AlpaSim. E2E Closed Loop Challenge
2026 · NVIDIA AV Research · KE:SAI · HKU

AlpaSim E2E Closed Loop Challenge

A closed-loop benchmark for evaluating autonomous driving policies.

01 Overview

Welcome to the AlpaSim End to End Closed Loop Challenge. This competition invites teams to build autonomous driving policies and compare them head-to-head in realistic closed-loop simulation, where each policy's decisions shape the future scene it must handle.

Autonomous driving research has made major progress, but it remains hard to compare policies across labs and companies in a realistic, reproducible way. Open-loop evaluation is useful, but it misses the compounding effects that make driving hard: a small planning error can change future observations, interactions, and risk.

AlpaSim provides a shared simulator, public development data, starter tools, baseline policies, and a common containerized submission interface. Organizer-managed evaluation workers run submissions on private held-out scenarios and publish leaderboard results with both a policy capability score and a safety metric.

Across both tracks, the goal is not just to crown a winner. We want to learn which policy families are robust under distribution shift, where they fail, and how the community can make AV evaluation more trustworthy.

02 Announcements & Upcoming Changes

Registration closes October 18, 2026

New team registration closes on October 18, 2026. The submission deadline remains October 31, 2026.

Final-run selection and configuration

At least the top three teams in each track will be selected for final runs. Organizers may include additional teams depending on how close the leaderboard scores are.

The Harmonizer diffusion model will be disabled for initial runs. It will be enabled for PAI final runs and remain disabled for nuPlan final runs.

Each selected contestant will receive one additional evaluation run in PAI and two additional evaluation runs in nuPlan to reduce potential variance in the final results.

03 Competition Status & Known Issues

This is the current competition deployment on the e2e_challenge branch.

Known issues

Public nuPlan navtest MAP route foldbacks: In 10 of 1,485 public scenarios, near-stationary position noise can make MAP route generation select the wrong lane and fail its foldback check before the driver runs. This does not affect the private competition set. For local evaluation, use the recorded ego pose yaw for MAP lane matching instead of heading inferred from consecutive positions, or exclude the affected scenarios from local comparisons. The fix is planned for public main; e2e_challenge will remain unchanged during the competition.

Let us know on the AlpaSim GitHub issues page if you find anything.

Initial re-opening commit

cd713e0d0563352ce45b99d0a53a7173d581bde2

This was the initial re-opening deployment on the e2e_challenge branch. Its configuration included the settings below.

Official submission limit: three per team per UTC calendar month

Teams may make three official submissions per UTC calendar month, shared across PAI and nuPlan. The allowance resets at 00:00 UTC on the first day of each month; unused submissions do not carry forward. Accepted submissions count even if evaluation fails. Use the CLI limits command to check your team's remaining allowance.

Each warmup track has a separate allowance of three submissions per team in a rolling 30-day window. Warmup submissions do not consume the official allowance.

Longer PAI evaluation turnaround

PAI evaluations use the final, larger evaluation suite and may take nearly an order of magnitude longer to complete.

Tunable controller parameters

Teams can now provide values for tunable controller parameters at submission time.

Terms and Conditions Added

Per internal legal guidance, terms and conditions have been added for competitors. All registered teams may submit, but some teams may be ineligible for prizes. After registering and before submitting, please read and accept the terms through the challenge command-line tool.

Full camera coverage

PAI rollouts now include rear-facing cameras, giving drivers image coverage around the full ego vehicle rather than only its forward and side views.

Ego footprint in the driver API

The rollout specification now includes the ego vehicle bounding box and its pose relative to the ego rig, so drivers can account for the vehicle footprint used by evaluation.

Local leaderboard construction

New local evaluation utilities include a curated PAI validation split and reference runs, so teams can construct a local ranking and better understand the evaluation criteria. The local score scale is illustrative and is not directly comparable to the official leaderboard.

Local nuPlan closed-loop evaluation

Teams can now run the full public navtest suite locally for the nuPlan track. It is a public development suite, not the private official competition suite, and no nuPlan reference bundle is included yet.

Known issues

nuPlan off-road scoring: Off-road calculations were not enabled for nuPlan evaluations. In addition, issue #180 identifies a problem with the off-road algorithm. Additional testing preceded the code update and redeployment. Organizers will rerun only the evaluation stage for existing nuPlan submissions.

This previous version is retained for reference. It was also on the e2e_challenge branch.

Ground-truth violations in some scenes

Some soft-open scenes could produce violations even when following the ground-truth path. This was fixed in the initial re-opening commit, cd713e0d0563352ce45b99d0a53a7173d581bde2.

04 Registration

Registration is limited to teams affiliated with academic or industry organizations. To protect limited evaluation capacity and ensure fair participation, the team captain's verified Hugging Face primary email must be an organization address.

Registrations are reviewed to prevent duplicate or non-genuine accounts from circumventing team-level participation limits. Independent groups from the same organization are welcome: identify your lab, department, or group and briefly describe the project in the registration form.

Full challenge rules and submission limits are in the Contestant Guide.

05 Rules & Fair Play

The challenge is designed to compare independently developed policies under a shared, organizer-managed evaluation protocol. These rules protect that comparison and the limited evaluation capacity available to all teams.

Team participation

Each participant may belong to only one registered team. Submission limits apply at the team level across its authorized submitters; teams and participants must not coordinate submissions or share accounts to bypass those limits. Multiple independent teams from the same organization are welcome.

Permitted resources

Award-eligible nuPlan submissions may use only publicly available datasets, annotations, and model weights. PAI-AV submissions may use private resources when the team has the right to use them and provides a high-level disclosure of their use.

Evaluation integrity

Submissions must not use hidden scenario information, private route identifiers, or any information unavailable to the policy during evaluation. Attempts to exploit the leaderboard, simulator, or platform; attack the service; or otherwise undermine fair evaluation may result in disqualification.

Reproducibility and review

Submitted policies must follow the published container contract and evaluation constraints. Organizers may request code, logs, or method details for award candidates, disputed results, or suspected rule violations, and may invalidate non-reproducible submissions.

Technical reports and awards

Award eligibility requires a final valid submission and a concise technical report for the relevant track. Reports are limited to four pages, excluding references and optional appendices, and should use the AlpaSim technical report template, which uses an attributed adaptation of the NeurIPS 2026 layout. Innovation prizes will be determined through organizer review of these reports and may overlap with leaderboard placement awards.

Use the AlpaSim GitHub issues for questions, reproducible bugs, and rule clarifications. Material clarifications will be reflected here.

06 Challenge Tracks

The competition has two complementary tracks, covering both large-scale geographically diverse driving data and a lower-barrier entry point for teams working with established nuPlan-style workflows.

Track 1 - PAI-AV

Physical AI AV Track

The larger-scale setting for testing whether promising policies hold up as scenario diversity and long-tail coverage increase.

Competition scenes come from Denmark, France, Germany, Japan, South Korea, Spain, Sweden, the United Kingdom, and the United States.

Track 2 - nuPlan

nuPlan Track

A lower-barrier track for teams building on the widely used nuPlan ecosystem or NAVSIM-style development workflows.

The nuPlan track uses a private evaluation dataset.

07 Timeline

  1. 2026-06-15 Competition goes live Registration, public data, starter tools, and submission instructions open.
  2. 2026-09-09 Competition reopens Registration, submissions, and leaderboards are available again.
  3. 2026-09-15 Rules and submission format freeze Final rules, metric implementation, Docker base image, and public submission format freeze except for critical fixes.
  4. 2026-10-18 Registration cutoff New team registration closes.
  5. 2026-10-31 Public leaderboard closes Teams select one final valid container per track. Technical reports are due.
  6. 2026-11-15 (target) Target date for final results and winner announcements Final results and award decisions are targeted for release to participants on this date, subject to available compute and evaluation load.
  7. During NeurIPS 2026 Challenge results shared Winners and selected participants present results; organizers share final analysis and lessons learned.

08 Prizes

Each track will award two NVIDIA DGX Spark prizes: one for first place and one for an innovative solution.

The winners will receive a DGX Spark with an approximate retail value of USD $4,700. The prize must be accepted as awarded and is non-transferable, non-exchangeable, and has no cash value. NVIDIA is not responsible for any costs or taxes associated with prize acceptance. Teams marked (host) on the leaderboard are excluded from prizes.

DGX

PAI-AV Track

Two NVIDIA DGX Spark prizes awarded.

DGX

nuPlan Track

Two NVIDIA DGX Spark prizes awarded.

09 Documentation Links

10 Organizers

This competition is hosted by NVIDIA's Autonomous Vehicle Research Group, KE:SAI, and HKU.

11 Leaderboard