diff --git a/flake.nix b/flake.nix
index 7cb1cfb..8f30908 100644
--- a/flake.nix
+++ b/flake.nix
@@ -50,7 +50,6 @@
     pkgs = nixpkgs.legacyPackages.${system};
     pkgs-stable = nixpkgs-stable.legacyPackages.${system};
     pkgs-unstable-small = nixpkgs-unstable-small.legacyPackages.${system};
-    crane-lib = crane.mkLib nixpkgs.legacyPackages.${system};
     rs-toolchain = with fenix.packages.${system};
       combine [
         complete.toolchain
@@ -59,6 +58,7 @@
     #   cargo = rs-toolchain;
     #   rustc = rs-toolchain;
     # };
+    crane-lib = (crane.mkLib nixpkgs.legacyPackages.${system}).overrideToolchain rs-toolchain;
     rs-programs = final: prev: {
       # s10e-jrnl = rs-platform.buildRustPackage {
       #   pname = "jrnl";
diff --git a/programs/flip-bool/src/main.rs b/programs/flip-bool/src/main.rs
index 3ae9375..299685f 100644
--- a/programs/flip-bool/src/main.rs
+++ b/programs/flip-bool/src/main.rs
@@ -1,4 +1,22 @@
-use std::io::{Read, Write};
+#![feature(iter_array_chunks)]
+#![feature(round_char_boundary)]
+#![feature(iter_collect_into)]
+#![feature(pattern)]
+
+use std::{
+    hint::black_box,
+    io::{Read, Write},
+    str::pattern::Pattern,
+};
+
+const BOOL_COUNT: usize = BOOLS.len();
+const BOOLS: &[[&str; 2]] = &[
+    ["false", "true"],
+    ["False", "True"],
+    ["FALSE", "TRUE"],
+    ["0", "1"],
+    ["no", "yes"],
+];
 
 fn main() {
     let mut input = String::new();
@@ -7,19 +25,95 @@ fn main() {
 
     stdin.read_to_string(&mut input).unwrap();
 
+    let bool_locs = find_bools(&input);
     stdout
-        .write_all(match input.as_bytes() {
-            b"true" => b"false",
-            b"True" => b"False",
-            b"TRUE" => b"FALSE",
-            b"false" => b"true",
-            b"False" => b"True",
-            b"FALSE" => b"TRUE",
-            b"1" => b"0",
-            b"yes" => b"no",
-            b"0" => b"1",
-            b"no" => b"yes",
-            other => other,
-        })
+        .write_all(replace_bools(&mut input, bool_locs).as_bytes())
         .unwrap();
 }
+
+type BoolLocs = [[Vec<usize>; 2]; BOOL_COUNT];
+
+// you thought [`find_bools`] was stupid? this is *so* much worse!!!
+fn replace_bools(input: &str, mut bool_locs: BoolLocs) -> String {
+    let mut result = String::with_capacity(input.len());
+    let mut intermediate = input;
+    let mut flattened = bool_locs
+        .iter_mut()
+        .flatten()
+        .map(|vec| {
+            vec.reverse();
+            vec
+        })
+        .enumerate()
+        .collect::<Vec<_>>();
+
+    let mut smallest = || {
+        let min_idx = flattened
+            .iter()
+            .min_by(|va, vb| {
+                va.1.last()
+                    .unwrap_or(&usize::MAX)
+                    .cmp(vb.1.last().unwrap_or(&usize::MAX))
+            })?
+            .0;
+
+        Some((min_idx, flattened[min_idx].1.pop()?))
+    };
+
+    let mut input_idx = 0;
+    while let Some(item) = smallest() {
+        let (a, b) = intermediate.split_at(item.1 - input_idx);
+        input_idx += a.len();
+        result += a;
+        let bool_ = &BOOLS[item.0 / 2];
+        input_idx += bool_[item.0 % 2].len();
+        result += bool_[if item.0 % 2 == 0 { 1 } else { 0 }];
+        let (_, b) = b.split_at(bool_[item.0 % 2].len());
+        intermediate = b;
+    }
+
+    result + intermediate
+}
+
+// this is so fucking stupid
+// it also would've been way easier using a regex crate lmao
+fn find_bools(input: &str) -> [[Vec<usize>; 2]; BOOL_COUNT] {
+    let mut res = Vec::with_capacity(BOOL_COUNT);
+    BOOLS
+        .iter()
+        .flatten()
+        .map(|it| {
+            input
+                .match_indices(it)
+                .filter_map(|it| {
+                    let char_guard = |c: char| !(c.is_alphanumeric() || c.is_contained_in("-_"));
+                    let mut allow = true;
+
+                    if it.0 > 0 {
+                        allow &= char_guard(
+                            input[it.1.floor_char_boundary(it.0 - 1)..it.0]
+                                .chars()
+                                .last()
+                                .unwrap(),
+                        );
+                    }
+
+                    let last_idx = it.0 + it.1.len();
+                    if last_idx < input.len() {
+                        allow &= char_guard(
+                            input[(last_idx)..(input.ceil_char_boundary(last_idx + 1))]
+                                .chars()
+                                .last()
+                                .unwrap(),
+                        );
+                    }
+
+                    allow.then_some(it.0)
+                })
+                .collect()
+        })
+        .array_chunks::<2>()
+        .collect_into(&mut res);
+
+    res.try_into().unwrap()
+}