How AEXLAB Improved Infrastructure Stability for VAIL VR with AccelByte QA's Services

Shipping frequent updates is essential for live-service games. But every release introduces risk across matchmaking, identity services, and server orchestration.

To keep VAIL VR stable while maintaining its rapid release cadence, AEXLAB worked with our professional services team to continuously find and fix backend integration issues before they impacted their players.

• Studio: AEXLAB
• Game: VAIL VR
• Genre: Competitive multiplayer VR tactical shooter
• What they needed: A way to continuously validate backend integrations without slowing their development cadence
• How our QA services helped: Backend integration testing across matchmaking flows, identity services, server orchestration, and API/SDK usage
• Key results:
  
  • 45 backend integration issues identified across services
  • 80% of detected issues were critical or high severity
  • Issue volume dropped month-over-month (19 → 16 → 10)
  • Improved multiplayer stability and faster issue resolution
  • Developers able to maintain rapid release pace without incidents

The Studio and the Game

AEXLAB is a VR-focused studio building competitive multiplayer experiences. Their flagship title, VAIL VR, is a tactical shooter built for VR emphasizing skill-based gunplay and immersive matches.

As the game has grown, AEXLAB has maintained a frequent update cadence, continuously shipping gameplay improvements and new features. That pace puts real pressure on backend infrastructure.

For a competitive multiplayer game, the backend isn’t secondary to the experience. It is the experience.

Matchmaking, dedicated servers, player identity, and session management have to work correctly on every build. When they don’t, players notice instantly.

The Engineering Challenge

Live-service multiplayer games face a category of problems that most QA workflows don’t catch: backend integration bugs. These aren't crashes or UI regressions. They're subtler. Things like:

• API endpoints being called with incorrect parameters

• SDK implementations that diverged from the latest spec causing game clients to submit match tickets with 0 latency, routing players into suboptimal regions

• Matchmaking backfill logic that slowly fills the dedicated server fleet with near-empty sessions, pushing server counts toward capacity limits

• Dedicated server heartbeat failures that cause live games to drop mid-session

• Deprecated API endpoints still in the game client that return 404s after the API is decommissioned

• Identity and authentication flows that break silently across builds

The tricky part is that these issues rarely appear in isolation. 

They show up when the full stack is running together. For example, when a player actually tries to find a match, join a server, or authenticate. By then, you're either in late-stage testing or already in production.

AEXLAB’s development team was shipping updates frequently. The question wasn’t whether to slow down. It was how to keep validating the backend without turning every release into a risk.

Why Traditional QA Often Misses These Issues

Standard QA is built around what a tester can see: gameplay behavior, UI states, content loading, crash reproduction. That coverage is important, but it doesn't reach deep into backend logic. Backend integration testing is a different discipline. It focuses on:

• Whether API calls are correctly formed and handled

• Whether matchmaking state machines behave as designed

• Whether identity and authentication flows are intact across builds

• Whether session management holds up under concurrent load

• Whether server orchestration responds correctly to player actions

These aren't issues that show up in a gameplay play through. A tester can complete a full match and never trigger a malformed API call or a misconfigured queue. 

The bug is there, it's just waiting for a specific condition.

That gap between surface-level testing and backend validation is where most live-service incidents originate. Issues slip through because the testing layer doesn't go deep enough, not because engineers aren't paying attention.

The Solution: Backend-Focused QA Testing

AccelByte’s QA team worked directly with AEXLAB to run backend integration testing across VAIL VR's live-service infrastructure.

The focus wasn't gameplay. It was the interface between the game client and backend services covering:

• API and SDK validation: Verifying that the game client was calling services correctly and handling responses as expected.

• Matchmaking flows: Testing queue behavior, session creation, and edge cases in player matching

• Identity and authentication: Validating login flows, token handling, and entitlement checks

• Server orchestration:  Confirming that dedicated server lifecycle events were handled properly

• Multiplayer session scenarios: Running end-to-end session flows to catch integration mismatches across services

We validated new builds as they came in, working alongside the AEXLAB development team rather than as a separate downstream step. Several things made this integration effective:

• Direct Sentry access gave QA engineers real-time visibility into server errors and crash reports, allowing root causes, particularly in dedicated server behavior, to be identified without waiting on log requests from the team.

• Version control visibility kept QA aligned with the latest change list updates, so test coverage always reflected what was actually in the build.

• Platform admin access on Steam and Meta Developer accounts let AccelByte QA manage and switch test builds independently, removing the back-and-forth that slows down testing cycles.

• Specialized tooling including AccelByte's Visual Debugger and Fiddler for HTTP traffic inspection made it possible to trace unexpected API call patterns directly from the game client.

Across the 45 issues identified, identity and access management (IAM) was the most concentrated area with 6 issues, followed by dedicated server (DS) behavior with 5. 

Matchmaking, session handling, cloud save, and action phase each surfaced more problems, reflecting how broadly backend issues can be distributed across a stack.

Because these were caught during the build cycle rather than after deployment, the AEXLAB team could diagnose and fix them before players noticed any interruptions.

Improvements to Multiplayer Infrastructure

Early backend testing surfaced issues that would otherwise have reached players. 

Two examples show the range:

• Backfill misconfiguration: Session max capacity was being overwritten from 16 to 26 players, causing backfill operations to fail and dedicated server counts to climb toward fleet limits.

• Outdated SDK: The game client was submitting matchmaking tickets with 0 latency, silently routing players into suboptimal regions.

Both were caught and fixed before reaching production. The server fleet also benefited directly with clean backfill and session lifecycle logic, which means slots aren't consumed by stuck or near-empty sessions.

Catching issues earlier in the build cycle means fewer incidents, less debugging under pressure, and more time spent on shipping. For a small studio with a frequent release cadence, that compounds quickly.

The Impact

The results from AEXLAB's engagement with AccelByte QA were concrete.
45 backend integration issues identified across identity services, matchmaking, dedicated servers, cloud save, and more. The monthly trend tells the clearest story:

Two things are happening in that data:

• Total issue volume is declining from 19 to 16 to 10 reflecting genuine stability improvement.

• At the same time, the proportion of critical and high severity findings is rising sharply.

That second trend is significant. It means QA efforts were increasingly targeted at the most impactful problems, and that medium and low severity issues had been largely addressed. By February, 80% of what QA was finding was either critical or high severity, the kind of bugs that become production incidents.

Development velocity held steady throughout. AEXLAB continued shipping updates without backend disruptions during the engagement.

That second trend is significant. It means QA efforts were increasingly targeted at the most impactful problems, and that medium and low severity issues had been largely addressed. By February, 80% of what QA was finding was either critical or high severity, the kind of bugs that become production incidents.

Key Benefits

• Catching high-severity backend bugs earlier through focused testing. QA efforts increasingly surfaced the most impactful issues before they could affect live environments.
• Fixing backend issues before they became production incidents. Problems were resolved during the build cycle rather than after deployment.
• Maintaining development velocity. Engineers were able to stay focused on building new features instead of reacting to backend incidents.
• Development velocity held steady throughout. AEXLAB continued shipping updates without backend disruptions during the engagement.

Why This Matters for Live-Service Games

Multiplayer backend systems don't fail loudly. They degrade.

• A misconfigured matchmaking rule creates longer queues.
• An outdated SDK call causes inconsistent behavior.
• A session lifecycle bug leaves lobbies stuck.

For live-service games in particular, backend stability isn't a one-time problem, it's a continuous operational requirement. Every update introduces risk. The only way to manage that risk at pace is to validate integrations continuously and catch problems before they reach production.

AccelByte QA can work directly with your team to validate how your game client integrates with backend services before those issues reach your players.

Get in touch with us to discuss what backend QA could look like for your game.