If you want to see some examples, Neon uses this pattern to solve a similar problem - preventing rust code from holding onto js objects that might get gced betw

If you want to see some examples, Neon uses this pattern to solve a similar problem - preventing rust code from holding onto js objects that might get gced between callbacks. https://github.com/neon-bindings/neon https://github.com/neon-bindings/neon