# ldionne/dyno

Runtime polymorphism done right

Repository: https://github.com/ldionne/dyno
Canonical: https://ross.abutalabs.com/products/dyno
Language: C++
License: BSL-1.0
License Family: other
Topics: cpp, hana, cpp14, cpp11, type-erasure, polymorphism, cpp17
Last push: 2021-05-27T20:03:40+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 3548, "days_push": 1924, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1043, forks 45 (observed 2026-08-28T04:03:21.000472+00:00)

## What it is
Dyno is a C++17 header-only library for runtime polymorphism via type erasure, allowing non-intrusive interface definitions without inheritance or heap allocation. It provides fully customizable storage and virtual dispatch strategies, inspired by Rust trait objects and Go interfaces.

## Use cases
- replace virtual inheritance with type-erased interfaces
- store polymorphic objects with value semantics
- customize vtable and storage layout for polymorphic types
- implement non-intrusive interfaces for third-party types
- avoid heap allocation for dynamic dispatch
- define Rust-style trait objects in C++

## When to choose
- you need runtime polymorphism without inheritance hierarchies
- you want control over how polymorphic objects are stored and dispatched
- you're on C++17 and want value-semantics-friendly dynamic dispatch
- you need to make unrelated types fulfill a common interface non-intrusively

## When to avoid
- you need a stable, production-hardened library (it's explicitly experimental)
- you're stuck on pre-C++17 compilers
- plain virtual functions are sufficient for your use case
- you need long-term maintenance and support guarantees

## Facets
- artifact type: library
- maturity: experimental
- function: serialization
- domain: programming-languages, developer-tools
- platform: cpp, cross-platform
- tags: type-erasure, runtime-polymorphism, cpp17, header-only, value-semantics

## Member repositories
- ldionne/dyno (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:03:21.000472+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T07:02:30.506691+00:00, confidence not recorded.
  - readme: https://github.com/ldionne/dyno (fetched 2026-08-28T04:03:21.000472+00:00, sha 7494e68df64c)
- Data as of 2026-08-30T08:39:29.467469+00:00.