HRTBs with associated Types

I currently try to implement a IOC-Container, where I try to build scopes entirely on the stack. To do so, a trait resolves dependencies by calling a lambda on service-request. Here is some sample code which works:

pub trait Resolvable{
    type Result;
    fn resolve(container: &Container, callback: &dyn Fn(&Self::Result));

impl Resolvable for () {
    type Result = ();
    fn resolve(_: &Container, callback: &dyn Fn(&Self::Result)) {
        let a = ();

Unfortunately, I run into problems when the type-Parameter requires a lifetime. I got inspired by Lukas Kalbertodt to use Type-Constructors. My implementation looks as follows:

trait FamilyLt<'a> {
    type Out;

struct SingleStructFamily<T: ?Sized>(PhantomData<T>);

impl<'a, T: 'a + ?Sized> FamilyLt<'a> for SingleStructFamily<T> {
    type Out = (&'a T,);

When i try to use it, it doesn't compile, but I can't see what I'm doing wrong:

trait Thing {
    type Result: for<'a> FamilyLt<'a>;
    fn resolve<TFn>(&self, c: TFn) where for<'a> TFn: Fn(<Self::Result as FamilyLt<'a>>::Out);
struct Foo();

impl Thing for Foo {
    type Result = SingleStructFamily<i32>;
    fn resolve<TFn>(&self, c: TFn) where for<'a> TFn: Fn(<Self::Result as FamilyLt<'a>>::Out) {
        let cant_be_static = 42;
        //(c)((&42,);    // Doesnt compile !

When I change the signature from as FamilyLt<'a> to as FamilyLt<'static> it at least compiles with the static reference to 42. Any suggestions how I can do someting like that (Prefferaby even without complicated "Family-Types". The generic trait-parameters/lifetimes can be changed. I'd even use unsafe code to fake a lifetime, because I know, that the reference must be valid just during the callback-invocation.

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