diff --git a/Cargo.toml b/Cargo.toml
index 25f9445..d804dbc 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -11,6 +11,7 @@ hyper = "0.11.15"
 hyper-tls = "0.1.2"
 lazy_static = "1.0.0"
 maud = "0.17.2"
+ordermap = "0.4.0"
 route-recognizer = "0.1.12"
 semver = { version = "0.9.0", features = ["serde"] }
 serde = "1.0.27"
diff --git a/src/engine/machines/crawler.rs b/src/engine/machines/crawler.rs
index 1f9492e..9a4b875 100644
--- a/src/engine/machines/crawler.rs
+++ b/src/engine/machines/crawler.rs
@@ -2,12 +2,13 @@ use std::collections::HashMap;
 use std::path::PathBuf;
 
 use failure::Error;
+use ordermap::map::OrderMap;
 
 use ::parsers::manifest::parse_manifest_toml;
 use ::models::crates::{CrateDeps, CrateName, CrateManifest};
 
 pub struct ManifestCrawlerOutput {
-    pub crates: Vec<(CrateName, CrateDeps)>
+    pub crates: OrderMap<CrateName, CrateDeps>
 }
 
 pub struct ManifestCrawlerStepOutput {
@@ -16,14 +17,14 @@ pub struct ManifestCrawlerStepOutput {
 
 pub struct ManifestCrawler {
     manifests: HashMap<PathBuf, CrateManifest>,
-    leaf_crates: Vec<(CrateName, CrateDeps)>
+    leaf_crates: OrderMap<CrateName, CrateDeps>
 }
 
 impl ManifestCrawler {
     pub fn new() -> ManifestCrawler {
         ManifestCrawler {
             manifests: HashMap::new(),
-            leaf_crates: vec![]
+            leaf_crates: OrderMap::new()
         }
     }
 
@@ -37,7 +38,7 @@ impl ManifestCrawler {
 
         match manifest {
             CrateManifest::Package(name, deps) => {
-                self.leaf_crates.push((name, deps));
+                self.leaf_crates.insert(name, deps);
             },
             CrateManifest::Workspace { members } => {
                 for mut member in members {
@@ -45,7 +46,7 @@ impl ManifestCrawler {
                 }
             },
             CrateManifest::Mixed { name, deps, members } => {
-                self.leaf_crates.push((name, deps));
+                self.leaf_crates.insert(name, deps);
                 for mut member in members {
                     output.paths_of_interest.push(path.clone().join(member));
                 }
diff --git a/src/main.rs b/src/main.rs
index 9436b32..4176812 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -10,6 +10,7 @@ extern crate hyper;
 extern crate hyper_tls;
 #[macro_use] extern crate lazy_static;
 extern crate maud;
+extern crate ordermap;
 extern crate route_recognizer;
 extern crate semver;
 #[macro_use] extern crate serde_derive;
diff --git a/src/models/crates.rs b/src/models/crates.rs
index 78ef916..5f8827a 100644
--- a/src/models/crates.rs
+++ b/src/models/crates.rs
@@ -6,7 +6,7 @@ use std::str::FromStr;
 use failure::Error;
 use semver::{Version, VersionReq};
 
-#[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]
+#[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct CrateName(String);
 
 impl Into<String> for CrateName {