Ark.jl is an archetype-based Entity Component System (ECS) for Julia. It is a port of the Go ECS Ark.
——Features
- Designed for performance and highly optimized.
- Well-documented, type-stable API.
- Entity relationships as a first-class feature.
- Storage mode per component for ergonomics and SIMD.
- Extensible event system with filtering and custom event types.
- Fast batch operations for mass manipulation.
- No systems. Just queries. Use your own structure.
- Minimal dependencies, 100% test coverage.
Why ECS?
Entity Component Systems (ECS) offer a clean, scalable way to build individual- and agent-based models by separating agent data from behavioral logic. Agents are simply collections of components, while systems define how those components interact, making simulations modular, extensible, and efficient even with millions of heterogeneous individuals.
Ark.jl brings this architecture to Julia with a lightweight, performance-focused implementation that empowers scientific modellers to design complex and performant simulations without the need for deep software engineering expertise.
Manual Outline
- Quickstart
- The World
- Entities
- Components
- Queries
- Systems
- Resources
- Entity relationships
- Batch operations
- Event system
- Architecture
API Outline
API Index
Ark.zero_entityArk.EntitiesArk.EntityArk.EventRegistryArk.EventRegistryArk.EventTypeArk.FilterArk.FilterArk.GPUStructArrayArk.GPUVectorArk.ObserverArk.QueryArk.QueryArk.QueryArk.RelationshipArk.StorageArk.StructArrayArk.WorldArk.WorldArk.add_components!Ark.add_resource!Ark.close!Ark.copy_entity!Ark.count_entitiesArk.emit_event!Ark.exchange_components!Ark.get_componentsArk.get_relationsArk.get_resourceArk.has_componentsArk.has_resourceArk.is_aliveArk.is_lockedArk.is_zeroArk.new_entities!Ark.new_entity!Ark.new_event_type!Ark.observe!Ark.remove_components!Ark.remove_entities!Ark.remove_entity!Ark.remove_resource!Ark.reset!Ark.set_components!Ark.set_relations!Ark.set_resource!Ark.shuffle_entities!Ark.unpackArk.unregister!Base.lengthArk.@uncheckedArk.@unpack
Reproducibility
The documentation of Ark.jl was built using these direct dependencies,
Status `~/work/Ark.jl/Ark.jl/docs/Project.toml`
[56664e29] Ark v0.3.2 `~/work/Ark.jl/Ark.jl`
[e30172f5] Documenter v1.16.1
[d6f4376e] Markdown v1.11.0and using this machine and Julia version.
Julia Version 1.12.5
Commit 5fe89b8ddc1 (2026-02-09 16:05 UTC)
Build Info:
Official https://julialang.org release
Platform Info:
OS: Linux (x86_64-linux-gnu)
CPU: 4 × AMD EPYC 7763 64-Core Processor
WORD_SIZE: 64
LLVM: libLLVM-18.1.7 (ORCJIT, znver3)
GC: Built with stock GC
Threads: 1 default, 1 interactive, 1 GC (on 4 virtual cores)A more complete overview of all dependencies and their versions is also provided.
Status `~/work/Ark.jl/Ark.jl/docs/Manifest.toml`
[a4c015fc] ANSIColoredPrinters v0.0.1
[1520ce14] AbstractTrees v0.4.5
[7d9f7c33] Accessors v0.1.43
[56664e29] Ark v0.3.2 `~/work/Ark.jl/Ark.jl`
[944b1d66] CodecZlib v0.7.8
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[187b0558] ConstructionBase v1.6.0
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[90137ffa] StaticArrays v1.9.16
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[f43a241f] Downloads v1.7.0
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[76f85450] LibGit2 v1.11.0
[8f399da3] Libdl v1.11.0
[37e2e46d] LinearAlgebra v1.12.0
[56ddb016] Logging v1.11.0
[d6f4376e] Markdown v1.11.0
[ca575930] NetworkOptions v1.3.0
[44cfe95a] Pkg v1.12.1
[de0858da] Printf v1.11.0
[3fa0cd96] REPL v1.11.0
[9a3f8284] Random v1.11.0
[ea8e919c] SHA v0.7.0
[9e88b42a] Serialization v1.11.0
[6462fe0b] Sockets v1.11.0
[f489334b] StyledStrings v1.11.0
[fa267f1f] TOML v1.0.3
[a4e569a6] Tar v1.10.0
[8dfed614] Test v1.11.0
[cf7118a7] UUIDs v1.11.0
[4ec0a83e] Unicode v1.11.0
[e66e0078] CompilerSupportLibraries_jll v1.3.0+1
[deac9b47] LibCURL_jll v8.15.0+0
[e37daf67] LibGit2_jll v1.9.0+0
[29816b5a] LibSSH2_jll v1.11.3+1
[14a3606d] MozillaCACerts_jll v2025.11.4
[4536629a] OpenBLAS_jll v0.3.29+0
[458c3c95] OpenSSL_jll v3.5.4+0
[efcefdf7] PCRE2_jll v10.44.0+1
[83775a58] Zlib_jll v1.3.1+2
[8e850b90] libblastrampoline_jll v5.15.0+0
[8e850ede] nghttp2_jll v1.64.0+1
[3f19e933] p7zip_jll v17.7.0+0You can also download the manifest file and the project file.
Cite as
Lange, M. & Meligrana, A. (2025): Ark.jl – An archetype-based Entity Component System for Julia. DOI: 10.5281/zenodo.17512271, GitHub repository: https://github.com/ark-ecs/Ark.jl