Choose separate repositories when different people must have different read access, because Git hosting grants access to a repository as a whole. Choose a monorepo when everyone who can read part of it can read all of it, and use code owners, rulesets and scoped scanning to manage review and risk.
What a monorepo gives you
One place for shared libraries, one set of branch rules, atomic changes across services, and one dependency policy. Security teams like the single view of what is deployed. Developers like not juggling many pull requests for one change.
What it cannot give you
Read access is all or nothing at the repository level. Tools such as sparse checkout change what is in your working directory, not what you are allowed to see; read why sparse checkout is not access control. Code owners route review of changes, not reading.
Questions to ask
- Who must not read this code? Contractors, an acquired team, a regulated workload, customer specific code. If the answer is anyone, split it out.
- Does this code hold secrets or customer data? It should not in either layout, but a separate repository limits the blast radius of a mistake.
- Do release cadences differ sharply? Different tag and release rules are easier in separate repositories.
- Who approves changes? If ownership is by directory, CODEOWNERS can express it. See CODEOWNERS for a monorepo.
- Can your tooling handle the size? Scanners and CI need path filters to avoid scanning everything on every change.
Running a monorepo securely
- Set a baseline ruleset for the whole repository, with stricter rules for release branches.
- Anchor CODEOWNERS paths and protect the file.
- Scope CI jobs and required checks by changed path, but make sure a required check cannot be skipped by touching no files.
- Produce SBOMs per deployable unit rather than one giant file; see one SBOM or many for a monorepo.
- Keep a list of every package manifest location so nothing is left unscanned.
Running many repositories securely
The risk flips to drift. Rules differ between repositories, and some get no review at all. Use organization wide rulesets where your plan allows, templates for new repositories, and an inventory of every repository with an owner.
Try it yourself
Click through it at your own pace, or open it full screen. Look for how one inventory can span many components.
Quick check
Can I give a team access to one folder of a monorepo?
Standard repository permissions do not work per folder. Use a separate repository for code that must be restricted.
Is a monorepo less secure than many repositories?
Not inherently. It concentrates access decisions in one place, so it needs deliberate review and scanning rules.
Safeguard SBOM and dependency scanning can cover many manifests across a repository, and the free scan at gold.safeguard.sh/scan lets you try it first.
Last reviewed: 19 October 2026.
