diff --git a/crates/prometeu-compiler/src/analysis/types.rs b/crates/prometeu-compiler/src/analysis/types.rs
index 73a1eca2..1b7ef4f4 100644
--- a/crates/prometeu-compiler/src/analysis/types.rs
+++ b/crates/prometeu-compiler/src/analysis/types.rs
@@ -1,4 +1,5 @@
 use crate::analysis::symbols::SymbolId;
+use crate::frontends::pbs::ast::NodeId;
 use prometeu_analysis::interner::NameId;
 use serde::{Deserialize, Serialize};
 
@@ -37,6 +38,42 @@ impl TypeArena {
     }
 }
 
+#[derive(Debug, Default, Serialize, Deserialize)]
+pub struct TypeFacts {
+    pub node_type: Vec<Option<TypeId>>,
+    pub symbol_type: Vec<Option<TypeId>>,
+}
+
+impl TypeFacts {
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    pub fn set_node_type(&mut self, node_id: NodeId, type_id: TypeId) {
+        let idx = node_id.0 as usize;
+        if idx >= self.node_type.len() {
+            self.node_type.resize_with(idx + 1, || None);
+        }
+        self.node_type[idx] = Some(type_id);
+    }
+
+    pub fn get_node_type(&self, node_id: NodeId) -> Option<TypeId> {
+        self.node_type.get(node_id.0 as usize).and_then(|t| *t)
+    }
+
+    pub fn set_symbol_type(&mut self, symbol_id: SymbolId, type_id: TypeId) {
+        let idx = symbol_id.0 as usize;
+        if idx >= self.symbol_type.len() {
+            self.symbol_type.resize_with(idx + 1, || None);
+        }
+        self.symbol_type[idx] = Some(type_id);
+    }
+
+    pub fn get_symbol_type(&self, symbol_id: SymbolId) -> Option<TypeId> {
+        self.symbol_type.get(symbol_id.0 as usize).and_then(|t| *t)
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -71,4 +108,28 @@ mod tests {
         assert!(matches!(arena.kind(t2), TypeKind::Optional { .. }));
         assert!(matches!(arena.kind(t3), TypeKind::Array { .. }));
     }
+
+    #[test]
+    fn type_facts_auto_grows_for_node_ids() {
+        let mut facts = TypeFacts::new();
+        let nid = NodeId(10);
+        let tid = TypeId(1);
+        
+        assert_eq!(facts.get_node_type(nid), None);
+        facts.set_node_type(nid, tid);
+        assert_eq!(facts.get_node_type(nid), Some(tid));
+        assert!(facts.node_type.len() > 10);
+    }
+
+    #[test]
+    fn type_facts_auto_grows_for_symbol_ids() {
+        let mut facts = TypeFacts::new();
+        let sid = SymbolId(20);
+        let tid = TypeId(2);
+        
+        assert_eq!(facts.get_symbol_type(sid), None);
+        facts.set_symbol_type(sid, tid);
+        assert_eq!(facts.get_symbol_type(sid), Some(tid));
+        assert!(facts.symbol_type.len() > 20);
+    }
 }