diff --git a/NEWS.md b/NEWS.md
index b241582..041eaad 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,9 +1,13 @@
 # coro (development version)
 
+* Fixed a leak that occurred via JIT caching (#36).
+
+
 # coro 1.0.1
 
 * `collect()` now preserves lists and data frames (#32).
 
+
 # coro 1.0.0
 
 This is the first public version of coro.
diff --git a/R/generator.R b/R/generator.R
index 6b3a900..4fc8924 100644
--- a/R/generator.R
+++ b/R/generator.R
@@ -145,6 +145,10 @@ generator0 <- function(fn, type = "generator") {
       env <- new_generator_env(env, info)
       user_env <- env$user_env
 
+      # The compiler caches function bodies, so inline a weak
+      # reference to avoid leaks (#36)
+      weak_env <- new_weakref(env)
+
       # Forward arguments inside the user space of the state machine
       lapply(names(fmls), function(arg) env_bind_arg(user_env, arg, frame = generator_env))
 
@@ -190,7 +194,7 @@ generator0 <- function(fn, type = "generator") {
         # environment.
         env$jumped <- TRUE
         out <- evalq(envir = user_env,
-          base::evalq(envir = !!env, {
+          base::evalq(envir = rlang::wref_key(!!weak_env), {
             env_poke_exits(user_env, exits)
             !!state_machine
           })