diff --git a/_docs/03_implementation/jetson_harness_setup.md b/_docs/03_implementation/jetson_harness_setup.md
new file mode 100644
index 0000000..50e19e6
--- /dev/null
+++ b/_docs/03_implementation/jetson_harness_setup.md
@@ -0,0 +1,175 @@
+# Jetson e2e Harness — Operator Setup
+
+AZ-615 / AZ-602 cycle-2. Documents the one-time operator-side setup
+that makes `scripts/run-tests-jetson.sh` work against a Jetson Orin Nano
+reachable from the developer Mac over SSH.
+
+## Why a separate Jetson harness exists
+
+The Colima/Tier-1 smoke harness (`docker-compose.test.yml` +
+`tests/e2e/Dockerfile`) verifies wiring, env config, fixture loading,
+auto-sync, and JSONL schema — everything UP TO the GPU boundary. But
+all three C7 inference strategies
+(`pytorch_fp16_runtime.py`, `tensorrt_runtime.py`,
+`onnx_trt_ep_runtime.py`) are CUDA-only by design (`model.half().cuda()`
+on `pytorch_fp16_runtime.py:189`, no CPU fallback). The full Reality
+Gate — including C3 matcher + C7 inference — therefore needs a
+CUDA-capable host.
+
+The Jetson harness runs the same test tree (`tests/e2e/`) on the Jetson
+with `GPS_DENIED_TIER=2`, which turns OFF the auto-skip for
+`@pytest.mark.tier2` tests (see `tests/conftest.py:31-44`).
+
+## Hardware contract
+
+Operator-confirmed environment (2026-05-17):
+
+* Jetson Orin Nano dev kit
+* JetPack 6.2.2+b24
+* L4T R36.5.0 (Jan 2026)
+* nvidia-container-toolkit 1.16.2
+* ≥ 30 GB free on `/var/lib/docker` (l4t-pytorch base image ~7 GB +
+  build cache + fixture volumes)
+* Swap enabled (Orin Nano has 8 GB RAM; PyTorch + TensorRT loads spike)
+
+## One-time setup
+
+### 1. SSH key + alias (on the Mac)
+
+```bash
+# Generate a dedicated keypair (separate from your daily-dev key)
+ssh-keygen -t ed25519 -a 100 -f ~/.ssh/id_ed25519_jetson_e2e \
+    -C "jetson-e2e $(date +%Y-%m-%d)"
+
+# Push the public half to the Jetson (asks for the Jetson password once)
+ssh-copy-id -i ~/.ssh/id_ed25519_jetson_e2e.pub <jetson-user>@<jetson-ip>
+
+# Verify the Jetson's host key (run this ON the Jetson, via HDMI/serial,
+# not over the LAN you're about to trust):
+#   ssh-keygen -lf /etc/ssh/ssh_host_ed25519_key.pub
+# Then compare against what the Mac sees on first connect. Accept only
+# if they match.
+
+# Wire up ~/.ssh/config (gitignored, never committed)
+cat >> ~/.ssh/config <<'EOF'
+Host jetson-e2e
+    HostName <jetson-ip>
+    User <jetson-user>
+    IdentityFile ~/.ssh/id_ed25519_jetson_e2e
+    IdentitiesOnly yes
+    AddKeysToAgent yes
+    UseKeychain yes
+    StrictHostKeyChecking yes
+    ServerAliveInterval 30
+    ServerAliveCountMax 4
+EOF
+
+# Cache the passphrase into macOS Keychain (one-time)
+ssh-add --apple-use-keychain ~/.ssh/id_ed25519_jetson_e2e
+```
+
+### 2. Restrict the key's scope on the Jetson (recommended)
+
+Edit `~/.ssh/authorized_keys` on the Jetson and prefix the line that the
+`ssh-copy-id` step appended:
+
+```
+from="<mac-lan-ip>",no-port-forwarding,no-X11-forwarding,no-agent-forwarding ssh-ed25519 AAAA…  jetson-e2e
+```
+
+Optionally lock to "only run the e2e driver" by adding
+`command="docker compose -f /home/jetson/gps-denied-onboard/docker-compose.test.jetson.yml up --abort-on-container-exit"` —
+the key can't get a general shell, only invoke that one command.
+
+### 3. Harden sshd (optional, recommended for an exposed test rig)
+
+On the Jetson, create `/etc/ssh/sshd_config.d/10-e2e.conf`:
+
+```
+PasswordAuthentication no
+PermitRootLogin no
+PubkeyAuthentication yes
+```
+
+Then `sudo systemctl reload ssh`.
+
+### 4. Verify the Jetson Docker + GPU pipeline
+
+```bash
+ssh jetson-e2e 'docker run --rm --runtime=nvidia --gpus all \
+    nvcr.io/nvidia/l4t-base:r36.4.0 nvidia-smi'
+```
+
+Expected output: a `nvidia-smi`-style table listing the Orin GPU. If
+this fails with "runtime not found" or "no GPU devices", install
+`nvidia-container-toolkit` and `sudo systemctl restart docker`.
+
+### 5. Confirm disk + swap
+
+```bash
+ssh jetson-e2e 'df -h /var/lib/docker && swapon --show && free -h'
+```
+
+Need ≥ 30 GB free on `/var/lib/docker`. Swap should be at least 4 GB
+(JetPack default is 4 GB zram).
+
+## Running the harness
+
+From the developer Mac, repo root:
+
+```bash
+bash scripts/run-tests-jetson.sh
+```
+
+What happens:
+
+1. `rsync` source → `jetson-e2e:~/gps-denied-onboard/` (excludes `.git`,
+   `__pycache__`, build artefacts; LFS pointers transfer as text).
+2. `ssh jetson-e2e docker compose -f docker-compose.test.jetson.yml build e2e-runner`
+3. `ssh jetson-e2e docker compose ... up --abort-on-container-exit --exit-code-from e2e-runner`
+4. stdout / stderr stream to the Mac terminal; exit code propagates.
+
+Override the alias or remote dir if your setup differs:
+
+```bash
+JETSON_SSH_ALIAS=other-host JETSON_REMOTE_DIR=~/somewhere/else \
+    bash scripts/run-tests-jetson.sh
+```
+
+## Smoke vs. Reality Gate split — at a glance
+
+| Test category | Marker | Colima (Tier-1) | Jetson (Tier-2) |
+|---------------|--------|-----------------|-----------------|
+| AC-4a AST scan | (none) | runs | runs |
+| AC-4b byte-equality | (none) | runs | runs |
+| AC-7 skip-gate self-check | (none) | runs | runs |
+| AC-9 helper unit tests | (none) | runs | runs |
+| AC-1 / AC-2 / AC-3 / AC-5 / AC-6 (heavy) | `tier2` | **SKIPPED** | runs |
+| AC-8 operator workflow | `skip` (AZ-616 blocks) | skipped | skipped |
+
+`GPS_DENIED_TIER` env var controls the auto-skip:
+
+* `GPS_DENIED_TIER=1` (Colima default) → `tier2` / `gpu` / `docker`
+  marked tests auto-skipped via `tests/conftest.py:31-44`.
+* `GPS_DENIED_TIER=2` (Jetson default) → all markers active; everything
+  runs (subject to other skip gates like `RUN_REPLAY_E2E`).
+
+## Troubleshooting
+
+| Symptom | Likely cause | Fix |
+|---------|--------------|-----|
+| `cannot reach 'ssh jetson-e2e' non-interactively` | Agent isn't unlocked or key not in `authorized_keys` | `ssh-add -l` on Mac; check `~/.ssh/authorized_keys` on Jetson |
+| `docker: Error response from daemon: could not select device driver "nvidia"` | nvidia-container-toolkit missing or daemon not restarted after install | `sudo apt install nvidia-container-toolkit && sudo systemctl restart docker` |
+| `torch.cuda.is_available() == False` inside the container | `runtime: nvidia` block missing, or building on x86 host | Verify `docker-compose.test.jetson.yml` has `runtime: nvidia`; rebuild on the Jetson |
+| `replay.auto_sync.ac8_validation_failed` | AZ-614 (tlog time-base mismatch) — not a harness bug | Fix AZ-614 in `tests/e2e/replay/_tlog_synth.py` |
+| `pull access denied for nvcr.io/nvidia/l4t-pytorch` | NGC requires login for some tags | `docker login nvcr.io` (use NGC API key from developer.nvidia.com) |
+
+## Related Jira
+
+* AZ-615 — this harness (Jetson runner story)
+* AZ-616 — replace `mock-sat` with real `../satellite-provider` service
+* AZ-617 — mark heavy ACs with `tier2` (already applied; this story
+  documents and verifies the auto-skip)
+* AZ-614 — tlog time-base mismatch (currently blocks the heavy ACs
+  from reaching the GPU stage)
+* AZ-602 — parent Epic: E2E Tier-1 harness rehabilitation
diff --git a/docker-compose.test.jetson.yml b/docker-compose.test.jetson.yml
new file mode 100644
index 0000000..680ac0c
--- /dev/null
+++ b/docker-compose.test.jetson.yml
@@ -0,0 +1,98 @@
+# Tier-2 e2e harness — Jetson Orin Nano (JetPack 6.x, L4T R36.x).
+#
+# AZ-615: companion compose file to `docker-compose.test.yml` that runs
+# the full Reality Gate on a CUDA-capable host. Used via `ssh jetson-e2e
+# "docker compose -f docker-compose.test.jetson.yml up ..."` driven by
+# `scripts/run-tests-jetson.sh`.
+#
+# Difference vs. docker-compose.test.yml:
+#   * `runtime: nvidia` + `gpus: all` on `e2e-runner` so the SUT can
+#     resolve `model.half().cuda()` against the Orin GPU.
+#   * `GPS_DENIED_TIER=2` — turns OFF the auto-skip for `@pytest.mark.tier2`
+#     ACs (see tests/conftest.py:31-44). The heavy ACs (AC-1, AC-2, AC-3,
+#     AC-5, AC-6) actually run.
+#   * Builds from `tests/e2e/Dockerfile.jetson` (l4t-pytorch base).
+#   * Companion / db / mock-sat continue to come from the root
+#     `docker-compose.yml` via `extends:` (same as Colima) — they have ARM64
+#     tags via the existing build pipeline.
+#
+# Satellite-provider integration (real .NET service at ../satellite-provider/)
+# is tracked separately under AZ-616 and lands as a follow-up patch to this
+# file once the auth + tile-source strategy is decided.
+
+services:
+  companion:
+    extends:
+      file: docker-compose.yml
+      service: companion
+    environment:
+      LOG_LEVEL: INFO
+
+  operator-orchestrator:
+    extends:
+      file: docker-compose.yml
+      service: operator-orchestrator
+
+  mock-sat:
+    extends:
+      file: docker-compose.yml
+      service: mock-sat
+
+  db:
+    extends:
+      file: docker-compose.yml
+      service: db
+
+  e2e-runner:
+    build:
+      context: .
+      dockerfile: tests/e2e/Dockerfile.jetson
+    image: gps-denied-onboard/e2e-runner:jetson
+    # nvidia-container-runtime exposes the Tegra GPU + libcuda mounts.
+    # Without this block the container starts but `torch.cuda.is_available()`
+    # returns False and every tier2 AC errors at `.cuda()`.
+    runtime: nvidia
+    deploy:
+      resources:
+        reservations:
+          devices:
+            - driver: nvidia
+              count: all
+              capabilities: [gpu]
+    depends_on:
+      companion:
+        condition: service_healthy
+      mock-sat:
+        condition: service_healthy
+      db:
+        condition: service_healthy
+    environment:
+      # Same FullSystemConfig env block as Colima — see comments in
+      # docker-compose.test.yml for the per-var rationale.
+      GPS_DENIED_FC_PROFILE: ardupilot_plane
+      # Tier-2 turns OFF the `tier2` / `gpu` auto-skip in tests/conftest.py
+      # so the heavy ACs in tests/e2e/replay/test_derkachi_1min.py actually
+      # execute. This is the WHOLE POINT of the Jetson harness.
+      GPS_DENIED_TIER: "2"
+      DB_URL: postgresql://gps_denied:dev@db:5432/gps_denied
+      SATELLITE_PROVIDER_URL: http://mock-sat:5100
+      COMPANION_URL: http://companion:8080
+      CAMERA_CALIBRATION_PATH: /opt/tests/fixtures/calibration/adti26.json
+      LOG_LEVEL: INFO
+      LOG_SINK: console
+      INFERENCE_BACKEND: pytorch_fp16
+      FDR_PATH: /var/lib/gps-denied/fdr
+      TILE_CACHE_PATH: /var/lib/gps-denied/tiles
+      MAVLINK_SIGNING_KEY: /opt/tests/fixtures/mavlink_signing/dev_key
+      RUN_REPLAY_E2E: "1"
+      BUILD_REPLAY_SINK_JSONL: "ON"
+    volumes:
+      - ./tests:/opt/tests:ro
+      - ./_docs/00_problem/input_data:/opt/_docs/00_problem/input_data:ro
+      - fdr-data:/var/lib/gps-denied/fdr
+      - tile-data:/var/lib/gps-denied/tiles
+
+volumes:
+  db-data: {}
+  fdr-data: {}
+  tile-data: {}
diff --git a/scripts/run-tests-jetson.sh b/scripts/run-tests-jetson.sh
new file mode 100755
index 0000000..5f75b89
--- /dev/null
+++ b/scripts/run-tests-jetson.sh
@@ -0,0 +1,115 @@
+#!/usr/bin/env bash
+# AZ-615: drive the Tier-2 Reality Gate e2e harness on a remote Jetson.
+#
+# Runs from the developer Mac. Assumes:
+#   * `ssh jetson-e2e` works via key auth + ~/.ssh/config (see
+#     _docs/03_implementation/jetson_harness_setup.md for one-time setup).
+#   * The Jetson has docker + nvidia-container-toolkit + ≥ 30 GB free on
+#     /var/lib/docker.
+#
+# Flow:
+#   1. rsync the working tree to the Jetson under ~/gps-denied-onboard/
+#      (excluding .git, LFS pointers, build artefacts).
+#   2. ssh into the Jetson and `docker compose build` the e2e-runner image
+#      against tests/e2e/Dockerfile.jetson.
+#   3. ssh again and `docker compose up --abort-on-container-exit
+#      --exit-code-from e2e-runner` so the local exit code reflects the
+#      remote test verdict.
+#   4. stdout / stderr stream back to the Mac terminal.
+#
+# Exit code propagates the docker-compose exit code (which == the
+# e2e-runner container's exit code, which == pytest's verdict).
+
+set -euo pipefail
+
+# ----------------------------------------------------------------------
+# Configuration
+
+SSH_ALIAS="${JETSON_SSH_ALIAS:-jetson-e2e}"
+REMOTE_DIR="${JETSON_REMOTE_DIR:-~/gps-denied-onboard}"
+COMPOSE_FILE="docker-compose.test.jetson.yml"
+
+# Repo root regardless of where the script is invoked from.
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+REPO_ROOT="$(cd "${SCRIPT_DIR}/.." && pwd)"
+
+# ----------------------------------------------------------------------
+# Pre-flight
+
+if ! command -v rsync >/dev/null 2>&1; then
+    echo "ERROR: rsync not on PATH — install with 'brew install rsync' or apt" >&2
+    exit 64
+fi
+
+if ! ssh -o BatchMode=yes -o ConnectTimeout=5 "${SSH_ALIAS}" true 2>/dev/null; then
+    cat >&2 <<EOF
+ERROR: cannot reach 'ssh ${SSH_ALIAS}' non-interactively. Configure
+       ~/.ssh/config + agent-based key auth per
+       _docs/03_implementation/jetson_harness_setup.md.
+EOF
+    exit 65
+fi
+
+echo "[run-tests-jetson] using ssh alias: ${SSH_ALIAS}"
+echo "[run-tests-jetson] remote dir:      ${REMOTE_DIR}"
+echo "[run-tests-jetson] compose file:    ${COMPOSE_FILE}"
+
+# ----------------------------------------------------------------------
+# Step 1: sync source
+
+# Exclusions kept deliberately narrow — we want the full src/, tests/,
+# _docs/, docker-compose*.yml, scripts/, pyproject.toml. We exclude:
+#   * .git — huge, no value on the Jetson
+#   * __pycache__ / *.pyc — host-arch bytecode, regenerated on Jetson
+#   * _build / build / dist — local CMake / setuptools output trees
+#   * node_modules — frontend artefacts, not needed by the harness
+#   * .venv / venv — host venv, would clobber the Jetson's Python env
+#   * .DS_Store — macOS metadata
+#   * *.tlog / *.bin / *.engine — large fixtures that exist on Jetson
+#     either via a separate fixture-sync step or are produced by the SUT
+# Git LFS pointers (134 B files) DO transfer — they're text. The
+# Jetson runs `git lfs pull` lazily for any LFS-tracked fixture it
+# actually needs.
+echo "[run-tests-jetson] rsync → ${SSH_ALIAS}:${REMOTE_DIR}/"
+rsync -avz --delete \
+    --exclude=.git/ \
+    --exclude='__pycache__/' \
+    --exclude='*.pyc' \
+    --exclude=_build/ \
+    --exclude=build/ \
+    --exclude=dist/ \
+    --exclude=node_modules/ \
+    --exclude=.venv/ \
+    --exclude=venv/ \
+    --exclude=.DS_Store \
+    --exclude='*.engine' \
+    "${REPO_ROOT}/" "${SSH_ALIAS}:${REMOTE_DIR}/"
+
+# ----------------------------------------------------------------------
+# Step 2: build the e2e-runner image on the Jetson
+
+# The image MUST be built on the Jetson — see Dockerfile.jetson comment
+# about Tegra-specific libs.
+echo "[run-tests-jetson] docker compose build e2e-runner (on Jetson)"
+# shellcheck disable=SC2087  # we want the heredoc to expand on the local side
+ssh "${SSH_ALIAS}" bash -s <<EOF
+set -euo pipefail
+cd "${REMOTE_DIR}"
+docker compose -f "${COMPOSE_FILE}" build e2e-runner
+EOF
+
+# ----------------------------------------------------------------------
+# Step 3: run
+
+# `--abort-on-container-exit` plus `--exit-code-from e2e-runner` makes
+# docker-compose propagate the runner's exit code, which we propagate
+# back to the local terminal via `ssh` returning that code. So `bash
+# scripts/run-tests-jetson.sh && echo OK` does the right thing locally.
+echo "[run-tests-jetson] docker compose up e2e-runner (on Jetson)"
+ssh "${SSH_ALIAS}" bash -s <<EOF
+set -euo pipefail
+cd "${REMOTE_DIR}"
+exec docker compose -f "${COMPOSE_FILE}" up \
+    --abort-on-container-exit \
+    --exit-code-from e2e-runner
+EOF
diff --git a/tests/e2e/Dockerfile.jetson b/tests/e2e/Dockerfile.jetson
new file mode 100644
index 0000000..74d4963
--- /dev/null
+++ b/tests/e2e/Dockerfile.jetson
@@ -0,0 +1,83 @@
+# Tier-2 e2e-runner image — Jetson Orin Nano (JetPack 6.x, L4T R36.x).
+#
+# AZ-615: companion image to `tests/e2e/Dockerfile` (Colima/Tier-1 smoke
+# harness) that runs the full Reality Gate — including C3 matcher + C7
+# inference — against a CUDA-capable GPU.
+#
+# Hardware contract (operator-confirmed, 2026-05-17):
+#   * Jetson Orin Nano, JetPack 6.2.2+b24, L4T R36.5.0
+#   * nvidia-container-toolkit ≥ 1.16
+#   * `docker run --runtime=nvidia ... nvidia-smi` returns the GPU
+#
+# Image layout mirrors the Colima Dockerfile (so AC-4 AST scan + bind
+# mounts work the same way):
+#   /opt/pyproject.toml
+#   /opt/src/gps_denied_onboard/...     (SUT package, editable install)
+#   /opt/tests/...                      (bind-mounted from host)
+#   /opt/_docs/00_problem/input_data/   (bind-mounted from host)
+#
+# Build context is the repo root (see `docker-compose.test.jetson.yml`
+# → `services.e2e-runner.build.context`).
+#
+# BUILD HOST: this image MUST be built ON the Jetson — cross-building
+# from x86 macOS produces images that miss Tegra-specific shared libs
+# the nvidia-container-runtime later mounts at run time.
+
+# ---------------------------------------------------------------------------
+# Base — l4t-pytorch ships JetPack runtime + PyTorch wheel ready for `.cuda()`
+#
+# Tag selection: NGC publishes l4t-pytorch on a slight lag from L4T BSP
+# releases. With BSP R36.5 on the device, the closest stable NGC tag at
+# author time is `r36.4.0-pth2.3-py3`. NVIDIA containers are
+# forward-compatible across one minor BSP (the container's userspace
+# can be slightly older than the host's L4T kernel). If a `r36.5.0-*`
+# tag is published, prefer it.
+#
+# Image lookup at run time: `docker manifest inspect nvcr.io/nvidia/l4t-pytorch:r36.4.0-pth2.3-py3`
+FROM nvcr.io/nvidia/l4t-pytorch:r36.4.0-pth2.3-py3 AS runtime
+
+ARG DEBIAN_FRONTEND=noninteractive
+# System deps mirror tests/e2e/Dockerfile + the Jetson runtime stack:
+#   * build-essential / libpq-dev / libspatialindex-dev — same as Colima
+#   * python3-pip / python3-venv — l4t-pytorch ships python but not always venv
+#   * libgl1 + libglib2.0-0 — OpenCV runtime libs (same reason as Colima)
+#   * libpq5 + libspatialindex-c6 — runtime side of psycopg + rtree
+# Note: CUDA / cuDNN / TensorRT come pre-baked in the base image — do NOT
+# attempt to apt-install them (would conflict with the Tegra-specific libs
+# the runtime mounts).
+RUN apt-get update && apt-get install -y --no-install-recommends \
+        ca-certificates \
+        build-essential \
+        libpq-dev \
+        libspatialindex-dev \
+        libpq5 \
+        libspatialindex-c6 \
+        libgl1 \
+        libglib2.0-0 \
+        python3-pip \
+        python3-venv \
+    && rm -rf /var/lib/apt/lists/*
+
+WORKDIR /opt
+
+# Editable SUT install. Skipping the `[inference]` extra because PyTorch +
+# torchvision are already provided by the l4t-pytorch base image with
+# Tegra-specific CUDA builds; reinstalling them from PyPI would clobber
+# the Tegra wheels with x86-compatible ones that lack the cuDNN / cuBLAS
+# linkage required by Orin.
+COPY pyproject.toml README.md ./
+COPY src ./src
+
+# `--break-system-packages` is needed because the l4t-pytorch base image
+# uses an externally-managed Python environment (PEP 668). The alternative
+# would be to layer a venv on top of the pre-installed torch, but that
+# would shadow the Tegra-tuned torch wheel and break `.cuda()`. The image
+# IS the environment; embracing system-pip is the path of least drift.
+RUN pip3 install --no-cache-dir --break-system-packages -e ".[dev]"
+
+# ENTRYPOINT mirrors the Colima Dockerfile — pytest discovers both
+# `tests/e2e/replay/` (heavy tier2 ACs run with GPS_DENIED_TIER=2) and
+# any future `tests/e2e/scenarios/` additions. Rootdir resolves to /opt
+# via the COPY'd pyproject.toml so `from tests.e2e.replay._helpers import ...`
+# works inside the test files.
+ENTRYPOINT ["pytest", "-q", "/opt/tests/e2e/"]
diff --git a/tests/e2e/replay/test_derkachi_1min.py b/tests/e2e/replay/test_derkachi_1min.py
index 8dc4017..409794c 100644
--- a/tests/e2e/replay/test_derkachi_1min.py
+++ b/tests/e2e/replay/test_derkachi_1min.py
@@ -56,6 +56,7 @@ _HEAVY_SKIP = pytest.mark.skipif(
 # AC-1: CLI exits 0; JSONL line count matches tlog GLOBAL_POSITION_INT count
 
 
+@pytest.mark.tier2
 @_HEAVY_SKIP
 def test_ac1_exits_0_jsonl_count_match(replay_runner, derkachi_replay_inputs) -> None:
     # Act
@@ -97,6 +98,7 @@ _ESTIMATOR_OUTPUT_KEYS = frozenset(
 )
 
 
+@pytest.mark.tier2
 @_HEAVY_SKIP
 def test_ac2_jsonl_schema_match(replay_runner) -> None:
     # Act
@@ -121,6 +123,7 @@ def test_ac2_jsonl_schema_match(replay_runner) -> None:
 # AC-3: ≥ 80 % of emissions within 100 m of ground truth
 
 
+@pytest.mark.tier2
 @_HEAVY_SKIP
 @pytest.mark.xfail(
     reason=(
@@ -350,6 +353,7 @@ def test_ac4_encoder_byte_equality_via_transport_seam() -> None:
 # AC-5: Determinism (two runs differ by ≤ 1e-6 in position fields)
 
 
+@pytest.mark.tier2
 @_HEAVY_SKIP
 def test_ac5_determinism_two_runs_diff(replay_runner) -> None:
     # Act
@@ -378,6 +382,7 @@ def test_ac5_determinism_two_runs_diff(replay_runner) -> None:
 # AC-6: Pace timing
 
 
+@pytest.mark.tier2
 @_HEAVY_SKIP
 def test_ac6_pace_realtime_60s_within_5pct(replay_runner) -> None:
     # Act
@@ -391,6 +396,7 @@ def test_ac6_pace_realtime_60s_within_5pct(replay_runner) -> None:
     )
 
 
+@pytest.mark.tier2
 @_HEAVY_SKIP
 def test_ac6_pace_asap_under_30s(replay_runner) -> None:
     # Act