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+# Similar projects
+
+There are many projects similar to `EnTT`, both open source and not.<br/>
+Some even borrowed some ideas from this library and expressed them in different
+languages.<br/>
+Others developed different architectures from scratch and therefore offer
+alternative solutions with their pros and cons.
+
+Below an incomplete list of those that I've come across so far.<br/>
+If some terms or designs aren't clear, I recommend referring to the
+[_ECS Back and Forth_](https://skypjack.github.io/tags/#ecs) series for all the
+details.
+
+I hope this list can grow much more in the future:
+
+* C:
+  * [destral_ecs](https://github.com/roig/destral_ecs): a single-file ECS based
+    on sparse sets.
+  * [Diana](https://github.com/discoloda/Diana): an ECS that uses sparse sets to
+    keep track of entities in systems.
+  * [Flecs](https://github.com/SanderMertens/flecs): a multithreaded archetype
+    ECS based on semi-contiguous arrays rather than chunks.
+  * [lent](https://github.com/nem0/lent): the Donald Trump of the ECS libraries.
+
+* C++:
+  * [decs](https://github.com/vblanco20-1/decs): a chunk based archetype ECS.
+  * [ecst](https://github.com/SuperV1234/ecst): a multithreaded compile-time
+    ECS that uses sparse sets to keep track of entities in systems.
+  * [EntityX](https://github.com/alecthomas/entityx): a bitset based ECS that
+    uses a single large matrix of components indexed with entities.
+  * [Gaia-ECS](https://github.com/richardbiely/gaia-ecs): a chunk based
+    archetype ECS.
+  * [Polypropylene](https://github.com/pmbittner/Polypropylene): a hybrid
+    solution between an ECS and dynamic mixins.
+
+* C#
+  * [Entitas](https://github.com/sschmid/Entitas-CSharp): the ECS framework for
+    C# and Unity, where _reactive systems_ were invented.
+  * [LeoECS](https://github.com/Leopotam/ecs): simple lightweight C# Entity
+    Component System framework.
+  * [Svelto.ECS](https://github.com/sebas77/Svelto.ECS): a very interesting
+    platform agnostic and table based ECS framework.
+
+* Go:
+  * [gecs](https://github.com/tutumagi/gecs): a sparse sets based ECS inspired 
+    by `EnTT`.
+
+* Javascript:
+  * [\@javelin/ecs](https://github.com/3mcd/javelin/tree/master/packages/ecs):
+    an archetype ECS in TypeScript.
+  * [ecsy](https://github.com/MozillaReality/ecsy): I haven't had the time to
+    investigate the underlying design of `ecsy` but it looks cool anyway.
+
+* Perl:
+  * [Game::Entities](https://gitlab.com/jjatria/perl-game-entities): a simple
+    entity registry for ECS designs inspired by `EnTT`.
+
+* Raku:
+  * [Game::Entities](https://gitlab.com/jjatria/raku-game-entities): a simple
+    entity registry for ECS designs inspired by `EnTT`.
+
+* Rust:
+  * [Legion](https://github.com/TomGillen/legion): a chunk based archetype ECS.
+  * [Shipyard](https://github.com/leudz/shipyard): it borrows some ideas from
+    `EnTT` and offers a sparse sets based ECS with grouping functionalities.
+  * [Sparsey](https://github.com/LechintanTudor/sparsey): sparse set based ECS
+    written in Rust.
+  * [Specs](https://github.com/amethyst/specs): a parallel ECS based mainly on
+    hierarchical bitsets that allows different types of storage as needed.
+
+* Zig
+  * [zig-ecs](https://github.com/prime31/zig-ecs): a _zig-ification_ of `EnTT`.
+
+If you know of other resources out there that can be of interest for the reader,
+feel free to open an issue or a PR and I'll be glad to add them to this page.