Life & fun · alternatives · 2026
24 alternatives to Cap'n Proto, by the ex-maintainer of Protocol Buffers
Cap'n Proto is a data serialization format and RPC system created by the former maintainer of Protocol Buffers. It enables efficient communication and storage of structured data with minimal overhead. The system is… Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Cap'n Proto, by the ex-maintainer of Protocol Buffers launched in 2013; newer entries below may have overtaken it.
- 1
API for the Commelec Smart Grid control platform. Contribute to niekbouman/commelec-api development by creating an account on GitHub.
2015 · github.com · its alternatives →
- 2
If you work in C++, and you would like 2+ programs to share data structures (and/or native I/O handles a.k.a. FDs) among each other, there is a good chance Flow-IPC - will make it considerably less annoying to code than typical approaches; and - may massively reduce the latency involved. Those sharing Cap'n Proto-encoded data may have particular interest. Cap'n Proto (https://capnproto.org) is fantastic at its core task - in-place serialization with zero-copy - and we wanted to make the IPC (inter-process communication) involving capnp-serialized messages be zero-copy,…
2024 · github.com · its alternatives →
- 3
Proto.io▲135Fast, fully-interactive, high-fidelity mobile prototypes
2014 · proto.io · its alternatives →
- 4
protoCURL is cURL for Protobuf: The command-line tool for interacting with Protobuf over HTTP REST endpoints using human-readable text formats - qaware/protocurl
2023 · github.com · its alternatives →
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Atomic.io 2.0▲328Ultra fast, scalable and fully collaborative prototyping
2016 · atomic.io · its alternatives →
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Network protocol emulator and testing tool
2017 · vprotostack.com · its alternatives →
- 7
Horizon 1.0▲312Realtime, open-source backend for JavaScript apps
2016 · sequence.xyz · its alternatives →
- 8
Last week Cloudflare released Cap'n Web [1], a schema-free capability-based RPC protocol. I built capn-rs this week - a Rust implementation with full wire protocol compatibility. Links: GitHub: https://github.com/currentspace/capn-rs Crates: https://crates.io/crates/capnweb-server API docs: https://docs.rs/capnweb-server What's working: Wire compatibility verified via integration tests against TypeScript reference Multi-transport: HTTP batch, WebSocket, WebTransport (HTTP/3) Complete IL (intermediate language) expression evaluator…
2025 · github.com · its alternatives →
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ProtoPie 4.0▲378Change the way you prototype on macOS & Windows
2019 · protopie.io · its alternatives →
- 10
protocapsule▲84Helping teams iterate and share experiences
2021 · protocapsule.com · its alternatives →
- 11
Your wireframe should be easy to share with any developer on your team. Design fast with iPhone and iPad collaboration. Precursor is productive prototyping.
2015 · precursorapp.com · its alternatives →
- 12PP
2022 · pbkit.dev · its alternatives →
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- 15AP
2013 · protocoin.readthedocs.org · its alternatives →
- 16
React Proto▲313React application design and prototyping tool
2018 · react-proto.github.io · its alternatives →
- 17
ProtoPie 3.9▲285Easiest prototyping tool. More powerful than ever.
2018 · protopie.io · its alternatives →
- 18
Why I built Skir: https://medium.com/@gepheum/i-spent-15-years-with-protobuf-t... Quick start: npx skir init All the config lives in one YML file. Website: https://skir.build GitHub: https://github.com/gepheum/skir Would love feedback especially from teams running mixed-language stacks.
Mar 2026 · skir.build · its alternatives →
- 19
Proto Client▲57Read proto files and send gRPC requests though an easy GUI
2022 · apps.apple.com · its alternatives →
- 20
A Google Protocol Buffers (Protobuf) payload decoder/analyzer - sandermvanvliet/ProtobufDecoder
2021 · github.com · its alternatives →
- 21
Proto Actor - Ultra fast distributed actors for Go, C# and Java/Kotlin - asynkron/protoactor-go
2016 · github.com · its alternatives →
- 22
"interesting" VM in C. Let's see how this goes. Contribute to tekknolagi/carp development by creating an account on GitHub.
2014 · github.com · its alternatives →
- 23
Scalable open source pub/sub SDK with support for RPC, JWT authentication and Kubernetes — optimized for async/await
2016 · socketcluster.io · its alternatives →
- 24
Over the last few years, I've needed an easy way to quickly serialise and deserialise various network protocols safely and efficiently. Most of the libraries that existed at the time were either quite heavy, had less than stellar performance, or were an abstraction level above what I was looking for. I decided to put together my own class to do the job, starting with an easy, low-overhead way to move bytes in and out of arbitrary buffers. Along the way, it picked up useful bits and pieces, such as buffer structures and allocators that made the byte shuffling faster, often being able to do it…
2025 · github.com · its alternatives →
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Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →