diff --git a/crates/glue/src/RocType.roc b/crates/glue/src/RocType.roc
index ee0e00e136..9c97e382dd 100644
--- a/crates/glue/src/RocType.roc
+++ b/crates/glue/src/RocType.roc
@@ -44,6 +44,10 @@ TypeId : Nat
 # isEqTypeId = \@TypeId lhs, @TypeId rhs -> lhs == rhs
 # hashTypeId = \hasher, @TypeId id -> Hash.hash hasher id
 
+# TODO: switch AssocList uses to Dict once roc_std is updated.
+Tuple1 : [ T Str TypeId ]
+Tuple2 : [ T TypeId (List TypeId) ]
+
 Types : {
     # These are all indexed by TypeId
     types: List RocType,
@@ -51,12 +55,12 @@ Types : {
     aligns: List U32,
 
     # Needed to check for duplicates
-    typesByName: Dict Str TypeId,
+    typesByName: List Tuple1,
 
     ## Dependencies - that is, which type depends on which other type.
     ## This is important for declaration order in C; we need to output a
     ## type declaration earlier in the file than where it gets referenced by another type.
-    deps: Dict TypeId (List TypeId),
+    deps: List Tuple2,
     target: Target,
 }
 
diff --git a/crates/glue/src/roc_type/mod.rs b/crates/glue/src/roc_type/mod.rs
index f6e55508d9..20e8a5fbf3 100644
--- a/crates/glue/src/roc_type/mod.rs
+++ b/crates/glue/src/roc_type/mod.rs
@@ -32,20 +32,35 @@ pub struct File {
 
 #[cfg(any(
     target_arch = "arm",
+    target_arch = "aarch64",
     target_arch = "wasm32",
-    target_arch = "x86"
+    target_arch = "x86",
+    target_arch = "x86_64"
 ))]
 #[derive(Clone, Debug, Eq, Ord, Hash, PartialEq, PartialOrd)]
 #[repr(C)]
 pub struct Types {
     pub aligns: roc_std::RocList<u32>,
-    pub deps: roc_std::RocDict<u32, roc_std::RocList<u32>>,
+    pub deps: roc_std::RocList<Tuple2>,
     pub sizes: roc_std::RocList<u32>,
     pub types: roc_std::RocList<RocType>,
-    pub typesByName: roc_std::RocDict<roc_std::RocStr, u32>,
+    pub typesByName: roc_std::RocList<Tuple1>,
     pub target: Target,
 }
 
+#[cfg(any(
+    target_arch = "arm",
+    target_arch = "wasm32",
+    target_arch = "x86"
+))]
+#[repr(C)]
+#[derive(Clone, Default, Eq, Ord, Hash, PartialEq, PartialOrd)]
+pub struct Tuple1 {
+    f0: roc_std::RocStr,
+    f1: u32,
+}
+
+
 #[cfg(any(
     target_arch = "arm",
     target_arch = "aarch64",
@@ -154,6 +169,19 @@ pub struct R3 {
     pub r#type: u32,
 }
 
+#[cfg(any(
+    target_arch = "arm",
+    target_arch = "wasm32",
+    target_arch = "x86"
+))]
+#[repr(C)]
+#[derive(Clone, Default, Eq, Ord, Hash, PartialEq, PartialOrd)]
+pub struct Tuple2 {
+    f0: u32,
+    f1: roc_std::RocList<u32>,
+}
+
+
 #[cfg(any(
     target_arch = "arm",
     target_arch = "aarch64",
@@ -516,17 +544,14 @@ pub struct R1 {
     target_arch = "aarch64",
     target_arch = "x86_64"
 ))]
-#[derive(Clone, Debug, Eq, Ord, Hash, PartialEq, PartialOrd)]
-#[repr(C)]
-pub struct Types {
-    pub aligns: roc_std::RocList<u32>,
-    pub deps: roc_std::RocDict<u64, roc_std::RocList<u64>>,
-    pub sizes: roc_std::RocList<u32>,
-    pub types: roc_std::RocList<RocType>,
-    pub typesByName: roc_std::RocDict<roc_std::RocStr, u64>,
-    pub target: Target,
+#[repr(transparent)]
+#[derive(Clone, Default, Eq, Ord, Hash, PartialEq, PartialOrd)]
+pub struct Tuple1 {
+    f0: roc_std::RocStr,
+    f1: u64,
 }
 
+
 #[cfg(any(
     target_arch = "aarch64",
     target_arch = "x86_64"
@@ -569,6 +594,18 @@ pub struct R3 {
     pub r#type: u64,
 }
 
+#[cfg(any(
+    target_arch = "aarch64",
+    target_arch = "x86_64"
+))]
+#[repr(transparent)]
+#[derive(Clone, Default, Eq, Ord, Hash, PartialEq, PartialOrd)]
+pub struct Tuple2 {
+    f0: u64,
+    f1: roc_std::RocList<u64>,
+}
+
+
 #[cfg(any(
     target_arch = "aarch64",
     target_arch = "x86_64"
@@ -695,6 +732,88 @@ pub struct R1 {
     pub ret: u64,
 }
 
+impl Tuple1 {
+    #[cfg(any(
+        target_arch = "arm",
+        target_arch = "wasm32",
+        target_arch = "x86"
+    ))]
+    /// A tag named T, with the given payload.
+    pub fn T(f0: roc_std::RocStr, f1: u32) -> Self {
+        Self {
+            f0,
+            f1,
+        }
+    }
+
+    #[cfg(any(
+        target_arch = "arm",
+        target_arch = "wasm32",
+        target_arch = "x86"
+    ))]
+    /// Since `T` only has one tag (namely, `T`),
+    /// convert it to `T`'s payload.
+    pub fn into_T(self) -> (roc_std::RocStr, u32) {
+        (self.f0, self.f1)
+    }
+
+    #[cfg(any(
+        target_arch = "arm",
+        target_arch = "wasm32",
+        target_arch = "x86"
+    ))]
+    /// Since `T` only has one tag (namely, `T`),
+    /// convert it to `T`'s payload.
+    pub fn as_T(&self) -> (&roc_std::RocStr, &u32) {
+        (&self.f0, &self.f1)
+    }
+
+    #[cfg(any(
+        target_arch = "aarch64",
+        target_arch = "x86_64"
+    ))]
+    /// A tag named T, with the given payload.
+    pub fn T(f0: roc_std::RocStr, f1: u64) -> Self {
+        Self {
+            f0,
+            f1,
+        }
+    }
+
+    #[cfg(any(
+        target_arch = "aarch64",
+        target_arch = "x86_64"
+    ))]
+    /// Since `T` only has one tag (namely, `T`),
+    /// convert it to `T`'s payload.
+    pub fn into_T(self) -> (roc_std::RocStr, u64) {
+        (self.f0, self.f1)
+    }
+
+    #[cfg(any(
+        target_arch = "aarch64",
+        target_arch = "x86_64"
+    ))]
+    /// Since `T` only has one tag (namely, `T`),
+    /// convert it to `T`'s payload.
+    pub fn as_T(&self) -> (&roc_std::RocStr, &u64) {
+        (&self.f0, &self.f1)
+    }
+}
+
+impl core::fmt::Debug for Tuple1 {
+    #[cfg(any(
+        target_arch = "arm",
+        target_arch = "aarch64",
+        target_arch = "wasm32",
+        target_arch = "x86",
+        target_arch = "x86_64"
+    ))]
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
+            f.debug_tuple("Tuple1::T")                .field(&self.f0)                .field(&self.f1)                .finish()    }
+
+}
+
 impl RocType {
     #[cfg(any(
         target_arch = "arm",
@@ -2175,6 +2294,88 @@ impl core::fmt::Debug for RocType {
     }
 }
 
+impl Tuple2 {
+    #[cfg(any(
+        target_arch = "arm",
+        target_arch = "wasm32",
+        target_arch = "x86"
+    ))]
+    /// A tag named T, with the given payload.
+    pub fn T(f0: u32, f1: roc_std::RocList<u32>) -> Self {
+        Self {
+            f0,
+            f1,
+        }
+    }
+
+    #[cfg(any(
+        target_arch = "arm",
+        target_arch = "wasm32",
+        target_arch = "x86"
+    ))]
+    /// Since `T` only has one tag (namely, `T`),
+    /// convert it to `T`'s payload.
+    pub fn into_T(self) -> (u32, roc_std::RocList<u32>) {
+        (self.f0, self.f1)
+    }
+
+    #[cfg(any(
+        target_arch = "arm",
+        target_arch = "wasm32",
+        target_arch = "x86"
+    ))]
+    /// Since `T` only has one tag (namely, `T`),
+    /// convert it to `T`'s payload.
+    pub fn as_T(&self) -> (&u32, &roc_std::RocList<u32>) {
+        (&self.f0, &self.f1)
+    }
+
+    #[cfg(any(
+        target_arch = "aarch64",
+        target_arch = "x86_64"
+    ))]
+    /// A tag named T, with the given payload.
+    pub fn T(f0: u64, f1: roc_std::RocList<u64>) -> Self {
+        Self {
+            f0,
+            f1,
+        }
+    }
+
+    #[cfg(any(
+        target_arch = "aarch64",
+        target_arch = "x86_64"
+    ))]
+    /// Since `T` only has one tag (namely, `T`),
+    /// convert it to `T`'s payload.
+    pub fn into_T(self) -> (u64, roc_std::RocList<u64>) {
+        (self.f0, self.f1)
+    }
+
+    #[cfg(any(
+        target_arch = "aarch64",
+        target_arch = "x86_64"
+    ))]
+    /// Since `T` only has one tag (namely, `T`),
+    /// convert it to `T`'s payload.
+    pub fn as_T(&self) -> (&u64, &roc_std::RocList<u64>) {
+        (&self.f0, &self.f1)
+    }
+}
+
+impl core::fmt::Debug for Tuple2 {
+    #[cfg(any(
+        target_arch = "arm",
+        target_arch = "aarch64",
+        target_arch = "wasm32",
+        target_arch = "x86",
+        target_arch = "x86_64"
+    ))]
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
+            f.debug_tuple("Tuple2::T")                .field(&self.f0)                .field(&self.f1)                .finish()    }
+
+}
+
 impl RocTagUnion {
     #[cfg(any(
         target_arch = "arm",