diff --git a/Cargo.lock b/Cargo.lock
index 5cd0555..cab7774 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,12 +2,54 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "arg"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "568bbed0b9810cd4b43c8560ff3c5d2318b29d78fc314818d156bbed7075d394"
+dependencies = [
+ "arg-derive",
+]
+
+[[package]]
+name = "arg-derive"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "849efc162c06e51ce911bf4fe702f62a08f3b6ebbbfc5178e86c6bae449c2c60"
+dependencies = [
+ "quote",
+ "syn",
+ "tabwriter",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
 
+[[package]]
+name = "bindgen"
+version = "0.63.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "36d860121800b2a9a94f9b5604b332d5cffb234ce17609ea479d723dbc9d3885"
+dependencies = [
+ "bitflags",
+ "cexpr",
+ "clang-sys",
+ "lazy_static",
+ "lazycell",
+ "log",
+ "peeking_take_while",
+ "proc-macro2",
+ "quote",
+ "regex",
+ "rustc-hash",
+ "shlex",
+ "syn",
+ "which",
+]
+
 [[package]]
 name = "bitflags"
 version = "1.3.2"
@@ -18,8 +60,19 @@ checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 name = "breed"
 version = "0.1.0"
 dependencies = [
+ "arg",
  "crossterm",
  "ropey",
+ "yacexits",
+]
+
+[[package]]
+name = "cexpr"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6fac387a98bb7c37292057cffc56d62ecb629900026402633ae9160df93a8766"
+dependencies = [
+ "nom",
 ]
 
 [[package]]
@@ -28,6 +81,17 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
+[[package]]
+name = "clang-sys"
+version = "1.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c688fc74432808e3eb684cae8830a86be1d66a2bd58e1f248ed0960a590baf6f"
+dependencies = [
+ "glob",
+ "libc",
+ "libloading",
+]
+
 [[package]]
 name = "crossterm"
 version = "0.26.1"
@@ -53,12 +117,46 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "either"
+version = "1.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7fcaabb2fef8c910e7f4c7ce9f67a1283a1715879a7c230ca9d6d1ae31f16d91"
+
+[[package]]
+name = "glob"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2fabcfbdc87f4758337ca535fb41a6d701b65693ce38287d856d1674551ec9b"
+
+[[package]]
+name = "lazy_static"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
+
+[[package]]
+name = "lazycell"
+version = "1.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "830d08ce1d1d941e6b30645f1a0eb5643013d835ce3779a5fc208261dbe10f55"
+
 [[package]]
 name = "libc"
 version = "0.2.141"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3304a64d199bb964be99741b7a14d26972741915b3649639149b2479bb46f4b5"
 
+[[package]]
+name = "libloading"
+version = "0.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b67380fd3b2fbe7527a606e18729d21c6f3951633d0500574c4dc22d2d638b9f"
+dependencies = [
+ "cfg-if",
+ "winapi",
+]
+
 [[package]]
 name = "lock_api"
 version = "0.4.9"
@@ -78,6 +176,18 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "memchr"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
+
+[[package]]
+name = "minimal-lexical"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
+
 [[package]]
 name = "mio"
 version = "0.8.6"
@@ -90,6 +200,22 @@ dependencies = [
  "windows-sys",
 ]
 
+[[package]]
+name = "nom"
+version = "7.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d273983c5a657a70a3e8f2a01329822f3b8c8172b73826411a55751e404a0a4a"
+dependencies = [
+ "memchr",
+ "minimal-lexical",
+]
+
+[[package]]
+name = "once_cell"
+version = "1.17.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b7e5500299e16ebb147ae15a00a942af264cf3688f47923b8fc2cd5858f23ad3"
+
 [[package]]
 name = "parking_lot"
 version = "0.12.1"
@@ -113,6 +239,30 @@ dependencies = [
  "windows-sys",
 ]
 
+[[package]]
+name = "peeking_take_while"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "19b17cddbe7ec3f8bc800887bab5e717348c95ea2ca0b1bf0837fb964dc67099"
+
+[[package]]
+name = "proc-macro2"
+version = "1.0.56"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2b63bdb0cd06f1f4dedf69b254734f9b45af66e4a031e42a7480257d9898b435"
+dependencies = [
+ "unicode-ident",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.26"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4424af4bf778aae2051a77b60283332f386554255d722233d09fbfc7e30da2fc"
+dependencies = [
+ "proc-macro2",
+]
+
 [[package]]
 name = "redox_syscall"
 version = "0.2.16"
@@ -122,6 +272,21 @@ dependencies = [
  "bitflags",
 ]
 
+[[package]]
+name = "regex"
+version = "1.7.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b1f693b24f6ac912f4893ef08244d70b6067480d2f1a46e950c9691e6749d1d"
+dependencies = [
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.6.29"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f162c6dd7b008981e4d40210aca20b4bd0f9b60ca9271061b07f78537722f2e1"
+
 [[package]]
 name = "ropey"
 version = "1.6.0"
@@ -132,12 +297,24 @@ dependencies = [
  "str_indices",
 ]
 
+[[package]]
+name = "rustc-hash"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "08d43f7aa6b08d49f382cde6a7982047c3426db949b1424bc4b7ec9ae12c6ce2"
+
 [[package]]
 name = "scopeguard"
 version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
 
+[[package]]
+name = "shlex"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "43b2853a4d09f215c24cc5489c992ce46052d359b5109343cbafbf26bc62f8a3"
+
 [[package]]
 name = "signal-hook"
 version = "0.3.15"
@@ -180,12 +357,55 @@ version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5f026164926842ec52deb1938fae44f83dfdb82d0a5b0270c5bd5935ab74d6dd"
 
+[[package]]
+name = "syn"
+version = "1.0.109"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "72b64191b275b66ffe2469e8af2c1cfe3bafa67b529ead792a6d0160888b4237"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
+[[package]]
+name = "tabwriter"
+version = "1.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "36205cfc997faadcc4b0b87aaef3fbedafe20d38d4959a7ca6ff803564051111"
+dependencies = [
+ "unicode-width",
+]
+
+[[package]]
+name = "unicode-ident"
+version = "1.0.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e5464a87b239f13a63a501f2701565754bae92d243d4bb7eb12f6d57d2269bf4"
+
+[[package]]
+name = "unicode-width"
+version = "0.1.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c0edd1e5b14653f783770bce4a4dabb4a5108a5370a5f5d8cfe8710c361f6c8b"
+
 [[package]]
 name = "wasi"
 version = "0.11.0+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
 
+[[package]]
+name = "which"
+version = "4.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2441c784c52b289a054b7201fc93253e288f094e2f4be9058343127c4226a269"
+dependencies = [
+ "either",
+ "libc",
+ "once_cell",
+]
+
 [[package]]
 name = "winapi"
 version = "0.3.9"
@@ -273,3 +493,13 @@ name = "windows_x86_64_msvc"
 version = "0.42.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9aec5da331524158c6d1a4ac0ab1541149c0b9505fde06423b02f5ef0106b9f0"
+
+[[package]]
+name = "yacexits"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "53fe740dd05c1bbc919431e842e6c1bea30195e0518ae99cae35b7f0730ddc18"
+dependencies = [
+ "bindgen",
+ "libc",
+]
diff --git a/Cargo.toml b/Cargo.toml
index f8a2bcf..9dc3429 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -5,5 +5,7 @@ edition = "2021"
 license = "AGPL-3.0-or-later"
 
 [dependencies]
+arg = "0.4.1"
 crossterm = "0.26"
 ropey = "1.6"
+yacexits = "0.1.5"
diff --git a/src/main.rs b/src/main.rs
index 3410254..ea9a540 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2023 Marceline Cramer
+ * Copyright (c) 2023 Emma Tebibyte <emma@tebibyte.media>
  * SPDX-License-Identifier: AGPL-3.0-or-later
  *
  * This program is free software: you can redistribute it and/or modify it under
@@ -16,7 +17,17 @@
  * along with this program. If not, see https://www.gnu.org/licenses/.
  */
 
-use std::io::{stdout, Stdout, Write};
+use std::{
+    env::args,
+    fs::File,
+    io::{
+        Read,
+        stdout,
+        Stdout,
+        Write,
+    },
+    os::fd::FromRawFd,
+};
 
 use crossterm::{
     cursor,
@@ -24,6 +35,7 @@ use crossterm::{
     terminal, ExecutableCommand, Result,
 };
 use ropey::Rope;
+use yacexits::{ exit, EX_DATAERR, EX_UNAVAILABLE };
 
 struct Buffer {
     pub text: Rope,
@@ -435,8 +447,31 @@ fn screen_main(stdout: &mut Stdout, mut state: State) -> Result<()> {
 }
 
 fn main() -> Result<()> {
-    let text = include_str!("main.rs");
-    let state = State::from_str(text)?;
+    let argv = args().collect::<Vec<String>>();
+    let mut buf = Vec::new();
+
+    match argv.get(1).map(|s| s.as_str()) {
+        Some("-") | None => unsafe { File::from_raw_fd(0) }, // stdin as a file
+        Some(path) => {
+            std::fs::File::open(path).unwrap_or_else(|_| {
+                eprintln!(
+                    "{}: {}: No such file or directory.",
+                    argv[0],
+                    argv[1]
+                );
+                exit(EX_UNAVAILABLE);
+            })
+        },
+    }.read_to_end(&mut buf).unwrap();
+
+    let text = String::from_utf8(buf).unwrap_or_else(|_| {
+        eprintln!(
+            "{}: {}: File contents are not valid UTF-8.", argv[0], argv[1]
+        );
+        exit(EX_DATAERR);
+    });
+
+    let state = State::from_str(&text)?;
     let mut stdout = stdout();
     terminal::enable_raw_mode()?;
     stdout.execute(terminal::EnterAlternateScreen)?;