Bring Your Game Into a
Port a single-player or multiplayer game to add shared presence and sync selected systems, or build something entirely new in one persistent environment.
What To Consider When Porting
Share what matters. Keep what works.
Crowded Kingdoms doesn't require every object, enemy, or system to move onto CK Spatial Fabric. Add a thin connected layer, or go all the way to fully shared gameplay. The depth is up to you.
Two Paths In
Start light and expand, or make Crowded Kingdoms foundational from day one.
Best for single-player games, lightweight multiplayer additions, and gradual adoption. Keep your existing architecture: connect only the features you choose to share.
Best for persistent online worlds, dense realtime interaction, and games currently capped by shards or instances. CK Spatial Fabric becomes part of state, authority, and replication from the start — true single-shard, not sharding dressed up to look seamless.
Choose Your Depth
Each stop is a deeper integration option — start with a thin shared layer, or go all the way to a fully shared world.
Position, orientation, animation, appearance, ghost data. Enables ghost races, time trials, and nearby-player visibility, usually without touching the core gameplay loop.
Chat, emotes, parties, friend presence, hubs, leaderboards, community challenges. The game stays intact; it gains a persistent community around it.
Shared events, trading, player-built structures, resources, discoveries, or select NPCs. The core design question: who owns the authoritative version of each shared object.
Realtime combat, large NPC populations, physics-sensitive interactions, persistent world modification, shared economies. This is the deepest path: replication, authority, and persistence become part of the game architecture, and the payoff is a genuinely living world players can't get anywhere else.
Estimate Your Effort
| Feature | Typical effort |
|---|---|
| Raw player position and movement sync between clients | Lower |
| Ghost replay of your own or a top player's run | Lower |
| Nameplates and identity for nearby players, no shared gameplay | Lower |
| Proximity voice/text chat and emotes in a shared hub | Lower–Moderate |
| Friends list, parties, and cross-session leaderboards | Lower–Moderate |
| Syncing event data everyone sees: weather, day/night, event timers | Moderate |
| A rare world event (boss spawn, meteor strike) visible to every player online | Moderate |
| Player-built structures or claimed land other players can see and enter | Moderate–Substantial |
| Player-driven economy: auction house, crafting, shared resource scarcity | Moderate–Substantial |
| Realtime cooperative combat with shared hit registration and loot | Substantial |
| Converting client-authoritative combat or physics into a secure shared model | Substantial |
| One authoritative simulation — economy, NPC AI, world state — for every player, no instancing | Highest |
Not Just Multiplayer
Augment your solo experience with time trials, phantom sightings of another player's run, simultaneous speed-run competitions where everyone can see each other's runs, and anything else you can imagine.
Shared social hubs and event spaces can all be added with minimal effort too. It's a small lift that makes players feel like they're part of something alive, not just replaying the same campaign alone.
How You Build
Browser-first with CrowdyJS, native Unreal, or portable C++ for any other engine. Every path talks to the same shared world.
A typed client wrapping the Management and Game APIs with shared auth, a good fit for browser games, shared hubs, social layers, and persistent multiplayer experiences.
CrowdyJS SDKSpans Management, Game, and Replication. Bring an existing Unreal project into CK Spatial Fabric, or build new at native performance.
Unreal SDKA portable, high-performance C++ SDK that brings any non-Unreal engine or custom client onto CK Spatial Fabric — typed access to the Management, Game, and Replication APIs, with native replication for lower-latency state sync.
CrowdyCPP SDKGame Kit
Game Kit packages the systems most games need — inventory, economy, quests, combat, and more — as typed, ready-made building blocks in both CrowdyJS and CrowdyCPP. Deploy the rules once, play from either SDK. It cut thousands of lines of boilerplate from our own game.
Shared presence is one of the cheapest features to ship, and one of the best at keeping players coming back and giving them something worth telling a friend about. The first integration doesn't have to be the final architecture: start with presence, a ghost system, or a shared hub, then expand. The dev vlog covers real builds and tests as we ship them.
Watch the Dev VlogDocumentation
Full API reference and integration guides, including the porting paths and SDK docs covered on this page.
Read the DocsNew Build
Create an app and start building in the dev tier: connect via CrowdyJS, CrowdyCPP, or the Unreal SDK whenever you're ready.
Get API Access