Senior Unreal Engine / Multiplayer Engineer (Founding-Team Interest, Equity Only)

Compensation: 0.75% – 0.75%

Founding-Team Interest — Equity-Based Opportunity. i.Wonder Laboratories is currently identifying prospective founding-team members. Cash salaries have not yet been established. These listings are expressions of interest in future positions, not offers to begin unpaid employment. Any work arrangement will require a legally compliant agreement.

Senior Unreal Engine / Multiplayer Engineer at i.Wonder Laboratories: founding-team interest opportunity

Make a persistent, editable Unreal Engine world hold together while several people and their AI agents change it at the same time, and let anyone who drops reconnect without losing their work.

About i.Wonder. i.Wonder Laboratories, Inc. is an early-stage company building two connected products. Julius is a compound AI agent that runs missions across three tiers: a Prompt Architect, a Coding Agent and an Independent Reviewer. All three tiers share Project Brain, a durable mission memory. Wonderland is a persistent multiplayer open world for AI creation, built in Unreal Engine, where people and their AI agents create, collaborate and build software together. Both are in active development. What we describe here is their intended design, not a report of finished features.

What you'll own

• Wonderland's multiplayer architecture in Unreal Engine 5 (C++): session lifecycle (create, join, leave, reconnect, late-join), shared world state, and the authority rules for who may see and change what.
• Replication and synchronization of gameplay and creation state: what replicates, how often, under whose authority, and how conflicts resolve.
• Reconnection that resynchronizes a returning client without corrupting shared state or disrupting other players.
• Integrating AI agents and companions into the world as participants that act on shared projects alongside people.
• Performance budgets for CPU, GPU, memory and bandwidth, measured with repeatable benchmarks.
• Multiplayer tooling: multi-client test setups, network emulation for latency and packet loss, logging, and desync reproduction as automated tests.
• The boundary between in-engine session state and durable server-side account and project data, owned jointly with the backend engineer.

What success looks like

• Two or more players reliably create, join, leave and rejoin a shared session, and shared state stays consistent.
• Disconnects recover cleanly.
• Performance is tracked against agreed budgets.
• Every multiplayer bug is reproduced in an automated multi-client test before it is fixed.

You have

• Professional multiplayer experience in Unreal Engine (UE4/UE5) with C++.
• Deep knowledge of Unreal networking: replication, RPCs, relevancy, ownership and authority, prediction and reconciliation.
• You have designed session lifecycle, including join, leave and reconnection.
• Profiling with Unreal Insights, the network profiler or platform profilers.
• Methodical debugging of race conditions, desyncs and state corruption.
• You work independently in a very small team and write clearly.

Nice to have (none of these are required)

• Iris, Replication Graph, or dedicated-server deployment.
• Epic Online Services or Steamworks sessions and identity.
• Shipped UGC, building or persistent-world systems.
• Automated multi-client tests and CI for game builds.
• Interest in AI agents inside games.

Compensation and terms Equity: Proposed equity: 0.75%, four-year vesting with a one-year cliff (proposed terms, subject to final written agreements).

Cash: Cash salaries have not yet been established (see the disclosure above). No salary is offered or implied.

Type / location / visa: Founding-Team Interest · Remote (United States) · visa sponsorship is not available. Future team members are expected to make a serious time commitment once employment arrangements are finalized.

How to express interest. Apply here on Wellfound. You'll need a résumé, links to your work, and short answers to a few questions. A person reads every application. More about i.Wonder: iwonderlabs.com