Downstream Integration — Dependency Chain and Responsibilities#

Four-Layer Dependency Chain#

Layer 1: MADDENING          (open source, LGPL, general-purpose framework)
    ↓
Layer 2: MIME                (open source, LGPL, microrobotics physics engine)
    ↓
Layer 3: MICROBOTICA         (open source, LGPL, research simulator)
    ↓
Layer 4: [Commercial Product] (regulated, CE-marked, built by commercial entity)

Layer

Status

Regulatory Obligation

MADDENING

Open-source research tool

None (provides SOUP documentation voluntarily)

MIME

Open-source research tool

None (provides SOUP documentation voluntarily)

MICROBOTICA

Open-source research tool

None (provides SOUP documentation voluntarily)

Commercial Product

Regulated medical device

Full EU MDR manufacturer obligations

Per-Layer Responsibility Details#

Layer 1: MADDENING#

Role: General-purpose JAX-based multiphysics simulation framework.

Provides:

  • Core simulation infrastructure: graph management, JIT compilation, multi-rate scheduling, adaptive timestepping

  • Physics node library: heat diffusion, rigid body dynamics, spring-damper, LBM fluid

  • Neural surrogate framework: training, validation, architecture library

  • Compliance infrastructure: NodeMeta, anomaly registry, verification benchmark registry, @stability decorator, HealthCheckNode

  • SOUP documentation package (docs/validation/soup_package.md)

Does NOT provide:

  • Clinical claims or intended clinical use

  • Domain-specific physics for microrobotics (CSF flow, Brownian motion, magnetic actuation)

  • Risk management file (ISO 14971) — only hazard_hints for downstream risk analysis

  • QMS, clinical evaluation, or post-market surveillance

SOUP classification: When used in a regulated product, MADDENING is IEC 62304 SOUP. Its safety class is determined by the downstream manufacturer based on the context of use.

Layer 2: MIME (MIcrorobotics Multiphysics Engine)#

Role: Domain-specific physics engine for microrobot simulation, built on MADDENING.

Provides:

  • CSF flow simulation nodes (wrapping or extending LBMPipeNode)

  • Magnetic field and actuation models

  • Particle dynamics for microrobots (Brownian, drag, contact)

  • Domain-specific HealthCheckNode configurations (e.g., CSF density bounds, velocity limits)

  • Own SOUP documentation, anomaly registry, and verification benchmarks (using MIME- prefix)

Inherits from MADDENING:

  • Compliance schema types (NodeMeta, AnomalyRecord, etc.) via maddening.compliance

  • Anomaly registry validator CLI

  • @verification_benchmark and @stability decorators

  • HealthCheckNode base class

SOUP classification: When used in a regulated product, MIME is IEC 62304 SOUP. MADDENING is MIME’s own SOUP dependency (SOUP-of-SOUP).

Layer 3: MICROBOTICA#

Role: Open-source research simulator for microrobot-assisted drug delivery in CSF.

Provides:

  • Pre-configured simulation scenarios for cerebrospinal fluid geometries

  • Visualization and analysis tools for researchers

  • Training data pipelines for reinforcement learning research

  • Own SOUP documentation, anomaly registry, and verification benchmarks (using MICROBOTICA- or MBOT- prefix)

Inherits from MIME: All MIME compliance infrastructure, plus MIME-specific physics and verification evidence.

SOUP classification: When used in a regulated product, MICROBOTICA is IEC 62304 SOUP.

Layer 4: Commercial Product#

Role: CE-marked medical device software built by a downstream commercial entity.

This is the ONLY layer subject to EU MDR. The commercial entity is the EU MDR manufacturer (Article 2(30)).

Commercial Responsibility Statement#

The Layer 4 commercial entity is the EU MDR manufacturer (Article 2(30)) and is solely responsible for all regulatory obligations, including but not limited to:

  • Establishing and maintaining an ISO 13485 QMS certified by a Notified Body

  • Performing the conformity assessment procedure appropriate to the device class (Class IIb: Annex IX or Annex X+XI; Class III: Annex IX or Annex X+XI with full technical file review)

  • Engaging and satisfying the Notified Body for initial conformity assessment and annual surveillance audits

  • Building and maintaining the clinical evaluation report (CER) with sufficient clinical evidence

  • Operating post-market surveillance including PSUR (annual for Class III), vigilance reporting, and PMCF studies

  • Bearing manufacturer liability for the device placed on the EU market

  • Performing SOUP assessment of all open-source layers (MADDENING, MIME, MICROBOTICA) per IEC 62304 Clause 5.3.3/5.3.4

  • Maintaining risk management file (ISO 14971) incorporating SOUP failure modes

MADDENING provides SOUP documentation to support the commercial entity’s regulatory obligations. This provision is voluntary and does not make MADDENING subject to EU MDR or IEC 62304.

Classification-by-Use-Mode Analysis#

The EU MDR classification of the Layer 4 commercial product depends on its intended use:

Use Mode

Classification

Rationale

Research / pre-clinical simulation

Not a medical device

No clinical decision-making; general-purpose tool (MDCG 2019-11 §3.2)

Treatment planning (pre-operative)

Class IIa

Software providing information used to make decisions with diagnosis or treatment purposes (Rule 11, Annex VIII); non-immediate clinical context

Intraoperative digital twin

Class IIb minimum, likely Class III

Real-time surgical decision support; erroneous output during live procedure in CSF spaces adjacent to striatum/substantia nigra could cause irreversible neurological harm (Rule 11(b))

RL policy generation for microrobot control

Class III

Software directly informs an active control loop for a device operating in the CNS; failure could result in death or serious injury (Rule 11(b), Rule 22)

The MADDENING documentation architecture is designed to support the most demanding classification (Class III / IEC 62304 Class C) so that less demanding use cases are automatically covered.

Commercial Boundary Documentation#

What MADDENING provides to the commercial entity#

  1. SOUP Package (docs/validation/soup_package.md): Software identification, functional description, known anomalies, verification evidence, lifecycle activities, configuration management, anomaly management policy, dependency list

  2. Known Anomalies Registry (docs/validation/known_anomalies.yaml): Machine-readable, versioned, validated by CI

  3. Verification Evidence: Registered benchmarks with analytical solutions, convergence studies, and regression tests

  4. Hazard Hints: Per-node qualitative risk information for integration into the manufacturer’s ISO 14971 risk management file

  5. Algorithm Guides: Per-node documentation of governing equations, discretization, assumptions, limitations, and validated regimes — with CI-validated bibliography citations (docs/bibliography.bib) and CI-validated implementation-to-code mappings

  6. HealthCheckNode: Configurable execution-layer fault detection (NaN/Inf, bounds, moment checks) for use in downstream safety monitoring

  7. Compliance Schema Types: Importable Python types (NodeMeta, AnomalyRecord, etc.) for downstream libraries to use and extend

  8. SBOM: CycloneDX-format software bill of materials attached to each release

What MADDENING does NOT provide#

  • Clinical safety assessment

  • Intended use for any specific clinical application

  • Risk management file (ISO 14971)

  • Clinical evaluation report (CER)

  • Post-market surveillance plan

  • QMS documentation (ISO 13485)

  • Notified Body relationship

  • End-user training materials for clinical use

  • Cybersecurity risk assessment for the deployed product (MADDENING assumes trusted inputs; see docs/regulatory/intended_use.md)

LGPL Replaceability#

MADDENING is licensed under LGPL-3.0-or-later. The LGPL “replaceability” obligation is satisfied via Python’s module system: the end user can replace the maddening package with a modified version by installing it into the same Python environment, with no special linking or build steps required. The commercial entity should document this replaceability mechanism in their technical file.