diff --git a/Cargo.lock b/Cargo.lock
index a85fb04..19c25c1 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -393,6 +393,7 @@
  "filetime",
  "jemallocator",
  "libc",
+ "rustc-hash",
  "tempfile",
  "windows-sys 0.48.0",
 ]
@@ -532,6 +533,12 @@
 checksum = "c08c74e62047bb2de4ff487b251e4a92e24f48745648451635cec7d591162d9f"
 
 [[package]]
+name = "rustc-hash"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "08d43f7aa6b08d49f382cde6a7982047c3426db949b1424bc4b7ec9ae12c6ce2"
+
+[[package]]
 name = "rustix"
 version = "0.37.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/Cargo.toml b/Cargo.toml
index 43e21af..b91b120 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -18,6 +18,7 @@
 anyhow = "1.0"
 argh = "0.1.10"
 libc = "0.2"
+rustc-hash = "1.1.0"
 
 [target.'cfg(windows)'.dependencies.windows-sys]
 version = "0.48"
diff --git a/src/eval.rs b/src/eval.rs
index 4b711c5..d737bfe 100644
--- a/src/eval.rs
+++ b/src/eval.rs
@@ -1,10 +1,11 @@
 //! Represents parsed Ninja strings with embedded variable references, e.g.
 //! `c++ $in -o $out`, and mechanisms for expanding those into plain strings.
 
+use rustc_hash::FxHashMap;
+
 use crate::smallmap::SmallMap;
 use std::borrow::Borrow;
 use std::borrow::Cow;
-use std::collections::HashMap;
 
 /// An environment providing a mapping of variable name to variable value.
 /// This represents one "frame" of evaluation context, a given EvalString may
@@ -121,7 +122,7 @@
 
 /// A single scope's worth of variable definitions.
 #[derive(Debug, Default)]
-pub struct Vars<'text>(HashMap<&'text str, String>);
+pub struct Vars<'text>(FxHashMap<&'text str, String>);
 
 impl<'text> Vars<'text> {
     pub fn insert(&mut self, key: &'text str, val: String) {
diff --git a/src/graph.rs b/src/graph.rs
index f15c35a..d6b1a38 100644
--- a/src/graph.rs
+++ b/src/graph.rs
@@ -1,5 +1,7 @@
 //! The build graph, a graph between files and commands.
 
+use rustc_hash::FxHashMap;
+
 use crate::{
     densemap::{self, DenseMap},
     hash::BuildHash,
@@ -258,7 +260,7 @@
 #[derive(Default)]
 pub struct GraphFiles {
     pub by_id: DenseMap<FileId, File>,
-    by_name: HashMap<String, FileId>,
+    by_name: FxHashMap<String, FileId>,
 }
 
 impl Graph {