132,8 +134,9 @@
 
     [num] > is-nan-or-infinite
       or. > @
-        is-nan num
-        num.eq positive-infinity
+        or.
+          is-nan num
+          num.eq positive-infinity
         num.eq negative-infinity
 
     [num] > is-num-gte-zero
diff --git a/eo-runtime/src/main/java/EOorg/EOeolang/EOfloat$EOplus.java b/eo-runtime/src/main/java/EOorg/EOeolang/EOfloat$EOplus.java
index 31a1d01259..24466a37bc 100644
--- a/eo-runtime/src/main/java/EOorg/EOeolang/EOfloat$EOplus.java
+++ b/eo-runtime/src/main/java/EOorg/EOeolang/EOfloat$EOplus.java
@@ -58,8 +58,10 @@ public class EOfloat$EOplus extends PhDefault {
             new AtComposite(
                 this,
                 rho -> new Data.ToPhi(
-                    new Param(rho).strong(Double.class)
-                        + new Param(rho, "x").strong(Double.class)
+                    Double.sum(
+                        new Param(rho).strong(Double.class),
+                        new Param(rho, "x").strong(Double.class)
+                    )
                 )
             )
         );
diff --git a/eo-runtime/src/main/java/EOorg/EOeolang/EOint$EOplus.java b/eo-runtime/src/main/java/EOorg/EOeolang/EOint$EOplus.java
index 3d52b9a944..ffc74114fd 100644
--- a/eo-runtime/src/main/java/EOorg/EOeolang/EOint$EOplus.java
+++ b/eo-runtime/src/main/java/EOorg/EOeolang/EOint$EOplus.java
@@ -58,8 +58,10 @@ public class EOint$EOplus extends PhDefault {
             new AtComposite(
                 this,
                 rho -> new Data.ToPhi(
-                    new Param(rho).strong(Long.class)
-                        + new Param(rho, "x").strong(Long.class)
+                    Long.sum(
+                        new Param(rho).strong(Long.class),
+                        new Param(rho, "x").strong(Long.class)
+                    )
                 )
             )
         );
diff --git a/eo-runtime/src/test/eo/org/eolang/bool-tests.eo b/eo-runtime/src/test/eo/org/eolang/bool-tests.eo
index 9a673f6347..dcf1f87849 100644
--- a/eo-runtime/src/test/eo/org/eolang/bool-tests.eo
+++ b/eo-runtime/src/test/eo/org/eolang/bool-tests.eo
@@ -37,14 +37,6 @@
       TRUE
       42
 
-[] > joins-many-ands
-  and. > @
-    TRUE
-    5.lt 10
-    4.gt -6
-    TRUE
-    0.eq 0
-
 [] > forks-on-condition
   eq. > @
     if.
@@ -67,45 +59,6 @@
             x.as-int.plus 1
       11
 
-# tests that bool.and stops calculations if its i'th
-# object is false (including the base object)
-[] > and-short-circuiting
-  memory 0 > mFirst
-  memory 0 > mThird
-  and. > res
-    not.
-      and.
-        (mFirst.write 1).eq 100
-        (mFirst.write 2).eq 2
-        (mFirst.write 3).eq 3
-    not.
-      and.
-        (mThird.write 1).eq 1
-        (mThird.write 2).eq 2
-        (mThird.write 3).eq 300
-        (mThird.write 4).eq 4
-    mFirst.eq 1
-    mThird.eq 3
-  nop > @
-
-# tests that bool.or stops calculations if its i'th
-# object is true (including the base object)
-[] > or-short-circuiting
-  memory 0 > mFirst
-  memory 0 > mThird
-  and. > @
-    or.
-      (mFirst.write 1).eq 1
-      mFirst.write 2
-      mFirst.write 3
-    or.
-      (mThird.write 1).eq 100
-      (mThird.write 2).eq 200
-      (mThird.write 3).eq 3
-      mThird.write 4
-    mFirst.eq 1
-    mThird.eq 3
-
 [] > compares-bool-to-bytes
   and. > @
     TRUE.eq 01-
diff --git a/eo-runtime/src/test/eo/org/eolang/bytes-tests.eo b/eo-runtime/src/test/eo/org/eolang/bytes-tests.eo
index 926bfaa328..4b87e289a6 100644
--- a/eo-runtime/src/test/eo/org/eolang/bytes-tests.eo
+++ b/eo-runtime/src/test/eo/org/eolang/bytes-tests.eo
@@ -162,15 +162,6 @@
       -7.as-bytes.and (7.as-bytes)
       -2.as-bytes
 
-[] > and-with-vararg
-  eq. > @
-    as-int.
-      and.
-        0.as-bytes
-        5.as-bytes
-        10.as-bytes
-    0
-
 [] > or-with-zero
   not. > @
     eq.
@@ -195,16 +186,6 @@
       -7.as-bytes.or (23.as-bytes)
       0.as-bytes
 
-[] > or-with-vararg
-  not. > @
-    eq.
-      as-int.
-        or.
-          256.as-bytes
-          5.as-bytes
-          10.as-bytes
-      -1
-
 [] > xor-with-zero
   not. > @
     eq.
@@ -229,16 +210,6 @@
       -36.as-bytes.xor (43.as-bytes)
       8.as-bytes
 
-[] > xor-with-vararg
-  not. > @
-    eq.
-      as-int.
-        xor.
-          256.as-bytes
-          5.as-bytes
-          10.as-bytes
-      -1
-
 [] > not-with-zero
   not. > @
     eq.
diff --git a/eo-runtime/src/test/eo/org/eolang/float-tests.eo b/eo-runtime/src/test/eo/org/eolang/float-tests.eo
index 26905fde41..34109531c8 100644
--- a/eo-runtime/src/test/eo/org/eolang/float-tests.eo
+++ b/eo-runtime/src/test/eo/org/eolang/float-tests.eo
@@ -232,15 +232,6 @@
       0.311985
     -0.1792353825
 
-[] > times-multiple
-  eq. > @
-    times.
-      -0.5745
-      0.311985
-      3.232
-      -2.532
-    1.4667591307996803
-
 [] > add-test
   eq. > @
     plus.
@@ -248,28 +239,18 @@
       311.985
     886.485
 
-[] > add-multiple-test
-  eq. > @
-    plus.
-      574.5
-      311.985
-      -101.1
-      1.001
-    786.386
-
 [] > add-wrong-args
-  eq. > @
-    try
-      []
-        plus. > @
-          574.5
-          311
-          -101.1
-          1.001
-      [e]
-        e > @
-      nop
-    "The 1th argument of 'float.plus' is not a(n) Double: 311"
+  not. > @
+    eq.
+      try
+        []
+          plus. > @
+            42.5
+            24
+        [e]
+          e > @
+        nop
+      66.5
 
 [] > neg-test
   eq. > @
@@ -283,15 +264,6 @@
       311.985
     262.515
 
-[] > sub-multiple-test
-  eq. > @
-    minus.
-      574.5
-      311.985
-      -24.347
-      3542.2238
-    -3255.3618
-
 [] > div-test
   eq. > @
     div.
@@ -299,14 +271,6 @@
       0.5
     31.0
 
-[] > div-multiple
-  eq. > @
-    div.
-      15.5
-      0.5
-      0.2
-    155.0
-
 [] > zero-div-zero-as-bytes-is-equal-to-nan-as-bytes
   eq. > @
     (0.0.div 0.0).as-bytes
diff --git a/eo-runtime/src/test/eo/org/eolang/heap-tests.eo b/eo-runtime/src/test/eo/org/eolang/heap-tests.eo
index d3f9bbea78..bcd17e6195 100644
--- a/eo-runtime/src/test/eo/org/eolang/heap-tests.eo
+++ b/eo-runtime/src/test/eo/org/eolang/heap-tests.eo
@@ -89,12 +89,13 @@
   p2.sub 1 > p3
   eq. > @
     and.
-      (p1.block 6).write ("HELLO!".as-bytes)
-      eq.
-        p2.block
-          2
-          [b] (b.as-string > @)
-        "O!"
+      and.
+        (p1.block 6).write ("HELLO!".as-bytes)
+        eq.
+          p2.block
+            2
+            [b] (b.as-string > @)
+          "O!"
       eq.
         p3.block
           2
diff --git a/eo-runtime/src/test/eo/org/eolang/int-tests.eo b/eo-runtime/src/test/eo/org/eolang/int-tests.eo
index 9bb898693f..df90b096e7 100644
--- a/eo-runtime/src/test/eo/org/eolang/int-tests.eo
+++ b/eo-runtime/src/test/eo/org/eolang/int-tests.eo
@@ -131,11 +131,15 @@
 [] > int-equal-to-nan-and-infinites-is-false
   eq. > @
     and.
-      (0.eq nan).eq FALSE
-      (0.eq positive-infinity).eq FALSE
-      (0.eq negative-infinity).eq FALSE
-      (42.eq nan).eq FALSE
-      (42.eq positive-infinity).eq FALSE
+      and.
+        and.
+          and.
+            and.
+              (0.eq nan).eq FALSE
+              (0.eq positive-infinity).eq FALSE
+            (0.eq negative-infinity).eq FALSE
+          (42.eq nan).eq FALSE
+        (42.eq positive-infinity).eq FALSE
       (42.eq negative-infinity).eq FALSE
     TRUE
 
@@ -220,7 +224,7 @@
       [e]
         e > @
       nop
-    "Can't divide by "
+    "Can't divide by integer zero"
 
 # Checks that division by one returns the dividend
 [] > division-by-one
@@ -246,21 +250,6 @@
     1.div 5
     0
 
-[] > div-with-multiple
-  eq. > @
-    100.div 5 2 -5
-    -2
-
-[] > div-wrong-args
-  eq. > @
-    try
-      []
-        100.div 1 2 3.0 > @
-      [e]
-        e > @
-      nop
-    "The 3th argument of 'int.div' is not a(n) Long: 3.0"
-
 [] > to-bytes-and-backwards
   eq. > @
     as-int.
@@ -278,42 +267,7 @@
     42.as-bytes
     42
 
-[] > sum-up-several-arguments
-  eq. > @
-    1982
-    1000.plus 900 80 2
-
-[] > sum-up-wrong-args
-  eq. > @
-    try
-      []
-        100.plus 1 2 3.0 > @
-      [e]
-        e > @
-      nop
-    "The 3th argument of 'int.plus' is not a(n) Long: 3.0"
-
-[] > multiply-several-arguments
-  eq. > @
-    1000.times 2 5
-    10000
-
-[] > multiply-wrong-args
-  eq. > @
-    try
-      []
-        100.times 1 2 3.0 > @
-      [e]
-        e > @
-      nop
-    "The 3th argument of 'int.times' is not a(n) Long: 3.0"
-
 [] > multiply-by-zero
   eq. > @
     1000.times 0
     0
-
-[] > minus-multiple-args
-  eq. > @
-    123.minus -12 135 235 0
-    -235
diff --git a/eo-runtime/src/test/eo/org/eolang/positive-infinity-tests.eo b/eo-runtime/src/test/eo/org/eolang/positive-infinity-tests.eo
index 5a7c37ab2a..b02ba03b61 100644
--- a/eo-runtime/src/test/eo/org/eolang/positive-infinity-tests.eo
+++ b/eo-runtime/src/test/eo/org/eolang/positive-infinity-tests.eo
@@ -177,17 +177,27 @@
   negative-infinity > neg-inf
   eq. > @
     and.
-      (0.0.eq nan).eq FALSE
-      (0.0.eq pos-inf).eq FALSE
-      (0.0.eq neg-inf).eq FALSE
-      (42.5.eq nan).eq FALSE
-      (42.5.eq pos-inf).eq FALSE
-      (42.5.eq neg-inf).eq FALSE
-      (0.0.eq nan).eq FALSE
-      (0.0.eq pos-inf).eq FALSE
-      (0.0.eq neg-inf).eq FALSE
-      (42.5.eq nan).eq FALSE
-      (42.5.eq pos-inf).eq FALSE
+      and.
+        and.
+          and.
+            and.
+              and.
+                and.
+                  and.
+                    and.
+                      and.
+                        and.
+                          (0.0.eq nan).eq FALSE
+                          (0.0.eq pos-inf).eq FALSE
+                        (0.0.eq neg-inf).eq FALSE
+                      (42.5.eq nan).eq FALSE
+                    (42.5.eq pos-inf).eq FALSE
+                  (42.5.eq neg-inf).eq FALSE
+                (0.0.eq nan).eq FALSE
+              (0.0.eq pos-inf).eq FALSE
+            (0.0.eq neg-inf).eq FALSE
+          (42.5.eq nan).eq FALSE
+        (42.5.eq pos-inf).eq FALSE
       (42.5.eq neg-inf).eq FALSE
     TRUE
 
diff --git a/eo-runtime/src/test/eo/org/eolang/runtime-tests.eo b/eo-runtime/src/test/eo/org/eolang/runtime-tests.eo
index 4dee9c952a..f0885ab4d4 100644
--- a/eo-runtime/src/test/eo/org/eolang/runtime-tests.eo
+++ b/eo-runtime/src/test/eo/org/eolang/runtime-tests.eo
@@ -129,8 +129,9 @@
 [] > positive-object-vertices
   eq. > @
     or.
-      42.<.eq (42.<)
-      "Hello".<.eq ("Hello".<)
+      or.
+        42.<.eq (42.<)
+        "Hello".<.eq ("Hello".<)
       45-1F-E7.<.eq (45-1F-E7.<)
     FALSE
 
@@ -145,10 +146,13 @@
   [x] > a
   eq. > @
     or.
-      (2.plus 3).<.eq (5.<)
-      42.<.eq (42.0.<)
-      45-1F-E8.<.eq (45-1F-E8-83.<)
-      (a 5).<.eq ((a 5).<)
+      or.
+        or.
+          or.
+            (2.plus 3).<.eq (5.<)
+            42.<.eq (42.0.<)
+          45-1F-E8.<.eq (45-1F-E8-83.<)
+        (a 5).<.eq ((a 5).<)
       (* 1 2 3).<.eq ((* 1 2 3).<)
     FALSE
 
diff --git a/eo-runtime/src/test/eo/org/eolang/tuple-tests.eo b/eo-runtime/src/test/eo/org/eolang/tuple-tests.eo
index d5352611c5..6aeb5520ce 100644
--- a/eo-runtime/src/test/eo/org/eolang/tuple-tests.eo
+++ b/eo-runtime/src/test/eo/org/eolang/tuple-tests.eo
@@ -90,15 +90,17 @@
     * 1 2 3
     "with"
   and. > @
-    eq.
-      arr.at 0
-      1
-    eq.
-      arr.at 1
-      2
-    eq.
-      arr.at 2
-      3
+    and.
+      and.
+        eq.
+          arr.at 0
+          1
+        eq.
+          arr.at 1
+          2
+      eq.
+        arr.at 2
+        3
     eq.
       arr.at 3
       "with"
@@ -118,12 +120,13 @@
 [] > tuple-fluent-with
   ((*.with 1).with 2).with 3 > arr
   and. > @
-    eq.
-      arr.at 0
-      1
-    eq.
-      arr.at 1
-      2
+    and.
+      eq.
+        arr.at 0
+        1
+      eq.
+        arr.at 1
+        2
     eq.
       arr.at 2
       3
@@ -134,12 +137,13 @@
   .with 2
   .with 3 > arr
   and. > @
-    eq.
-      arr.at 0
-      1
-    eq.
-      arr.at 1
-      2
+    and.
+      eq.
+        arr.at 0
+        1
+      eq.
+        arr.at 1
+        2
     eq.
       arr.at 2
       3
@@ -167,12 +171,13 @@
   .with 2
   .with 3 > arr
   and. > @
-    eq.
-      arr.at 0
-      1
-    eq.
-      arr.at 1
-      2
+    and.
+      eq.
+        arr.at 0
+        1
+      eq.
+        arr.at 1
+        2
     eq.
       arr.at 2
       3