diff --git a/scratchpad/src/main/scala/com/htmlism/scratchpad/Reg.scala b/scratchpad/src/main/scala/com/htmlism/scratchpad/Reg.scala
new file mode 100644
index 0000000..a8151cf
--- /dev/null
+++ b/scratchpad/src/main/scala/com/htmlism/scratchpad/Reg.scala
@@ -0,0 +1,8 @@
+package com.htmlism.scratchpad
+
+trait Reg[A]:
+  def hello: Boolean
+
+given tuple2reg[A, B](using a: Reg[A], b: Reg[B]): Reg[(A, B)] with
+  def hello: Boolean =
+    true
diff --git a/scratchpad/src/main/scala/com/htmlism/scratchpad/ScratchPad.scala b/scratchpad/src/main/scala/com/htmlism/scratchpad/ScratchPad.scala
index f478325..585bc14 100644
--- a/scratchpad/src/main/scala/com/htmlism/scratchpad/ScratchPad.scala
+++ b/scratchpad/src/main/scala/com/htmlism/scratchpad/ScratchPad.scala
@@ -17,18 +17,28 @@ object Write:
   implicit val writeLease: Lease[Write] =
     new Lease { }
 
-class Reg[A]
-
 object ScratchPad:
+  def reg[A : Reg]: PartialUsing[A] =
+    new PartialUsing[A]
+
+  class PartialUsing[A](using a: Reg[A]):
+    def use[B](f: Reg[A] => B): B =
+      f(a)
+
+  reg[Accumulator].use { a =>
+    AsmProgram(startA, "")
+      .widen[RegisterX]
+  }
+
   trait ReadWrite[A] extends Read[A] with Write[A]
 
-  val startA =
+  lazy val startA =
     ??? : StatefulRegister[Accumulator, Unknown]
 
-  val startX =
+  lazy val startX =
     ??? : StatefulRegister[RegisterX, Unknown]
 
-  val startY =
+  lazy val startY =
     ??? : StatefulRegister[RegisterY, Unknown]
 
   (AsmProgram(startA, "") : AsmProgram[Accumulator, Unknown, String])
@@ -45,19 +55,20 @@ object ScratchPad:
 class Accumulator
 
 object Accumulator extends Accumulator:
-  implicit val registerA: Reg[Accumulator] =
-    new Reg
+  given registerA: Reg[Accumulator] with
+    def hello: Boolean =
+      true
 
 class RegisterX
 
 object RegisterX:
-  implicit val registerX: Reg[RegisterX] =
-    new Reg
+  given registerX: Reg[RegisterX] with
+    def hello: Boolean =
+      true
 
 class RegisterY
 
 object RegisterY:
-  implicit val registerY: Reg[RegisterY] =
-    new Reg
-
-trait StatefulRegister[A : Reg, F <: MutationStatus]
+  given registerY: Reg[RegisterY] with
+    def hello: Boolean =
+      true
diff --git a/scratchpad/src/main/scala/com/htmlism/scratchpad/StatefulRegister.scala b/scratchpad/src/main/scala/com/htmlism/scratchpad/StatefulRegister.scala
new file mode 100644
index 0000000..ead3a62
--- /dev/null
+++ b/scratchpad/src/main/scala/com/htmlism/scratchpad/StatefulRegister.scala
@@ -0,0 +1,4 @@
+package com.htmlism.scratchpad
+
+
+trait StatefulRegister[A : Reg, F <: MutationStatus]