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README.md

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 license: cc-by-nc-sa-4.0
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+# AlpaSim E2E Challenge 2026 — NuPlan / MTGS Track Data
+
+This dataset contains the official evaluation assets for the **NuPlan / MTGS Track** of the [AlpaSim E2E Closed-Loop Challenge 2026](https://huggingface.co/spaces/nvidia/AlpasimE2EClosedLoopChallenge2026).
+
+These resources are managed exclusively by the **trusted evaluator**. Contestants do **not** need to package or depend on them in their submitted driver images.
+
+---
+
+## Dataset Structure
+
+```
+MTGS_asset/
+└── navtest/
+    ├── assets/
+    │   ├── part001.tar.gz
+    │   ├── ...
+    │   └── part015.tar.gz   # MTGS neural rendering assets (~456 GB total)
+    └── configs.tar.gz       # navtest scene configurations
+
+trajdata_cache/
+└── nuplan_test.tar.gz       # trajdata cache for nuPlan test scenes
+```
+
+### `MTGS_asset/navtest/`
+
+Neural rendering assets used by the [MTGS](https://github.com/OpenDriveLab/MTGS) renderer during closed-loop evaluation. The evaluator mounts these assets into the simulator stack; contestant containers do not have direct access to them.
+
+### `trajdata_cache/nuplan_test.tar.gz`
+
+Pre-built [trajdata](https://github.com/NVlabs/trajdata) cache for the nuPlan test split. The evaluator uses this cache to initialize and drive nuPlan scenes during evaluation rollouts.
+
+---
+
+## How Evaluation Works
+
+1. The evaluator starts the full AlpaSim simulator stack (physics, traffic, MTGS renderer) using the assets in this dataset.
+2. The contestant's driver container receives rendered camera images and scene state over gRPC and must respond with control commands within **0.1 s** per `Drive` call.
+3. Results are aggregated and posted to the leaderboard.
+
+The official evaluation preset is `+e2e_challenge=ec2` (`topology=8gpu_36rollouts`): 12 contestant replicas across GPUs 4–7, each handling 3 concurrent rollouts.
+
+---
+
+## Contestant Submission Requirements
+
+- Implement `egodriver.EgodriverService` (see `src/grpc/alpasim_grpc/v0/egodriver.proto`).
+- Image size ≤ **40 GiB**; do not bundle nuPlan data, trajdata caches, navtest configs, or MTGS assets.
+- Outbound network access is blocked during evaluation; the root filesystem is read-only.
+- Writable scratch space: `/tmp` (2 GiB), `/run` (64 MiB).
+
+For full instructions see the [AlpaSim E2E Challenge README](https://huggingface.co/spaces/nvidia/AlpasimE2EClosedLoopChallenge2026).
+
+---
+
+## License
+
+This dataset is released under [CC BY-NC-SA 4.0](https://creativecommons.org/licenses/by-nc-sa/4.0/).