diff --git a/.gitignore b/.gitignore
index 7182eec..9b9aaf0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,6 +5,7 @@ GRPATH
 
 # ctags
 TAGS
+tags*
 
 # binaries
 print_ast
diff --git a/token.go b/ast/token.go
similarity index 88%
rename from token.go
rename to ast/token.go
index 42f42fa..a8d993b 100644
--- a/token.go
+++ b/ast/token.go
@@ -15,25 +15,25 @@
  *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-package shs;
+package ast;
 
 import (
     "unicode"
 )
 
-type token_t int
+type Token_t int
 const (
-    LIST      token_t = iota
-    STRING    token_t = iota
-    NUMBER    token_t = iota
-    SYMBOL    token_t = iota
+    LIST      Token_t = iota
+    STRING    Token_t = iota
+    NUMBER    Token_t = iota
+    SYMBOL    Token_t = iota
 )
 
 type Token struct {
-    next *Token
-    tag token_t
-    position int
-    _inner interface{}
+    Next *Token
+    Tag Token_t
+    Position int
+    Inner interface{}
 }
 
 const string_delims string = "\"'`"
@@ -54,28 +54,28 @@ func Lex(input string) *Token {
         }
 
         *iter = new(Token)
-        (*iter).position = pos
+        (*iter).Position = pos
 
         if is_list {
-            (*iter)._inner = Lex(tok)
-            (*iter).tag = LIST
+            (*iter).Inner = Lex(tok)
+            (*iter).Tag = LIST
             is_list = false
 
         } else {
-            (*iter)._inner = tok
+            (*iter).Inner = tok
             if is_str {
-                (*iter).tag = STRING
+                (*iter).Tag = STRING
                 is_str = false
 
             } else if tokenIsNumber(tok) {
-                (*iter).tag = NUMBER
+                (*iter).Tag = NUMBER
 
             } else {
-                (*iter).tag = SYMBOL
+                (*iter).Tag = SYMBOL
             }
         }
 
-        iter = &(*iter).next
+        iter = &(*iter).Next
     }
 
     // returns -1 on unmatched string delim
diff --git a/var_table.go b/ast/var_table.go
similarity index 99%
rename from var_table.go
rename to ast/var_table.go
index af79539..bb51603 100644
--- a/var_table.go
+++ b/ast/var_table.go
@@ -15,7 +15,7 @@
  *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-package shs
+package ast
 
 type VarTable map[string]*Token
 
diff --git a/cmd/print_ast.go b/cmd/print_ast.go
index 44089a8..58c6f73 100644
--- a/cmd/print_ast.go
+++ b/cmd/print_ast.go
@@ -20,9 +20,10 @@ package main
 import (
     "strings"
     "os"
-    "git.callpipe.com/aidan/shs"
+    "git.callpipe.com/aidan/shs/io"
+    "git.callpipe.com/aidan/shs/ast"
 )
 
 func main() {
-    shs.PrintSExpression(shs.Lex(strings.Join(os.Args[1:], " ")))
+    io.PrintSExpression(ast.Lex(strings.Join(os.Args[1:], " ")))
 }
diff --git a/stack.go b/datatypes/stack.go
similarity index 85%
rename from stack.go
rename to datatypes/stack.go
index 5c05c91..9f8d724 100644
--- a/stack.go
+++ b/datatypes/stack.go
@@ -15,19 +15,23 @@
  *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-package shs
+package datatypes
+
+import (
+    "git.callpipe.com/aidan/shs/ast"
+)
 
 type TokenStack struct {
-    buffer []*Token
+    buffer []*ast.Token
     capacity int
 }
 
-func (s *TokenStack) Push(v *Token) {
+func (s *TokenStack) Push(v *ast.Token) {
     s.capacity++
     s.buffer = append(s.buffer, v)
 }
 
-func (s *TokenStack) Pop() *Token {
+func (s *TokenStack) Pop() *ast.Token {
     if s.capacity <= 0 {
         return nil
     }
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..b28dc53
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module git.callpipe.com/aidan/shs
+
+go 1.14
diff --git a/debug.go b/io/debug.go
similarity index 69%
rename from debug.go
rename to io/debug.go
index 8c2ea9e..13ba2e1 100644
--- a/debug.go
+++ b/io/debug.go
@@ -15,48 +15,50 @@
  *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-package shs
+package io
 
 import (
     "strings"
     "fmt"
+    "git.callpipe.com/aidan/shs/ast"
+    "git.callpipe.com/aidan/shs/datatypes"
 )
 
-func FmtToken(arg *Token) string {
+func FmtToken(arg *ast.Token) string {
     suffix := "->"
-    if arg.next == nil {
+    if arg.Next == nil {
         suffix = ""
     }
 
-    switch arg.tag {
-    case LIST:
+    switch arg.Tag {
+    case ast.LIST:
         return fmt.Sprintf("(%s, [List])%s", "LIST", suffix)
 
     default:
-        return fmt.Sprintf("(%s, %s)%s", GetTagAsStr(arg.tag), arg._inner, suffix)
+        return fmt.Sprintf("(%s, %s)%s", GetTagAsStr(arg.Tag), arg.Inner, suffix)
     }
 }
 
-func GetTagAsStr(tag token_t) string {
+func GetTagAsStr(tag ast.Token_t) string {
     switch tag {
-    case LIST:
+    case ast.LIST:
         return "LIST"
-    case STRING:
+    case ast.STRING:
         return "STRING"
-    case NUMBER:
+    case ast.NUMBER:
         return "NUMBER"
-    case SYMBOL:
+    case ast.SYMBOL:
         return "SYMBOL"
     }
     return "UNKNOWN"
 }
 
-func PrintSExpression(arg *Token) {
+func PrintSExpression(arg *ast.Token) {
     if arg == nil {
         return //TODO: Handle error here?
     }
 
-    var lists TokenStack;
+    var lists datatypes.TokenStack;
     lists.Push(arg)
 
 loop:
@@ -66,9 +68,9 @@ loop:
         return
     }
 
-    for iter := i; iter != nil; iter = iter.next {
-        if iter.tag == LIST {
-            lists.Push(iter._inner.(*Token))
+    for iter := i; iter != nil; iter = iter.Next {
+        if iter.Tag == ast.LIST {
+            lists.Push(iter.Inner.(*ast.Token))
         }
 
         constructor.WriteString(FmtToken(iter))
diff --git a/func_table.go b/stdlib/func_table.go
similarity index 86%
rename from func_table.go
rename to stdlib/func_table.go
index 587d145..e6b551d 100644
--- a/func_table.go
+++ b/stdlib/func_table.go
@@ -15,9 +15,13 @@
  *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-package shs
+package stdlib
 
-type Operation func(*Token) *Token
+import (
+    "git.callpipe.com/aidan/shs/ast"
+)
+
+type Operation func(*ast.Token) *ast.Token
 
 type Function struct {
     function Operation
@@ -32,7 +36,7 @@ var (
 )
 
 // TODO: Currently only checks arg list length
-func ParseFunction(target *Function, args *Token) bool {
+func ParseFunction(target *Function, args *ast.Token) bool {
     // HANDLE EXEC
     if target.args < 0 {
         return true
@@ -51,7 +55,7 @@ func ParseFunction(target *Function, args *Token) bool {
     return true
 }
 
-func CallFunction(target *Function, args *Token) *Token {
+func CallFunction(target *Function, args *ast.Token) *ast.Token {
     if !ParseFunction(target, args) {
         return args
     }
diff --git a/tags b/tags
deleted file mode 100644
index 814afde..0000000
--- a/tags
+++ /dev/null
@@ -1,38 +0,0 @@
-!_TAG_FILE_FORMAT	2	/extended format; --format=1 will not append ;" to lines/
-!_TAG_FILE_SORTED	1	/0=unsorted, 1=sorted, 2=foldcase/
-!_TAG_PROGRAM_AUTHOR	Darren Hiebert	/dhiebert@users.sourceforge.net/
-!_TAG_PROGRAM_NAME	Exuberant Ctags	//
-!_TAG_PROGRAM_URL	http://ctags.sourceforge.net	/official site/
-!_TAG_PROGRAM_VERSION	Development	//
-CallFunction	func_table.go	/^func CallFunction(target *Function, args *Token) *Token {$/;"	f
-FmtToken	debug.go	/^func FmtToken(arg *Token) string {$/;"	f
-FuncTable	func_table.go	/^type FuncTable map[string]*Function$/;"	t
-Function	func_table.go	/^type Function struct {$/;"	t
-GetFunction	func_table.go	/^func GetFunction(arg string) *Function {$/;"	f
-GetTagAsStr	debug.go	/^func GetTagAsStr(tag token_t) string {$/;"	f
-GetVar	var_table.go	/^func GetVar(arg string, library []VarTable) *Token {$/;"	f
-GlobalFuncTable	func_table.go	/^    GlobalFuncTable *FuncTable$/;"	v
-GlobalVarTable	var_table.go	/^    GlobalVarTable *VarTable$/;"	v
-LIST	token.go	/^    LIST      token_t = iota$/;"	c
-Lex	token.go	/^func Lex(input string) *Token {$/;"	f
-NUMBER	token.go	/^    NUMBER    token_t = iota$/;"	c
-Operation	func_table.go	/^type Operation func(*Token) *Token$/;"	t
-ParseFunction	func_table.go	/^func ParseFunction(target *Function, args *Token) bool {$/;"	f
-Pop	stack.go	/^func (s *TokenStack) Pop() *Token {$/;"	f
-PrintSExpression	debug.go	/^func PrintSExpression(arg *Token) {$/;"	f
-Push	stack.go	/^func (s *TokenStack) Push(v *Token) {$/;"	f
-STRING	token.go	/^    STRING    token_t = iota$/;"	c
-SYMBOL	token.go	/^    SYMBOL    token_t = iota$/;"	c
-Token	token.go	/^type Token struct {$/;"	t
-TokenStack	stack.go	/^type TokenStack struct {$/;"	t
-VarTable	var_table.go	/^type VarTable map[string]*Token$/;"	t
-main	cmd/print_ast.go	/^func main() {$/;"	f
-main	cmd/print_ast.go	/^package main$/;"	p
-shs	debug.go	/^package shs$/;"	p
-shs	func_table.go	/^package shs$/;"	p
-shs	stack.go	/^package shs$/;"	p
-shs	token.go	/^package shs;$/;"	p
-shs	var_table.go	/^package shs$/;"	p
-string_delims	token.go	/^const string_delims string = "\\"'`"$/;"	c
-tokenIsNumber	token.go	/^func tokenIsNumber(arg string) bool {$/;"	f
-token_t	token.go	/^type token_t int$/;"	t