diff --git a/compiler/src/IR.hs b/compiler/src/IR.hs
index 55228d1..0c12310 100644
--- a/compiler/src/IR.hs
+++ b/compiler/src/IR.hs
@@ -292,6 +292,7 @@ instance WellFormedIRCheck IRExpr where
                      , "_setFailureRate"
                      , "sleep"
                      , "spawn"
+                     , "sqrt"
                      , "substring"
                      , "stringToInt"
                      , "restore"
diff --git a/rt/src/builtins/math.mts b/rt/src/builtins/math.mts
index 66b51f6..0c61535 100644
--- a/rt/src/builtins/math.mts
+++ b/rt/src/builtins/math.mts
@@ -26,5 +26,12 @@ export function BuiltinMath <TBase extends Constructor<UserRuntimeZero>> (Base:T
             assertIsNumber(arg);
             return this.runtime.ret(new LVal(Math.floor(arg.val), arg.lev, arg.tlev));
         })
+
+        sqrt = mkBase((arg) => {
+            assertIsNumber(arg);
+            return this.runtime.ret(new LVal(Math.sqrt(arg.val), arg.lev, arg.tlev));
+        })
+
+        
     }
 }
\ No newline at end of file