Setup

Prerequisites

Before configuring the plugin, make sure you have:

1. An Epic Developer Portal account — dev.epicgames.com
2. A Product created in the portal with at least one Deployment
3. At least one Stat configured under Dev Portal → [Your Product] → Stats
4. At least one Leaderboard configured under Dev Portal → [Your Product] → Leaderboards, linked to that stat

Don't forget to set your ClientPolicy to one that includes Stats and Leaderboards permissions in the Dev Portal → Clients settings.

Step 1 — Enable the Plugin

In Unreal Engine:

1. Open Edit → Plugins
2. Search for EOS Leaderboard
3. Enable the plugin and restart the Editor

Step 2 — Get Your EOS Credentials

In the Epic Developer Portal, navigate to:

Your Product → Product Settings → SDK Credentials

Collect the following values:

Step 3 — Configure DefaultEngine.ini

Add the [EOSCore] section to your project's Config/DefaultEngine.ini:

[EOSCore]
ProductId=your-product-id
SandboxId=your-sandbox-id
DeploymentId=your-deployment-id
ClientId=your-client-id
ClientSecret=your-client-secret

; Optional settings (defaults shown)
bAutoInitialize=true
bTickEOS=true
bEnableOverlay=true
bEnableSocialOverlay=true

Tip: If you already use [OnlineSubsystemEOS] or [/Script/OnlineSubsystemEOS.EOSSettings], the plugin will read credentials from those sections as a fallback. You do not need to duplicate your credentials.

Step 4 — (Optional) OnlineSubsystemEOS Co-existence

If your project already has OnlineSubsystemEOS enabled and set as the default platform service, the plugin will automatically detect and borrow its EOS platform handle.

[OnlineSubsystem]
DefaultPlatformService=EOS

In this case:

• No second EOS handle is created — the plugin reuses the existing one safely.
• No ticker is started — the OSS already ticks EOS.
• You do not need the [EOSCore] section (though it is harmless to have it).

Step 5 — Configure a Stat in the Dev Portal

EOS Leaderboards are powered by Stats. To create one:

1. Go to Dev Portal → [Your Sandbox] → Stats
2. Click Create Stat and fill in:
   • Stat Name — the exact string you will pass to EOS Ingest Stat (e.g. score)
   • Aggregation Method — how EOS combines multiple ingests:

Step 6 — Configure a Leaderboard in the Dev Portal

1. Go to Dev Portal → [Your Sandbox] → Leaderboards
2. Click Create Leaderboard and fill in:
   • Leaderboard ID — the exact string you will pass to EOS Query Leaderboard (e.g. leaderboard_score)
   • Stat — select the stat you created above
   • Sort Order — Descending (highest score first) or Ascending
   • Start / End Date — optional time window (leave blank for a permanent leaderboard)

Step 7 — Verify Setup

In your game's BeginPlay (or GameInstance Init), call InitializeEOS and check the return value:

Event BeginPlay
  └─► InitializeEOS ──► (returns true) ──► Continue to Auth Login
                     └─► (returns false) ──► Log error / show error screen

If InitializeEOS returns false, check:

• Your credentials in DefaultEngine.ini are correct (no trailing spaces)
• The EOSCore section name is exactly [EOSCore]
• Your Sandbox and Deployment IDs match your Dev Portal environment

Subsystem Persistence

UEOSCoreLeaderboardSubsystem lives as long as the GameInstance. It persists across level changes automatically — you do not need to re-initialize EOS on each level load.

Log Category

All plugin logs use the LogEOSCore category. To see verbose logs, add to DefaultEngine.ini:

[Core.Log]
LogEOSCore=Verbose

Next Step

Once InitializeEOS returns true, follow the Example Project guide for the complete login → query → ingest flow.