# Reactivity and signals: demystifying frontend magic

> Unpack frontend reactivity: change propagation, dependency tracking, signals, computed values, and effects in modern frameworks.

- Date: 2026-06-27
- Event: [Asynconf](<https://app.itsasync.fr/conference>)
- Location: Paris, France
- Topics: computed-values, dependency-tracking, effects, frontend-reactivity, signals, vue

## Resources

- [Slides](<https://talks.soubiran.dev/2026-06-27-1/asynconf>)
- [PDF](<https://talks.soubiran.dev/2026-06-27-1/asynconf/pdf>)
- [Source code](<https://talks.soubiran.dev/2026-06-27-1/asynconf/src>)

## Summary

This talk explains frontend reactivity with a small signal-based system. It starts from `ui = fn(state)`, then uses `alien-signals` to connect signals, computed values, and effects through a dependency graph.

The examples introduce directed graphs, doubly linked lists, push and pull propagation, and the implementation of reactive updates. The presentation ends by relating the model to Vue's `ReactiveEffect` and component scopes.