diff --git a/.gitignore b/.gitignore
index 4c9e245..1078bf3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -21,3 +21,5 @@ cabal.project.local
 cabal.project.local~
 .HTF/
 .ghc.environment.*
+a.out
+a.out.ll
\ No newline at end of file
diff --git a/.vscode/extensions.json b/.vscode/extensions.json
new file mode 100644
index 0000000..2201e47
--- /dev/null
+++ b/.vscode/extensions.json
@@ -0,0 +1,7 @@
+{
+    "recommendations": [
+        "gattytto.phoityne-vscode",
+        "haskell.haskell",
+        "justusadam.language-haskell"
+    ]
+}
\ No newline at end of file
diff --git a/.vscode/launch.json b/.vscode/launch.json
new file mode 100644
index 0000000..ad9207c
--- /dev/null
+++ b/.vscode/launch.json
@@ -0,0 +1,46 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "type": "ghc",
+            "request": "launch",
+            "name": "haskell(stack)",
+            "internalConsoleOptions": "openOnSessionStart",
+            "workspace": "${workspaceFolder}",
+            "startup": "${workspaceFolder}/test/Spec.hs",
+            "startupFunc": "",
+            "startupArgs": "",
+            "stopOnEntry": false,
+            "mainArgs": "",
+            "ghciPrompt": "H>>= ",
+            "ghciInitialPrompt": "Prelude>",
+            "ghciCmd": "stack ghci --test --no-load --no-build --main-is TARGET",
+            "ghciEnv": {},
+            "logFile": "${workspaceFolder}/.vscode/phoityne.log",
+            "logLevel": "WARNING",
+            "forceInspect": false
+        },
+        {
+            "type": "ghc",
+            "request": "launch",
+            "name": "haskell(cabal)",
+            "internalConsoleOptions": "openOnSessionStart",
+            "workspace": "${workspaceFolder}",
+            "startup": "${workspaceFolder}/Main.hs",
+            "startupFunc": "",
+            "startupArgs": "",
+            "stopOnEntry": false,
+            "mainArgs": "",
+            "ghciPrompt": "H>>= ",
+            "ghciInitialPrompt": "Prelude>",
+            "ghciCmd": "cabal exec -- ghci-dap --interactive -i -i${workspaceFolder}",
+            "ghciEnv": {},
+            "logFile": "${workspaceFolder}/.vscode/phoityne.log",
+            "logLevel": "WARNING",
+            "forceInspect": false
+        }
+    ]
+}
\ No newline at end of file
diff --git a/.vscode/tasks.json b/.vscode/tasks.json
new file mode 100644
index 0000000..c7efda6
--- /dev/null
+++ b/.vscode/tasks.json
@@ -0,0 +1,50 @@
+
+{
+  // Automatically created by phoityne-vscode extension.
+
+  "version": "2.0.0",
+  "presentation": {
+    "reveal": "always",
+    "panel": "new"
+  },
+  "tasks": [
+    {
+      // F7
+      "group": {
+        "kind": "build",
+        "isDefault": true
+      },
+      "label": "haskell build",
+      "type": "shell",
+      //"command": "cabal configure && cabal build"
+      "command": "stack build"
+    },
+    {
+      // F6
+      "group": "build",
+      "type": "shell",
+      "label": "haskell clean & build",
+      //"command": "cabal clean && cabal configure && cabal build"
+      "command": "stack clean && stack build"
+      //"command": "stack clean ; stack build"  // for powershell
+    },
+    {
+      // F8
+      "group": {
+        "kind": "test",
+        "isDefault": true
+      },
+      "type": "shell",
+      "label": "haskell test",
+      //"command": "cabal test"
+      "command": "stack test"
+    },
+    {
+      // F6
+      "isBackground": true,
+      "type": "shell",
+      "label": "haskell watch",
+      "command": "stack build --test --no-run-tests --file-watch"
+    }
+  ]
+}
diff --git a/README.md b/README.md
index f26cbc7..e6b3a8f 100644
--- a/README.md
+++ b/README.md
@@ -1,15 +1,23 @@
 # Really Bad Compiler in Haskell
 
-A compiler written in Haskell which can currently perform basic arithmetic using the megaparsec and llvm-hs libraries (I do not know what language I am going to compile yet). Built for the Introduction to Compiler Design class at The University of Texas at Dallas.
+A compiler written in Haskell which can currently perform basic arithmetic. Currently using the megaparsec and llvm-hs-\* libraries, but I may reimplement certain libraries myself. Built for the Introduction to Compiler Design class at The University of Texas at Dallas.
 
 Main repo: https://git.sudoer.ch/me/really-bad-compiler-in-haskell
 
-## Build Instructions
+## Setup Instructions
 
 - Install `ghcup` (for managing Haskell tools) and `nix` (for managing external dependencies).
 - Clone the repo.
 - Use `ghcup` to install `stack 2.9.3`, `HLS 2.2.0.0`, `GHC 9.2.8`, and `cabal 3.6.2.0`.
+
+## Run Instructions
+
 - Use `stack run <file>` to run the program (for example, `stack run example/1`).
+- The LLVM will be generated as `a.out.ll`, and the executable will be generated as `a.out`.
+
+## To edit
+
+I recommend using VSCodium, which is preconfigured to have syntax highlighting and (currently broken) debugging features and will automatically suggest the Haskell extensions to install.
 
 ## Known bugs
 
@@ -27,20 +35,23 @@ Main repo: https://git.sudoer.ch/me/really-bad-compiler-in-haskell
 ### Learning Resources Used
 
 - Introduction to Compiler Design class at The University of Texas at Dallas, taught by Charles Averill
-- learnyouahaskell.com (for learning Haskell basics)
+- https://learnyouahaskell.com (for learning Haskell basics)
 - https://akashagrawal.me/2017/01/19/beginners-guide-to-megaparsec.html
-- https://markkarpov.com/tutorial/megaparsec.html (for help writing a Haskell equation parser)
+- https://markkarpov.com/tutorial/megaparsec.html (for help writing a Haskell equation parser using megaparsec)
 - https://www.forth.com/starting-forth/1-forth-stacks-dictionary/ (for learning Forth)
 - https://blog.josephmorag.com/posts/mcc0/ (Haskell compiler tutorial with megaparsec, llvm-hs, and nix)
-- https://gh.sudoer.ch/llvm-hs/llvm-hs-examples (for help writing an llvm code generator)
+- https://gh.sudoer.ch/llvm-hs/llvm-hs-examples (for help writing an llvm code generator using llvm-hs)
+- https://danieljharvey.github.io/posts/2023-02-08-llvm-compiler-part-1.html (for help using llvm-hs-pure)
+- https://gh.sudoer.ch/danieljharvey/mimsa/blob/trunk/llvm-calc/src/Calc/Compile/ToLLVM.hs (source code for above resource)
+- https://9to5tutorial.com/homebrew-compiler-made-with-haskell-llvm-configuration (for help using llvm-hs-pure)
 
 ### Tools
 
 - Language: Haskell
-- Haskell tools: GHCup, Stack, Cabal
-- Libraries: megaparsec, parser-combinators, text, llvm-hs-pure
-- Dependencies: llvm, clang
+- Haskell tools: GHCup, Stack, Cabal, GHC 9.2
+- Libraries: megaparsec, parser-combinators, text, process, llvm-hs 15, llvm-hs-pure 15,
+- Dependencies: llvm 15, clang 15
 - IDE: VSCodium
 - Git platform: Forgejo
-- AI: Phind
+- AI: Phind (GPT-4), ollama (codellama)
 - Search: Kagi, Stack Overflow
diff --git a/app/Eval/Expression.hs b/app/Eval/Expression.hs
deleted file mode 100644
index 325afdf..0000000
--- a/app/Eval/Expression.hs
+++ /dev/null
@@ -1,13 +0,0 @@
-module Eval.Expression (evalExpr) where
-
-import Objects.Expression
-
-eval :: Expr -> Int
-eval (Lit x) = x
-eval (Add x y) = eval x + eval y
-eval (Sub x y) = eval x - eval y
-eval (Mul x y) = eval x * eval y
-eval (Div x y) = eval x `div` eval y
-
-evalExpr :: Expr -> Int
-evalExpr = eval
\ No newline at end of file
diff --git a/app/LLVMGen/Expression.hs b/app/LLVMGen/Expression.hs
deleted file mode 100644
index 0b2c4d2..0000000
--- a/app/LLVMGen/Expression.hs
+++ /dev/null
@@ -1,51 +0,0 @@
-module LLVMGen.Expression () where
-
-import qualified Objects.Expression as Expr
-
-import LLVM.AST
-import qualified LLVM.AST as AST
-import LLVM.AST.Global
-import LLVM.Context
-import LLVM.Module
-
-import Data.ByteString.Char8 as BS
-
-int :: Type
-int = IntegerType 32
-
-defAdd :: Definition
-defAdd = GlobalDefinition functionDefaults
-  { name = Name "add"
-  , parameters =
-      ( [ Parameter int (Name "a") []
-        , Parameter int (Name "b") [] ]
-      , False )
-  , returnType = int
-  , basicBlocks = [body]
-  }
-  where
-    body = BasicBlock
-        (Name "entry")
-        [ Name "result" :=
-            Add False  -- no signed wrap
-                False  -- no unsigned wrap
-                (LocalReference int (Name "a"))
-                (LocalReference int (Name "b"))
-                []]
-        (Do $ Ret (Just (LocalReference int (Name "result"))) [])
-
-
-module_ :: AST.Module
-module_ = defaultModule
-  { moduleName = "basic"
-  , moduleDefinitions = [defAdd]
-  }
-
-
-toLLVM :: AST.Module -> IO ()
-toLLVM modul = withContext $ \ctx -> do
-  llvm <- withModuleFromAST ctx modul moduleLLVMAssembly
-  BS.putStrLn llvm
-
-main :: IO ()
-main = toLLVM module_
\ No newline at end of file
diff --git a/app/Main.hs b/app/Main.hs
deleted file mode 100644
index d9407df..0000000
--- a/app/Main.hs
+++ /dev/null
@@ -1,22 +0,0 @@
-module Main (main) where
-
-import Control.Monad
-import Data.Either
-import Eval.Expression
-import Objects.Expression
-import Parser.Expression
-import System.Environment
-import System.IO
-import Text.Megaparsec
-
-getRight :: ParseResult -> Expr
-getRight (Right r) = r
-
-getResult :: String -> Int
-getResult str = evalExpr (getRight (parseExpr str))
-
-main = do
-  fileName <- fmap head getArgs
-  contents <- readFile fileName
-  let result = getResult contents
-  print result
diff --git a/app/Objects/Expression.hs b/app/Objects/Expression.hs
deleted file mode 100644
index 932df82..0000000
--- a/app/Objects/Expression.hs
+++ /dev/null
@@ -1,19 +0,0 @@
-module Objects.Expression
-  ( Expr
-      ( Lit,
-        Add,
-        Sub,
-        Mul,
-        Div
-      ),
-      -- solve,
-  )
-where
-
-data Expr
-  = Lit Int
-  | Add Expr Expr
-  | Sub Expr Expr
-  | Mul Expr Expr
-  | Div Expr Expr
-  deriving (Show)
\ No newline at end of file
diff --git a/main/Compiler/LLVMGen.hs b/main/Compiler/LLVMGen.hs
new file mode 100644
index 0000000..d36277d
--- /dev/null
+++ b/main/Compiler/LLVMGen.hs
@@ -0,0 +1,67 @@
+{-# LANGUAGE ImportQualifiedPost #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE RecursiveDo #-}
+
+-- see https://gh.sudoer.ch/danieljharvey/mimsa/blob/trunk/llvm-calc/src/Calc/Compile/ToLLVM.hs
+
+module Compiler.LLVMGen (llvmGen) where
+
+-- import LLVM.Pretty
+
+import Data.ByteString (ByteString)
+import Debug.Trace
+import LLVM (moduleLLVMAssembly, withModuleFromAST, writeLLVMAssemblyToFile)
+import LLVM.AST hiding (function)
+import LLVM.AST.Type
+import LLVM.Context
+import LLVM.IRBuilder.Constant
+import LLVM.IRBuilder.Instruction
+import LLVM.IRBuilder.Module
+import LLVM.IRBuilder.Monad
+import Types.Expr as Expr
+
+getLLVM :: Expr -> Module
+getLLVM expr =
+  buildModule "program" $ mdo
+    -- TODO: better module name
+    printf <- externVarArgs "printf" [ptr] i32
+    function "main" [] i32 $ \_ -> mdo
+      numFormatStr <- globalStringPtr "%d\n" (mkName "str")
+      ourExpression <- exprToLLVM expr
+      _ <- call (FunctionType i32 [ptr] True) printf [(ConstantOperand numFormatStr, []), (ourExpression, [])]
+      ret (int32 0)
+
+exprToLLVM ::
+  ( MonadIRBuilder m,
+    MonadModuleBuilder m
+  ) =>
+  Expr ->
+  m Operand
+exprToLLVM (Lit prim) = pure $ primToLLVM prim
+exprToLLVM (Expr.Add a b) = mdo
+  lhs <- exprToLLVM a
+  rhs <- exprToLLVM b
+  add lhs rhs
+exprToLLVM (Expr.Sub a b) = mdo
+  lhs <- exprToLLVM a
+  rhs <- exprToLLVM b
+  sub lhs rhs
+exprToLLVM (Expr.Mul a b) = mdo
+  lhs <- exprToLLVM a
+  rhs <- exprToLLVM b
+  mul lhs rhs
+exprToLLVM (Expr.Div a b) = mdo
+  lhs <- exprToLLVM a
+  rhs <- exprToLLVM b
+  sdiv lhs rhs
+
+primToLLVM :: Int -> Operand
+primToLLVM i = int32 (fromIntegral i)
+
+llvmGen :: Expr -> IO ByteString
+llvmGen expr = do
+  let l = getLLVM expr
+  withContext
+    ( \c ->
+        withModuleFromAST c l moduleLLVMAssembly
+    )
\ No newline at end of file
diff --git a/main/Main.hs b/main/Main.hs
new file mode 100644
index 0000000..dda57c6
--- /dev/null
+++ b/main/Main.hs
@@ -0,0 +1,28 @@
+{-# LANGUAGE ImportQualifiedPost #-}
+{-# LANGUAGE OverloadedStrings #-}
+
+module Main (main) where
+
+-- import Compiler.ExeGen
+import Compiler.LLVMGen
+import Data.ByteString.Char8 qualified as B
+import Data.Text.Lazy.IO qualified as T
+import Parser.Expr
+import System.Environment
+import System.Process
+import Types.Expr
+
+getRight :: ParseResult -> Expr
+getRight (Right r) = r
+
+main :: IO ()
+main = do
+  fileName <- fmap head getArgs
+  contents <- readFile fileName
+  T.putStrLn "- Parsing file..."
+  let parsed = getRight (parseExpr contents)
+  T.putStrLn "- Generating LLVM to './a.out.ll'..."
+  llvmGen parsed >>= B.writeFile "a.out.ll"
+  T.putStrLn "- Compiling to executable './a.out'..."
+  callCommand "clang a.out.ll"
+  T.putStrLn "- Done."
diff --git a/app/Parser/Expression.hs b/main/Parser/Expr.hs
similarity index 72%
rename from app/Parser/Expression.hs
rename to main/Parser/Expr.hs
index 0d323ff..a2f3f4c 100644
--- a/app/Parser/Expression.hs
+++ b/main/Parser/Expr.hs
@@ -1,11 +1,15 @@
-module Parser.Expression (parseExpr, ParseResult) where
+-- see https://markkarpov.com/tutorial/megaparsec.html
+{-# LANGUAGE ImportQualifiedPost #-}
+
+module Parser.Expr (parseExpr, ParseResult) where
 
 import Control.Monad.Combinators.Expr
+import Data.Functor.Identity qualified
 import Data.Void (Void)
-import Objects.Expression
 import Text.Megaparsec as MP
 import Text.Megaparsec.Char as C
 import Text.Megaparsec.Char.Lexer as L
+import Types.Expr
 
 type Parser = Parsec Void String
 
@@ -31,6 +35,7 @@ table =
     ]
   ]
 
+binaryOp :: String -> (a -> a -> a) -> Operator (ParsecT Void String Data.Functor.Identity.Identity) a
 binaryOp name f = InfixL (f <$ symbolParser name)
 
 expr :: Parser Expr
diff --git a/main/Types/Expr.hs b/main/Types/Expr.hs
new file mode 100644
index 0000000..51c8925
--- /dev/null
+++ b/main/Types/Expr.hs
@@ -0,0 +1,11 @@
+module Types.Expr (Expr (..)) where
+
+data Expr
+  = Lit Int
+  | Add Expr Expr
+  | Sub Expr Expr
+  | Mul Expr Expr
+  | Div Expr Expr
+  deriving
+    ( Show
+    )
\ No newline at end of file
diff --git a/package.yaml b/package.yaml
index af19751..99c82b0 100644
--- a/package.yaml
+++ b/package.yaml
@@ -6,9 +6,9 @@ dependencies:
   - megaparsec >= 9.0.1 && < 10
   - parser-combinators
   - text
+  - process
   - llvm-hs >= 15 && < 16
   - llvm-hs-pure >= 15 && < 16
-  # - llvm-hs-pretty >= 15 && < 16
   - bytestring
 tested-with: GHC == 9.2.8
 category: Compilers/Interpreters
@@ -19,7 +19,7 @@ ghc-options: -threaded -Wall -j8 +RTS -A64M -RTS -fllvm
 #   source-dirs: src
 
 executable:
-  source-dirs: app
+  source-dirs: main
   main: Main.hs
 # tests:
 #   testall:
diff --git a/really-bad-compiler-in-haskell.cabal b/really-bad-compiler-in-haskell.cabal
index 25ecb34..d82f626 100644
--- a/really-bad-compiler-in-haskell.cabal
+++ b/really-bad-compiler-in-haskell.cabal
@@ -16,13 +16,12 @@ tested-with:
 executable really-bad-compiler-in-haskell
   main-is: Main.hs
   other-modules:
-      Eval.Expression
-      LLVMGen.Expression
-      Objects.Expression
-      Parser.Expression
+      Compiler.LLVMGen
+      Parser.Expr
+      Types.Expr
       Paths_really_bad_compiler_in_haskell
   hs-source-dirs:
-      app
+      main
   default-extensions:
       OverloadedStrings, LambdaCase
   ghc-options: -threaded -Wall -j8 +RTS -A64M -RTS -fllvm
@@ -33,5 +32,6 @@ executable really-bad-compiler-in-haskell
     , llvm-hs-pure ==15.*
     , megaparsec >=9.0.1 && <10
     , parser-combinators
+    , process
     , text
   default-language: Haskell2010
diff --git a/stack.yaml b/stack.yaml
index f5a1103..45dc800 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -3,8 +3,6 @@ resolver: lts-20.26
 packages:
   - .
 extra-deps:
-  # - github: hyunsooda/llvm-hs-pretty-15
-  #   commit: 79283942d1667168ecd65237667aff7fed730303
   - github: llvm-hs/llvm-hs
     commit: 5bca2c1a2a3aa98ecfb19181e7a5ebbf3e212b76
     subdirs: