diff --git a/crates/mako/src/config.rs b/crates/mako/src/config.rs
index 79dbab66b..265c81884 100644
--- a/crates/mako/src/config.rs
+++ b/crates/mako/src/config.rs
@@ -28,7 +28,7 @@ mod tree_shaking;
 mod umd;
 mod watch;
 
-use std::collections::{BTreeMap, HashMap};
+use std::collections::HashMap;
 use std::fmt;
 use std::path::{Path, PathBuf};
 
@@ -49,6 +49,7 @@ pub use external::{
 };
 pub use generic_usize::GenericUsizeDefault;
 pub use hmr::{deserialize_hmr, HmrConfig};
+use indexmap::IndexMap;
 pub use inline_css::{deserialize_inline_css, InlineCssConfig};
 pub use manifest::{deserialize_manifest, ManifestConfig};
 use miette::{miette, ByteOffset, Diagnostic, NamedSource, SourceOffset, SourceSpan};
@@ -128,7 +129,7 @@ pub enum Platform {
 #[derive(Deserialize, Serialize, Debug)]
 #[serde(rename_all = "camelCase")]
 pub struct Config {
-    pub entry: BTreeMap<String, PathBuf>,
+    pub entry: IndexMap<String, PathBuf>,
     pub output: OutputConfig,
     pub resolve: ResolveConfig,
     #[serde(deserialize_with = "deserialize_manifest", default)]
diff --git a/crates/mako/src/module_graph.rs b/crates/mako/src/module_graph.rs
index 765a160ff..cf13db051 100644
--- a/crates/mako/src/module_graph.rs
+++ b/crates/mako/src/module_graph.rs
@@ -1,7 +1,8 @@
-use std::collections::{BTreeSet, HashMap, HashSet};
+use std::collections::{HashMap, HashSet};
 use std::fmt;
 
 use fixedbitset::FixedBitSet;
+use indexmap::IndexSet;
 use petgraph::graph::{DefaultIx, NodeIndex};
 use petgraph::prelude::{Dfs, EdgeRef};
 use petgraph::stable_graph::{StableDiGraph, WalkNeighbors};
@@ -15,7 +16,7 @@ use crate::module::{Dependencies, Dependency, Module, ModuleId};
 pub struct ModuleGraph {
     pub id_index_map: HashMap<ModuleId, NodeIndex<DefaultIx>>,
     pub graph: StableDiGraph<Module, Dependencies>,
-    entries: BTreeSet<ModuleId>,
+    entries: IndexSet<ModuleId>,
 }
 
 impl ModuleGraph {
@@ -23,7 +24,7 @@ impl ModuleGraph {
         Self {
             id_index_map: HashMap::new(),
             graph: StableDiGraph::new(),
-            entries: BTreeSet::new(),
+            entries: IndexSet::new(),
         }
     }