diff --git a/.gitattributes b/.gitattributes
new file mode 100644
index 0000000..83e0e17
--- /dev/null
+++ b/.gitattributes
@@ -0,0 +1 @@
+input linguist-vendored=true
diff --git a/2015/day-01/input b/2015/day-01/input
new file mode 100644
index 0000000..f1311c4
--- /dev/null
+++ b/2015/day-01/input
@@ -0,0 +1 @@
+()()(()()()(()()((()((()))((()((((()()((((()))()((((())(((((((()(((((((((()(((())(()()(()((()()(()(())(()((((()((()()()((((())((((((()(()(((()())(()((((()))())(())(()(()()))))))))((((((((((((()())()())())(())))(((()()()((((()(((()(()(()()(()(()()(()(((((((())(())(())())))((()())()((((()()((()))(((()()()())))(())))((((())(((()())(())(()))(()((((()())))())((()(())(((()((((()((()(())())))((()))()()(()(()))))((((((((()())((((()()((((()(()())(((((()(()())()))())(((()))()(()(()(()((((()(())(()))(((((()()(()()()(()(((())())(((()()(()()))(((()()(((())())(()(())())()()(())()()()((()(((()(())((()()((())()))((()()))((()()())((((()(()()(()(((()))()(()))))((()(((()()()))(()(((())()(()((()())(()(()()(()())(())()(((()(()())()((((()((()))))())()))((()()()()(())()())()()()((((()))))(()(((()()(((((((())()))()((((()((())()(()())(())()))(()(()())(((((((())))(((()))())))))()))())((())(()()((())()())()))))()((()()())(())((())((((()())())()()()(((()))())))()()))())(()()()(()((((((()()))())()))()(((()(((())((((()()()(()))())()()))))())()))())((())()())(((((())())((())())))(((())(((())(((((()(((((())(()(()())())(()(())(()))(()((((()))())()))))())))((()(()))))())))(((((())()))())()))))()))))(((()))()))))((()))((()((()(()(())()())))(()()()(())()))()((((())))))))(())(()((()()))(()))(()))(()((()))))))()()((((()()))()())()))))))()()()))(()((())(()))((()()()())()(((()((((())())))()((((()(()))))))())))()()())()))(()))))(()())()))))))((())))))))())()))()((())())))(()((()))()))(())))))(()))()())()()))((()(()))()()()()))))())()()))())(())()()))()))((()))))()()(()())))))()()()))((((()))()))))(()(())))(()())))((())())(()))()))))()())))()())()())))))))))()()))))())))((())((()))))())))(((()())))))))(()))()()))(()))()))))()())))))())((((()())))))))())))()()))))))))()))()))))()))))))(())))))))))())))))))))))))))())())((())))))))))()))((())))()))))))))())()(()))))))())))))()()()())()(()()()(()())(()))()()()(()())))())())))()))))())))))))()()()()())(())())()())()))))(()()()()()))))()))())())))((()())()())))()))()))))(()())))()))))))))(((()))()()))))))))))))))))))))(()))(()((()))())))())(()))(()(()(())))))()(()))()))()()))))))))))))()((()())(())())()(())))))())()())((()()))))(()()))))())()(())()))))))))))))))))))))()))(()(()())))))))()()((()))()))))))((())))()))))))))((()))())()()))())()()))((()))())))))))))))(()())()))(())((()(()()))(()())(())))()())(()(())()()))))()))()(()))))))(()))))))))))(()))())))))))))())))))())))(())))))()))))(())())))))))))()(()))))()())))())(()))()())))))))))))))())()()))))()))))))())))))()))))(())(()()()()((())()))())(()))((())()))())())(())(()()))))()))(())()()((())(())))(())))()))())))))))))()(((((())())))(())()))))(())))((()))()(((((((()))))()()))(())))))()(()))))(()()))()))())))))))(()())()))))))))())))(()))())()))(())()((())())()())())(()(()))))()))))))((()())(())()()(()())))()()))(())(())(()))())))()))(()))()()))((((()))))()))((()()()))))()))()))())))(()))()))))(())))()))())()(()))()())))())))))))())))())))()()))))))(()))())())))()))()()())())))))))))))))())))()))(()()))))())))())()(())))())))))))))))))))))()()())())))))()()()((()(()))()()(())()())()))()))))()()()))))))((()))))))))()(()(()((((((()()((()())))))))))))()))())))))((())())(()))())))())))))())()()())(())))())))()())())(())))))))()()(())))()))())))())())())()))))))))()))(()()()())())())))(())())))))))()()())()))))())))())()(())())))))))()())()))(()()(())())))()(()((()()((()()(((((())(()())()))(())()))(())))(())))))))()))()))((()))()))()))))))))()))))))))((()()())(()))(((()))(())))()))((())(((())))()())))())))))((())))))(())())((((((())())()(()))()(()((()())))((())()(()(()))))(())(()()())(())))())((()(((())())))(((()())())))())()(())())((((()()))))())((()))()()()()(())(((((((()()()((()))())(()())))(())())((((()()(()))))()((())))((())()))()(((()))())))()))((()(()))(())(()((((())((((()()(()()))(((())(()))))((((()(()))(())))))((()))(()))((()(((()(()))(()(()((()(())(()(()(()(()()((()))())(((())(()(()))))(()))()()))(())))(())()(((())(()))()((((()()))))())(()))))((())()((((()(((()))())())(((()))()())((())(())())(())()(())()(()()((((((()()))))()()(((()()))))()())()(((()(()))(()(()())(()(()))))(((((()(((())())))))(((((()((()()((())())((((((()(())(()()((()()()()()()()(()()))()(((()))()))(((((((())(((()((()())()((((())(((()(())))()((()(()()()((())((()())()))()))())))())((((((()))(()(()()()))(()((()(()(()))()((()(((()()()((())(((((())()(()))())())((()(())))(()(()())(())((())())())(((()()()(())))))())(()))))))()))))))())((()()()))((()((((((()))(((()((((()()()(((()))())()(()()(((()((()()()()())()()))()()()(()(())((()))))(()))())))))))()(()()(((((())()(()(((((()((()(()()())(()((((((((()((((((())()((((()()()((()((()((((((()))((())))))))())()))((()(()))()(()()(()((())((()()((((((((((((()())(()()()))((((()((((((())(()))())(()()((()()))()(((((((()((()()((((((()(((())))((())))((((((((()()(((((((())(((((()())(((())((())()((((()(((((((()(()(((()((((((()(((()(((((((((((()()((()()(()))((()()(((()(((())))((((())()(()(((())()(()(((())(((((((((((()))())))((((((())((()()((((()())())(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diff --git a/2015/day-01/lib.fs b/2015/day-01/lib.fs
new file mode 100644
index 0000000..31fb9ab
--- /dev/null
+++ b/2015/day-01/lib.fs
@@ -0,0 +1,40 @@
+: parse-instructions ( ulen addr  -- )
+    0 >r
+    0 u+do
+        c@+
+        dup 40 = if
+            r> r> r>
+            1 +
+            >r >r >r
+        then
+        41 = if
+            r> r> r>
+            1 -
+            >r >r >r
+        then
+    loop
+    drop
+    r>
+;
+
+256 Constant max-line
+Create line-buffer max-line 2 + allot
+0 Value fd-in
+
+: open-input ( addr u -- )
+    r/o open-file throw to fd-in
+;
+
+: close-input ( -- )
+    fd-in close-file throw
+;
+
+: parse-file ( -- u )
+    0
+    begin
+        line-buffer max-line fd-in read-line throw
+    while
+            line-buffer swap parse-instructions +
+    repeat
+    drop
+;
diff --git a/2015/day-01/main.fs b/2015/day-01/main.fs
deleted file mode 100755
index d196542..0000000
--- a/2015/day-01/main.fs
+++ /dev/null
@@ -1,56 +0,0 @@
-#! /usr/bin/env gforth
-
-: parse-instructions ( ulen addr  -- )
-    0 >r
-    0 u+do
-        c@+
-        dup 40 = if
-            r> r> r>
-            1 +
-            >r >r >r
-        then
-        41 = if
-            r> r> r>
-            1 -
-            >r >r >r
-        then
-    loop
-    r> ;
-
-s" (())"
-parse-instructions
-." return: " . cr drop
-
-s" ()()"
-parse-instructions
-." return: " . cr drop
-
-s" ((("
-parse-instructions
-." return: " . cr drop
-
-s" (()(()("
-parse-instructions
-." return: " . cr drop
-
-s" ))((((("
-parse-instructions
-." return: " . cr drop
-
-s" ())"
-parse-instructions
-." return: " . cr drop
-
-s" ))("
-parse-instructions
-." return: " . cr drop
-
-s" )))"
-parse-instructions
-." return: " . cr drop
-
-s" )())())"
-parse-instructions
-." return: " . cr drop
-
-bye
diff --git a/2015/day-01/stage-1.fs b/2015/day-01/stage-1.fs
new file mode 100755
index 0000000..f8ec6e5
--- /dev/null
+++ b/2015/day-01/stage-1.fs
@@ -0,0 +1,9 @@
+#! /usr/bin/env gforth
+
+require lib.fs
+
+s" input" open-input
+parse-file . cr
+close-input
+
+bye
diff --git a/2015/day-01/test.fs b/2015/day-01/test.fs
new file mode 100755
index 0000000..c5f2a3e
--- /dev/null
+++ b/2015/day-01/test.fs
@@ -0,0 +1,18 @@
+#! /usr/bin/env gforth
+
+require lib.fs
+require ../../lib/tap.fs
+
+8 plan
+
+s" (())" parse-instructions 0 = ok
+s" ()()" parse-instructions 0 = ok
+s" (((" parse-instructions 3 = ok
+s" (()(()(" parse-instructions 3 = ok
+s" ))(((((" parse-instructions 3 = ok
+s" ())" parse-instructions -1 = ok
+s" ))(" parse-instructions -1 = ok
+s" )))" parse-instructions -3 = ok
+s" )())())" parse-instructions -3 = ok
+
+bye
diff --git a/lib/tap.fs b/lib/tap.fs
new file mode 100644
index 0000000..0d4f70a
--- /dev/null
+++ b/lib/tap.fs
@@ -0,0 +1,12 @@
+Variable test#
+
+: plan ( n -- )
+    ." 1.." . cr
+;
+
+: ok ( f -- )
+    0= if ." not " then
+    ." ok "
+    test# dup @ 1+ dup . swap !
+    cr
+;