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Core Concepts

This page explains the key building blocks of Bailo and how they relate to each other. Understanding these concepts will help you navigate the platform and make the most of its features.

Common questions this page answers:

  • What is a model card?
  • What is the difference between a release and a model?
  • What roles exist in Bailo?
  • How does the review process work?

Entry types

Bailo organises content into four entry types, each serving a different purpose:

  • Model - A machine learning model with full lifecycle management - model card, releases, access control, and reviews
  • Data Card - Documentation for a dataset, tracking its provenance, storage, and relationship to models
  • Mirrored Model - A read-only copy of a model from another Bailo instance or external source
  • Untrusted Model - A model flagged for additional scrutiny, with restricted capabilities

Some Entry types must be enabled by your Bailo administrator before they can be used.

The lifecycle of a model

A model follows a structured lifecycle from creation through review to consumer access:

Create Model → Select Schema → Fill In Model Card → Add Collaborators
  → Upload Files / Images → Create Release → Review & Approval
  → Consumers Request Access → Download / Pull

1. Model

A Model is the top-level container. It has a name, description, visibility (public or private), and a list of collaborators. Creating a model is the first step.

2. Schema

A Schema defines the structure of a model card - what questions must be answered about a model. Schemas are created by administrators and selected when setting up a model. There are two kinds:

  • Model Card schemas define the metadata form for models
  • Access Request schemas define the form users fill in when requesting access

3. Model Card

The Model Card is the structured documentation attached to a model. It captures information like intended use, training methodology, known limitations, and performance metrics. The questions come from the selected schema.

Model cards are versioned - each edit creates a new version, and you can view the history to see how documentation has evolved.

4. Release

A Release is a versioned snapshot of a model at a point in time. Releases use semantic versioning (e.g. 1.0.0, 1.1.0, 2.0.0) and include:

  • A reference to a specific model card version
  • Attached files (model weights, configuration files, etc.)
  • Attached container images (e.g. Docker images)
  • Release notes

Creating a release triggers the review process.

5. Review

When a release or access request is created, it enters a Review process. Reviewers assigned to the model evaluate the submission and either approve it or request changes. Reviews are driven by Review Roles - named roles like "Model Technical Reviewer" or "Model Senior Responsible Officer" that an administrator configures.

A release is only approved when all required review roles have given their approval.

6. Access Request

To download files or pull container images from a model, users must create an Access Request. This submission goes through its own review process. Once approved, the user gains the permissions specified in the request.

Some models may have ungoverned access enabled, which allows any user to download files without going through the access request process.

Roles and permissions

Bailo uses two complementary role systems to control access and governance.

System Roles

These are assigned per-model and control what actions a user can take:

  • Owner - Full control: edit model, manage collaborators, create releases, delete the model
  • Contributor - Edit the model card, upload files and images, create releases
  • Consumer - Download files and pull images (requires an approved access request, unless ungoverned access is on)

Review roles

These are created by administrators and attached to schemas. When a model uses a schema with review roles, those roles must be assigned to specific people who will review releases and access requests. Common examples include:

  • Model Technical Reviewer (MTR) - reviews the technical quality of the model
  • Model Senior Responsible Officer (MSRO) - reviews governance and compliance aspects

For a full reference, see Roles & Permissions.

Entry roles

The collective term for all system roles and review roles.

Visibility

Model visibility controls who can discover and browse a model:

  • Public models appear in the Marketplace and can be found by any user
  • Private models are only visible to users who have been explicitly added as collaborators

Even for public models, downloading artefacts typically requires an approved access request.

Security scanning

Depending on configuration, Bailo automatically scans uploaded files and container images for security issues:

  • Files are scanned by ClamAV (malware detection) and ModelScan (serialisation attack detection)
  • Container images are scanned by Trivy (vulnerability detection with CVE reporting)

Scan results are displayed alongside each file and image, with severity ratings.

Your Bailo administrator may change what scanners are enabled and used.

Federation

Federation allows multiple Bailo instances to share models across organisational boundaries.

Bailo instances can be connected through Federation, allowing models from one instance to appear in another. This is useful for organisations with multiple deployments or for integrating with external model repositories like HuggingFace Hub.

Federated models appear as Mirrored Models - read-only entries that stay in sync with their source.

What's Next?

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