diff --git a/desktop/sources/scripts/library.js b/desktop/sources/scripts/library.js
index 647d6a6..43649e4 100644
--- a/desktop/sources/scripts/library.js
+++ b/desktop/sources/scripts/library.js
@@ -24,6 +24,56 @@ function Library (ronin) {
     // TODO: Closes Ronin
   }
 
+  // Logic
+
+  this.gt = (a, b) => {
+    return a > b
+  }
+
+  this.lt = (a, b) => {
+    return a < b
+  }
+
+  this.eq = (a, b) => {
+    return a === b
+  }
+
+  this.and = (...args) => {
+    for (let i = 0; i < args.length; i++) {
+      if (!args[i]) {
+        return args[i]
+      }
+    }
+    return args[args.length - 1]
+  }
+
+  this.or = (...args) => {
+    for (let i = 0; i < args.length; i++) {
+      if (args[i]) {
+        return args[i]
+      }
+    }
+    return args[args.length - 1]
+  }
+
+  // Arrays
+
+  this.map = (fn, arr) => {
+    return arr.map(fn)
+  }
+
+  this.filter = (fn, arr) => {
+    return arr.filter(fn)
+  }
+
+  this.first = (arr) => {
+    return arr[0]
+  }
+
+  this.rest = ([_, ...arr]) => {
+    return arr
+  }
+
   // Rects
 
   this.pos = (x, y, t = 'pos') => {
@@ -105,7 +155,12 @@ function Library (ronin) {
   this.mul = function (a, b) {
     return a * b
   }
+
   this.div = function (a, b) {
     return a / b
   }
+
+  this.mod = function (a, b) {
+    return a % b
+  }
 }
diff --git a/desktop/sources/scripts/lisp.js b/desktop/sources/scripts/lisp.js
index f30fde6..0cb4b73 100644
--- a/desktop/sources/scripts/lisp.js
+++ b/desktop/sources/scripts/lisp.js
@@ -45,6 +45,13 @@ function Lisp (input, lib) {
 
         return interpret(input[2], new Context(lambdaScope, context))
       }
+    },
+
+    if: function (input, context) {
+      if (interpret(input[1], context)) {
+        return interpret(input[2], context)
+      }
+      return interpret(input[3], context)
     }
   }
 
diff --git a/examples/arrays.lisp b/examples/arrays.lisp
new file mode 100644
index 0000000..fa87526
--- /dev/null
+++ b/examples/arrays.lisp
@@ -0,0 +1,19 @@
+(echo (map (lambda (a) (add a 1)) (1 2 3)))
+
+(
+  (echo (first (1 2 3)))
+  (echo (rest (1 2 3)))
+)
+
+(echo
+  (filter 
+    (lambda (a) (eq 0 (mod a 2))) 
+    (1 2 3 4 5))
+)
+
+(
+  (clear) 
+  (map (lambda (a)
+    (stroke (rect (mul a 30) 20 50 50) 1 "red"))
+    (5 10 15 20))
+)
\ No newline at end of file
diff --git a/examples/logic.lisp b/examples/logic.lisp
new file mode 100644
index 0000000..dc22f79
--- /dev/null
+++ b/examples/logic.lisp
@@ -0,0 +1,11 @@
+(
+  (echo (lt 3 4))
+
+  (echo (and 1 2 true 4))
+
+  (echo (and 1 false 2))
+
+  (echo (or false false 2 false))
+
+  (if (gt 1 2) (echo "ok") (echo "not ok"))
+)
\ No newline at end of file