dustingetz / krestianstvo-electric

Krestianstvo | Electric - Clojure. Implementing a scalable Croquet VM.

Krestianstvo | Electric Clojure. Implementing a scalable Croquet VM.

Work In Progress

This repository contains the implementation of the Croquet VM (based on Krestianstvo SDK 4 and Virtual World Framework) in Electric Clojure programming language.

The big idea here is to use the Electric distributed runtime as a basis for a higher level scene graph sync abstraction for use in collaborative virtual worlds.

Here are the first steps video with a <200 LoC classic Croquet VM implementation from Krestianstvo SDK 4:

20230508.Nikolai.Electric.Krestianstvo.mp4

• In <200 LoC all parts of the classic Croquet VM are implemented, including Reflector server, Virtual Time, Recursive Future Messages etc. VM is distributed in a single Electric application as a DAG.
• Krestianstvo in Electric makes Croquet VM being scalable. Meaning, that previous single Reflector server can be scaled up across networks organising the fleet of Reflectors.
• Internal dispatcher of the Croquet VM messages queue can be distributed across hardware threads safely.
• Krestianstvo applications can be potentially run not only in web-browsers, but also in any Clojure hosted environment, scaling horizontally & vertically.

Demo prototype is running at: https://e.krestianstvo.org

Learn more about Krestianstvo SDK 4 here: https://play.krestianstvo.org

Background

Croquet is a software development kit (SDK) for use in developing collaborative virtual world applications. The Croquet software architecture is known for its radical synchronization system with the notion of virtual time.

• What is Croquet Anyways
• https://en.wikipedia.org/wiki/Croquet_Project
• https://en.wikipedia.org/wiki/Croquet_OS
• https://croquet.io/croquet-os/

Krestianstvo SDK 4 is the Open Source implementation of the Croquet application architecture in Functional Reactive Paradigm.

• https://github.com/NikolaySuslov/krestianstvo
• https://www.krestianstvo.org/
• https://docs.krestianstvo.org/en/introduction/
• https://www.krestianstvo.org/docs/about/publications/

Electric Clojure is a new web development paradigm that uses a compiler to build frontend/backend network sync directly into the programming language itself.

• Electric Clojure

The Virtual World Framework (VWF) is a means to connect robust 3D, immersive, entities with other entities, virtual worlds, content and users via web browsers.

• https://github.com/virtual-world-framework/vwf
• https://en.wikipedia.org/wiki/Virtual_world_framework

Development

$ clj -A:dev -X user/main

Starting Electric compiler and server...
shadow-cljs - server version: 2.20.1 running at http://localhost:9630
shadow-cljs - nREPL server started on port 9001
[:app] Configuring build.
[:app] Compiling ...
[:app] Build completed. (224 files, 0 compiled, 0 warnings, 1.93s)

👉 App server available at http://0.0.0.0:8080

Deployment

ClojureScript optimized build, Dockerfile, Uberjar, Github actions CD to fly.io

HYPERFIDDLE_ELECTRIC_APP_VERSION=`git describe --tags --long --always --dirty`
clojure -X:build build-client          # optimized release build
clojure -X:build uberjar :jar-name "app.jar" :version '"'$HYPERFIDDLE_ELECTRIC_APP_VERSION'"'
java -DHYPERFIDDLE_ELECTRIC_SERVER_VERSION=$HYPERFIDDLE_ELECTRIC_APP_VERSION -jar app.jar

docker build --progress=plain --build-arg VERSION="$HYPERFIDDLE_ELECTRIC_APP_VERSION" -t electric-starter-app .
docker run --rm -p 7070:8080 electric-starter-app

# flyctl launch ... ? create fly app, generate fly.toml, see dashboard
# https://fly.io/apps/electric-starter-app

NO_COLOR=1 flyctl deploy --build-arg VERSION="$HYPERFIDDLE_ELECTRIC_APP_VERSION"
# https://electric-starter-app.fly.dev/

• NO_COLOR=1 disables docker-cli fancy shell GUI, so that we see the full log (not paginated) in case of exception
• --build-only tests the build on fly.io without deploying

Contributing

All code is published under the MIT license