diff --git a/README.md b/README.md
index 11945e7..59c5bc5 100644
--- a/README.md
+++ b/README.md
@@ -6,6 +6,8 @@ A fleet of drones flies fully autonomously: no internet uplink, no external acce
This repository describes how to build, deliver, test, and operate that platform: the storage layout, the sync strategy, the network trust model, the CI/CD chain, and the simulation environment that makes it all testable without touching real hardware.
+**New here?** Start with the one-pager: [00 — Executive overview](docs/00-executive.md) (includes how **MinIO** fits). Then the [design journey](docs/12-design-journey.md) if you want the narrative.
+
## Design principles
1. **Every drone is autonomous.** No cluster orchestrator spans the swarm; intermittent mesh connectivity makes that an anti-pattern. Coordination happens through data exchange, not through a control plane.
@@ -30,7 +32,7 @@ Honest map so a reader knows what runs today versus what is design intent.
| Peer query | Read-only SQL **gate** over HTTP explorer (keyword allow-list) | Same gate idea via **SSH forced command** + OS/engine hardening |
| Bulk sync | Visualised opportunistic transfer volume | rsync/rclone over persistent SSH between peers |
| Mesh trust | Ansible templates for WireGuard + ed25519 forced commands | Provisioned per-device keys; nothing joins at runtime |
-| Ground segment | k3d/Terraform sim: lake, Grafana, offload CronJob, optional MinIO | k3s warehouse, GitOps overlays, post-flight mirror |
+| Ground segment | k3d/Terraform sim: lake, Grafana, offload CronJob, **MinIO as T3** | k3s warehouse with MinIO, GitOps overlays, post-flight mirror |
| CI / delivery | GitHub Actions: pytest, smoke flight, Trivy, semver release + fleet manifest artifact | Self-hosted GitLab + registry inside the air gap (same stages) |
| Docs | Problem, architecture, ADRs, design journey, open questions | Living ADRs owned by the team |
@@ -40,6 +42,7 @@ Start from the [design journey](docs/12-design-journey.md) for the story; use th
| Document | Contents |
| --- | --- |
+| [00 — Executive](docs/00-executive.md) | **Start here** — one-page goal, sync rule, MinIO stance |
| [00 — Glossary](docs/00-glossary.md) | Terms and abbreviations used throughout |
| [01 — Problem statement](docs/01-problem-statement.md) | Goal, constraints, knowns vs assumptions |
| [02 — Architecture](docs/02-architecture.md) | On-board layers, service composition, communication planes |
@@ -49,13 +52,13 @@ Start from the [design journey](docs/12-design-journey.md) for the story; use th
| [06 — Environments](docs/06-environments.md) | Drone / ground warehouse / dev-simulation infrastructures |
| [07 — Observability](docs/07-observability.md) | Logs, service metrics, hardware telemetry |
| [08 — Roadmap](docs/08-roadmap.md) | Dependency graph, simple to complex |
-| [09 — Open questions](docs/09-open-questions.md) | Known unknowns and proposed answers |
+| [09 — Open questions](docs/09-open-questions.md) | Known unknowns and proposed answers (incl. MinIO placement) |
| [10 — Domain context](docs/10-domain-context.md) | Swarm autonomy principles this design builds on |
| [11 — CI/CD & delivery](docs/11-cicd-delivery.md) | Pipelines, registry, dev containers, fleet releases |
-| [12 — Design journey](docs/12-design-journey.md) | **Start here** — a narrative walk-through of how the design came together, linking into the code |
+| [12 — Design journey](docs/12-design-journey.md) | Narrative walk-through linking into the code |
| [ADRs](docs/adr/) | Architecture Decision Records — the decisions behind the above, in the order they were made |
-New here? Read the [design journey](docs/12-design-journey.md) first: it tells the story chronologically and links straight into the code and decisions. The design principles below are the *what*; the [ADRs](docs/adr/) are the *why and when* — each principle traces to a dated, immutable decision record.
+New here? Read the [executive overview](docs/00-executive.md) first, then the [design journey](docs/12-design-journey.md) if you want the story. The design principles above are the *what*; the [ADRs](docs/adr/) are the *why and when*.
## Runnable parts
diff --git a/docs/00-executive.md b/docs/00-executive.md
new file mode 100644
index 0000000..98092cd
--- /dev/null
+++ b/docs/00-executive.md
@@ -0,0 +1,61 @@
+# 00 — Executive overview
+
+A one-page map of the proposal. Details and trade-offs live in the linked docs.
+Nothing here is a mandate: it is a from-scratch platform sketch the team can
+reshape once real constraints are on the table.
+
+## Goal
+
+Build an **on-prem, air-gapped data platform** for an autonomous drone swarm:
+accumulate sensor and detection data on each unit, share only what peers need in
+flight, and offload complete flights to a ground warehouse for replay and
+training.
+
+## Constraints (given)
+
+- No internet / no external access in flight; data stays inside the system.
+- Each drone is autonomous; mesh links are intermittent — **no swarm-wide orchestrator**.
+- On-board today: **Docker Compose**, **DuckDB**, YOLO-like video analytics; **Parquet** under evaluation.
+- **MinIO is already in the stack** — exact placement not fully known yet (see below).
+- Ground side can run lightweight Kubernetes; this proposal keeps k3s **on the ground only**.
+
+## Data contract (proposed)
+
+| What | Where | Crosses the air? |
+| --- | --- | --- |
+| Raw telemetry | Local NVMe (Parquet / Hive layout) | **No** — offloads after landing |
+| Pose / detections (derived) | Local store + peer pub/sub | **Yes** — small, budgeted |
+| Full flight archive | Ground warehouse (Parquet + object store) | After landing only |
+
+One layout on every floor so offload is a **mirror**, not a migration
+([03 — Data platform](03-data-platform.md)).
+
+## Sync rule
+
+1. **Fast path:** compact pose frames (~45 B @ 5 Hz) + event-shaped detections.
+2. **Bulk path (peers):** sealed derived partitions when the link allows
+ (rsync/SSH proposed; alternatives open).
+3. **Never** push raw high-rate telemetry peer-to-peer in flight.
+
+## MinIO (first-class, placement TBD)
+
+MinIO is treated as **already chosen infrastructure**, not something to rip out.
+
+| Role | Stance in this sketch |
+| --- | --- |
+| **Ground warehouse (T3)** | **Primary home** — S3 API under the Parquet lake / offload target |
+| **On-board (drone)** | **Default: no** — competes with flight-critical CPU/RAM; local Parquet + DuckDB is enough for the hot path |
+| **On-board exception** | Not excluded if a team already relies on an S3 API in Compose; then derived-only, never the 5 Hz pose path |
+| **5 Hz pose / collision state** | **Not MinIO** — pub/sub (UDP in the PoC; Zenoh proposed) |
+| **Inter-drone history catch-up** | Prefer pull of sealed partitions (SSH/rsync); MinIO replication only if ops already standardised on it |
+
+Open item for the team: document how MinIO is used today, then lock T2/T3 roles
+([09 — Open questions](09-open-questions.md)).
+
+## What to read next
+
+1. [12 — Design journey](12-design-journey.md) — narrative + deep links into code
+2. [Implemented vs proposed](../README.md#implemented-now-vs-proposed-next) — PoC vs production intent
+3. [09 — Open questions](09-open-questions.md) — including MinIO placement
+
+Live visual PoC: [swarm.produktor.io](https://swarm.produktor.io/) (same access as this repository).
diff --git a/docs/00-glossary.md b/docs/00-glossary.md
index e7fc14b..9a3248e 100644
--- a/docs/00-glossary.md
+++ b/docs/00-glossary.md
@@ -55,7 +55,7 @@ Terms and abbreviations used throughout this proposal.
| **Docker Compose** | Declarative multi-container runtime; the only orchestrator on board a drone |
| **k3s** | Lightweight Kubernetes distribution; used on the ground only |
| **Dev Container** | Reproducible containerized development environment definition |
-| **MinIO** | S3-compatible object store; runs on-board for derived data and on the ground as the warehouse backend |
+| **MinIO** | S3-compatible object store **already in the stack**; default home is the **ground warehouse (T3)**. On-board use is an exception, not the baseline |
| **Registry mirror** | Local copy of a container registry inside the air gap; drones pull images from it |
| **OTA** | Over-the-air update — delivered before a mission while docked, never mid-flight |
| **Fleet release manifest** | A versioned lockfile pinning every artifact (image digests, model weights, schemas, configs) that defines one fleet version |
diff --git a/docs/01-problem-statement.md b/docs/01-problem-statement.md
index 4f3e809..27c18a1 100644
--- a/docs/01-problem-statement.md
+++ b/docs/01-problem-statement.md
@@ -28,7 +28,7 @@ Plus everything a platform needs around that: reproducible builds and deployment
- The current on-board software is **Docker Compose** with two services: **sensor ingestion** and **video-stream object detection** (a YOLO-like model; weights and approaches vary).
- **DuckDB** is already in use for local data handling.
- **Parquet** adoption is at the evaluation stage — the storage layout in this proposal is the core of what is being asked.
-- **MinIO** is available and considered as the inter-drone sync mechanism.
+- **MinIO** is already in the stack. Exact placement (ground vs on-board vs sync path) was not fully specified in the brief; this proposal treats MinIO as **first-class ground-warehouse infrastructure** by default and keeps on-board MinIO as an open option — see [00 — Executive](00-executive.md) and [09 — Open questions](09-open-questions.md).
- A **lightweight Kubernetes** exists in the ecosystem; this proposal scopes it to ground infrastructure only (see [02 — Architecture](02-architecture.md)).
- After landing, each drone's data is **offloaded to an on-prem warehouse** for replay and iterative model training.
- Mission intent (declarative goals) reaches the swarm over a narrow **C2 channel**; there is no continuous ground link in flight.
@@ -43,6 +43,7 @@ Plus everything a platform needs around that: reproducible builds and deployment
| A4 | Missions are bounded (battery), so a "flight" is the natural unit of data lifecycle | Return-to-base on low energy implies discrete flight sessions |
| A5 | Mission logic consumes the data platform as a service and is out of scope here | Flight control, planning, and model training are separate concerns |
| A6 | A development-only telemetry channel exists on the bench and is absent from production builds | Standard practice; production radio profile carries C2 + swarm data plane only |
+| A7 | **MinIO's primary home is the ground warehouse (T3), not the drone** | On-board object store competes with flight-critical CPU/RAM; local Parquet + DuckDB already cover the hot path. On-board MinIO is not excluded if ops already depend on an S3 API in Compose |
## Out of scope
diff --git a/docs/02-architecture.md b/docs/02-architecture.md
index 29b5a2b..0d76538 100644
--- a/docs/02-architecture.md
+++ b/docs/02-architecture.md
@@ -21,11 +21,12 @@ graph TB
HOOK["event hook
fires on new derived data"]
PUB["state publisher
pub/sub broadcast"]
BULK["bulk sync
rsync over SSH"]
- MINIO["MinIO
optional derived bucket"]
QAPI["query API
SQL-over-SSH"]
end
end
+ MINIO[("MinIO — ground warehouse T3
already in the stack")]
+
SENSORS --> WRITER
VIDEO -->|detections| WRITER
WRITER --> NVME
@@ -33,15 +34,16 @@ graph TB
DUCK --> NVME
WRITER -->|derived rows| HOOK
HOOK --> PUB
- HOOK --> MINIO
HOOK --> BULK
QAPI --> DUCK
PUB -.->|mesh pose| PEERS["peer drones"]
BULK -.->|sealed partitions| PEERS
QAPI -.->|on demand| PEERS
+ NVME -->|post-flight offload| MINIO
```
-MinIO stays available where an S3 API helps (on-board derived datasets, ground warehouse). **In-flight peer bulk sync is SSH/rsync**, not object-store replication — see [04 — Swarm sync](04-swarm-sync.md).
+**MinIO** is already in the stack and is the **default ground warehouse (T3)** behind offload — keep it, do not rip it out. Default sketch: **not on the drone** (CPU/RAM budget); on-board MinIO remains an allowed exception if Compose already depends on an S3 API. **In-flight peer bulk sync is SSH/rsync** (or team-standard MinIO replication if that is already how ops works) — never the 5 Hz pose path. See [00 — Executive](00-executive.md) and [04 — Swarm sync](04-swarm-sync.md).
+
### Layer 1 — Ingestion
- `sensor-ingest` subscribes to sensor sources (ROS 2 topics where available, raw drivers otherwise) and normalizes them into typed streams: IMU, barometer, temperature, LiDAR, RSSI, power, and so on.
@@ -56,10 +58,11 @@ MinIO stays available where an S3 API helps (on-board derived datasets, ground w
### Layer 3 — Serving and sync
-- The **event hook** is the on-board "lambda": when the writer lands new *derived* rows (state, detections), it triggers registered actions — broadcast, optional MinIO put, bulk-sync hint, or a local mission-logic callback. Nothing polls.
+- The **event hook** is the on-board "lambda": when the writer lands new *derived* rows (state, detections), it triggers registered actions — broadcast, bulk-sync hint, or a local mission-logic callback. Nothing polls.
- The **state publisher** broadcasts compact position/attitude/detection payloads over the mesh pub/sub (UDP in the PoC; Zenoh proposed — [04](04-swarm-sync.md)).
-- **Bulk sync** pulls sealed derived partitions from peers over persistent SSH (rsync delta transfer). MinIO is optional where an S3 API is wanted; it is **not** the in-flight peer replication path.
+- **Bulk sync** pulls sealed derived partitions from peers over persistent SSH (rsync delta transfer). If the team already operates MinIO replication for that job, reuse it — do not invent a second path. Pose traffic never goes through MinIO.
- **Peer queries** are read-only DuckDB SQL — HTTP explorer gate in the PoC; **SSH forced commands** proposed for flight (SELECT-only gate, read-only OS user, columnar responses — [04](04-swarm-sync.md)).
+- **MinIO** sits on the **ground** as T3 by default ([00 — Executive](00-executive.md)); on-board MinIO is an explicit exception, not the baseline.
## Communication planes
diff --git a/docs/03-data-platform.md b/docs/03-data-platform.md
index 1002bab..b28714a 100644
--- a/docs/03-data-platform.md
+++ b/docs/03-data-platform.md
@@ -68,11 +68,13 @@ Same format on every floor; only volume, retention, and location change:
| Floor | Where | Contents | Retention |
| --- | --- | --- | --- |
| **T0 — hot** | RAM / DuckDB in-process | Sliding window of the last minutes; what mission logic queries in flight | Minutes |
-| **T1 — warm** | Drone NVMe | Full raw `telemetry` + `detections` + `state` of the current flight; never leaves the drone in flight | Current flight (+ quota-based headroom) |
-| **T2 — shared** | On-board MinIO bucket | Derived data only (`detections`, `state`), replicated opportunistically across the swarm | Current mission |
-| **T3 — warehouse** | Ground on-prem object store + Parquet lakehouse | Every flight of every drone, forever; replay, analytics, model training | Years |
+| **T1 — warm** | Drone NVMe (Parquet) | Full raw `telemetry` + `detections` + `state` of the current flight; never leaves the drone in flight | Current flight (+ quota-based headroom) |
+| **T2 — shared** | Peer-derived cache on NVMe (Parquet) | Derived data only (`detections`, `state`) pulled from peers when the link allows | Current mission |
+| **T3 — warehouse** | Ground **MinIO** (or equivalent) + Parquet lakehouse | Every flight of every drone; replay, analytics, model training — **primary MinIO home** | Years |
| **T4 — dev** | Engineer laptop / sim farm | Slices pulled from T3, or synthetic data from the simulator | Ephemeral |
+**MinIO note:** default sketch keeps MinIO on the **ground (T3)**. An on-board MinIO sidecar is a possible exception if the team already standardises on an S3 API in Compose — derived data only, never the 5 Hz pose path. Placement is an open question ([09](09-open-questions.md), [00 — Executive](00-executive.md)).
+
## Flight offload: a mirror, not a migration
Because T1 and T3 share the identical layout, offload after landing is:
diff --git a/docs/04-swarm-sync.md b/docs/04-swarm-sync.md
index b8a0730..0efb2a5 100644
--- a/docs/04-swarm-sync.md
+++ b/docs/04-swarm-sync.md
@@ -74,7 +74,7 @@ graph LR
| **DDS multicast** (ROS 2 default) | Works, battle-tested; but discovery storms and tuning pain on lossy wireless meshes are well documented. Keep as fallback since ROS 2 speaks it natively |
| **MQTT** | Needs a broker — a per-drone broker bridge is possible but adds moving parts for no gain over Zenoh |
| **Raw UDP multicast** | **Implemented in the PoC** for pose broadcast (fixed frame, no discovery); no query layer, no reliability — also the documented degraded mode |
-| **MinIO bucket replication** | Wrong tool for the 5 Hz pose path; optional on board for derived datasets and primary on the ground warehouse — not the in-flight bulk path |
+| **MinIO bucket replication** | Keep as a **team option** for bulk derived catch-up if ops already standardise on it; wrong tool for the 5 Hz pose path. Default sketch: MinIO primary on the **ground warehouse**, not on the drone |
## Two sync mechanisms, deliberately separate
@@ -86,7 +86,7 @@ Why SSH-based bulk sync over object-store replication:
- **Identity is already there.** Every drone holds pre-provisioned ed25519 keys and a fixed `known_hosts`/`authorized_keys` set from ground provisioning ([05](05-network-security.md)) — the trust model needs no new machinery.
- **One persistent multiplexed session** (`ControlMaster`) per peer costs almost nothing at idle and survives as a single TCP stream; every transfer rides it without new handshakes.
- **rsync delta transfer is resumable** across link drops — exactly the failure mode of an ad-hoc mesh — and the shared partition layout makes it trivially incremental: same paths, same files, pull only what is missing.
-- **Zero extra services** on the flight-critical node. MinIO remains available where an S3 API is genuinely wanted (ground warehouse, and optionally on board), but the in-flight bulk path does not depend on it.
+- **Zero extra services** on the flight-critical node by default. **MinIO stays first-class on the ground (T3).** On-board MinIO is an exception only if Compose already depends on an S3 API. In-flight bulk path defaults to SSH/rsync; switch to MinIO replication if that is already how the team moves objects.
Partition healing is automatic: replication is pull-based, addressed by partition path, and idempotent (each drone only ever writes its own `drone=` subtree — **no write conflicts by construction**).
diff --git a/docs/06-environments.md b/docs/06-environments.md
index 2d6831f..83ad06c 100644
--- a/docs/06-environments.md
+++ b/docs/06-environments.md
@@ -12,12 +12,12 @@ graph LR
SLICE["T4: data slices"]
end
subgraph fleet [1 — Fleet, in flight]
- D1["drone: Compose data plane
T0 hot + T1 NVMe + T2 MinIO"]
+ D1["drone: Compose data plane
T0 hot + T1 NVMe + T2 peer cache"]
D2["drone …"]
end
subgraph ground [2 — Ground, on-prem]
DOCK["base station docks"]
- DWH["T3 warehouse
object store + Parquet/DuckDB"]
+ DWH["T3 warehouse
MinIO + Parquet/DuckDB"]
K3S["k3s: CI runners, registry mirror,
sim farm, dashboards"]
TRAIN["model training (out of scope)
reads T3, ships weights"]
end
@@ -43,7 +43,7 @@ The permanent installation. This **is** allowed to be a cluster — links are wi
| Component | Runs on | Role |
| --- | --- | --- |
-| **Warehouse (T3)** | Object store (MinIO or equivalent) + Parquet | Every flight of every drone; the system's long-term memory |
+| **Warehouse (T3)** | **MinIO** (already in the stack) + Parquet | Every flight of every drone; the system's long-term memory |
| **Base station docks** | Bare metal | Wired offload + integrity audit + drone provisioning ([03](03-data-platform.md), [05](05-network-security.md)) |
| **Registry mirror** | k3s | In-air-gap container registry + artifact storage; the only software source drones ever see |
| **CI runners** | k3s | Multi-arch builds, tests, scans ([11](11-cicd-delivery.md)) |
diff --git a/docs/08-roadmap.md b/docs/08-roadmap.md
index 0a8420b..37125bc 100644
--- a/docs/08-roadmap.md
+++ b/docs/08-roadmap.md
@@ -9,11 +9,11 @@ graph TD
S1["Stage 1
Dev environment + CI skeleton
Dev Containers, GitLab templates, multi-arch builds"]
S2["Stage 2
Registry and artifacts
images, model weights, schemas, cleanup policies"]
S3["Stage 3
Single-drone data pipeline
ingest → current/ → sealed Parquet → DuckDB"]
- S4["Stage 4
Serving layer
event hook, query API, local MinIO"]
+ S4["Stage 4
Serving layer
event hook, query API"]
S5["Stage 5
Virtual swarm simulation
N drones in Compose, seeded scenarios, CI regression"]
S6["Stage 6
Mesh network and security
WireGuard overlay, PKI provisioning, mTLS"]
- S7["Stage 7
Swarm sync
pose broadcast, detections pub/sub, MinIO replication"]
- S8["Stage 8
Ground warehouse
offload + audit, T3 store, replay tooling"]
+ S7["Stage 7
Swarm sync
pose broadcast, detections pub/sub, bulk pull"]
+ S8["Stage 8
Ground warehouse
offload + audit, MinIO T3, replay tooling"]
S9["Stage 9
Observability
platform metrics as sensor stream, ground dashboards"]
S10["Stage 10
Fleet releases
manifest, mirror, dock delivery, atomic rollback"]
S11["Stage 11
Query standard
GraphQL contract, schema registry, multi-team surface"]
@@ -41,11 +41,11 @@ graph TD
| **1 — Dev environment + CI skeleton** | Dev Containers, GitLab shared templates, multi-arch runner fleet | An engineer builds and tests on day one; ARM64/AMD64 both green | — |
| **2 — Registry & artifacts** | GitLab registry live, model weights + schemas as versioned packages | One artifact store, scanning wired in (Trivy, SonarQube) | 1 |
| **3 — Single-drone data pipeline** | `sensor-ingest` → writer → `current/` → sealed → DuckDB queries on one node | The storage core: rates sustained, compression measured, quotas enforced | 1 |
-| **4 — Serving layer** | Event hook + query API + on-board MinIO | Event-driven consumption; nothing polls | 3 |
+| **4 — Serving layer** | Event hook + query API (SQL gate) | Event-driven consumption; nothing polls | 3 |
| **5 — Virtual swarm** | Simulator, N drones via Compose, seeded scenarios, CI regression gate | Everything after this ships with a test bench | 2, 4 |
| **6 — Mesh & security** | WireGuard overlay, offline CA, provisioning flow, mTLS | Zero-trust fabric exists before any real sync traffic | 1 |
-| **7 — Swarm sync** | Pose broadcast + detections pub/sub + bulk replication over the mesh | Staleness budgets met under simulated loss/partitions | 5, 6 |
-| **8 — Ground warehouse** | Dock offload (mirror + audit), T3 store, replay queries | A full flight round-trips: fly (simulated) → offload → replay | 3 |
+| **7 — Swarm sync** | Pose broadcast + detections pub/sub + bulk partition pull | Staleness budgets met under simulated loss/partitions | 5, 6 |
+| **8 — Ground warehouse** | Dock offload (mirror + audit), **MinIO as T3**, replay queries | A full flight round-trips: fly (simulated) → offload → replay | 3 |
| **9 — Observability** | Platform metrics as sensor stream; ground Prometheus/Grafana/Loki; post-mortem dashboards | Every health question from [07](07-observability.md) answerable | 7, 8 |
| **10 — Fleet releases** | Release manifest, registry mirror, dock delivery, atomic rollback drill | The whole fleet moves as one version, rollback rehearsed | 2, 5 |
| **11 — Query standard** | GraphQL contract over versioned schemas; documentation for other teams | The multi-team integration surface | 7, 8 |
diff --git a/docs/09-open-questions.md b/docs/09-open-questions.md
index 3066c66..2807673 100644
--- a/docs/09-open-questions.md
+++ b/docs/09-open-questions.md
@@ -67,3 +67,16 @@ Sub-250 g class units cannot run the full stack (no GPU, minimal CPU/storage).
The observability path now scans only the most recent flights ([ADR-0009](adr/ADR-0009-bounded-lake-scans.md)), but old `flight=` partitions still accumulate on T1 disk after offload to T3.
*Proposal:* a scheduled prune of T1 partitions whose flights are confirmed present in the T3 warehouse (offload as the retention gate), configurable by age and free-space watermark. On the drone the same policy is bounded by the NVMe quota ladder ([03](03-data-platform.md)); in the sim environment it is a ground CronJob alongside the offload job.
+
+## 12 — MinIO placement (already in the stack)
+
+Exact how MinIO is used today was not fully specified. It should not be ripped out.
+
+*Proposal (default):*
+
+- **Ground warehouse (T3):** primary MinIO home — offload target and long-term object API.
+- **On the drone:** default **off** — local Parquet + DuckDB cover the hot path; an object store competes with flight-critical CPU/RAM.
+- **Exception:** on-board MinIO allowed if Compose already depends on an S3 API — derived datasets only, never 5 Hz pose.
+- **Peer bulk catch-up:** prefer sealed-partition pull (SSH/rsync); use MinIO replication only if that is already the ops standard.
+
+*Settle with the team:* one short diagram of today's MinIO topology (buckets, clients, what syncs). Until then, treat A7 in [01](01-problem-statement.md) as the working assumption. Summary table: [00 — Executive](00-executive.md).
diff --git a/docs/12-design-journey.md b/docs/12-design-journey.md
index 2ce6da4..650ce9d 100644
--- a/docs/12-design-journey.md
+++ b/docs/12-design-journey.md
@@ -144,10 +144,13 @@ gives redundancy and a way to cross-check later. On the ground, when the fleet
returns, the same path unifies every unit's data into a
[local warehouse](06-environments.md). The warehouse is read-mostly for
analytics, so transaction contention is not a concern, which opens a
-DuckDB / DuckLake approach with MinIO underneath, the
+DuckDB / DuckLake approach with **MinIO underneath on the ground (T3)** — MinIO
+is already in the stack, so the warehouse leans on it rather than inventing a
+second object store — the
[same storage model on both ends](adr/ADR-0002-one-storage-format.md). One
uniform structure is what lets an analyst trust a single picture even when a
-unit's data has a gap.
+unit's data has a gap. On-board MinIO stays an open exception, not the default
+([00 — Executive](00-executive.md)).
> **Read the code**
> - [`infra/terraform/ground/main.tf`](https://git.produktor.io/eSlider/swarm-house/src/branch/main/infra/terraform/ground/main.tf#L124-L160) — the post-flight T1 to T3 offload CronJob