Comparison
GitHub Copilot Coding Agent: Hosted coding agent vs. self-hosted overnight desk.
GitHub Copilot Coding Agent is a hosted agent that opens pull requests from a GitHub-managed identity. Driftlock is a self-hosted watcher that opens pull requests from the customer’s own CI identity, runs inside the customer’s VPC, and only lands diffs that the customer’s reviewers approve. Where Copilot Coding Agent optimises for breadth (any repo, any task), Driftlock optimises for bounded overnight signals: a CI failure, a Dependabot alert, a CVE, an on-call page — each of which becomes one signed pull request linked to its trigger.
Posture
Driftlock runs self-hosted in your VPC; no third-party LLM is ever called at the test step.
Identity
Commits sign with your cosign key in your KMS or HSM. Keys rotate on your schedule.
Audit
Seven per-PR columns — alert id, sandbox run hash, SBOM hash, approver chain, signature, diff bytes, triage verdict — replayable on your storage tier.
What they do
GitHub Copilot Coding Agent in one paragraph.
GitHub Copilot Coding Agent is a hosted agent that reads a written prompt or GitHub issue and opens a pull request against a repository in the user’s GitHub organisation; the unit of work is a free-form task description, and the agent runs on GitHub-managed infrastructure as a GitHub App.
Where Driftlock differs
Eight dimensions where the posture diverges.
Each row names one axis — autonomy, hosting, audit, signing, SBOM, sandbox, monorepo scale, CI touch — and states both sides on that axis. No feature checklist, no marketing re-framing.
Axis · autonomy scope
Them
Accepts a free-form written prompt or issue body and decides what to build or fix; no signal surface is required.
Driftlock
Acts only on overnight signals already in your stack (CI failure, Dependabot alert, CVE, on-call page); no goal, no run.
Axis · self-hosting
Them
Runs on GitHub-managed infrastructure inside the GitHub tenant.
Driftlock
Runs as a single Helm + Terraform deployment inside your VPC, behind your egress policy.
Axis · audit trail
Them
Records the prompt and the resulting diff on the GitHub-managed control plane; replay requires GitHub.
Driftlock
Records seven per-PR columns (alert id, sandbox run hash, SBOM hash, approver chain, signature, diff bytes, triage verdict) replayable on your storage tier without a Driftlock-managed control plane.
Axis · commit-signing
Them
Commits land from a GitHub App identity; commit signing depends on repository settings and is not Driftlock-grade.
Driftlock
Commits sign with your cosign key kept in your KMS or HSM; key rotation happens on your schedule.
Axis · SBOM
Them
Does not emit a per-PR SBOM as a first-class artifact; dependency review is delegated to GitHub-native tooling.
Driftlock
Emits an SBOM hash per PR, recorded alongside the diff and the signature so reviewers can diff two SBOMs without re-running the build.
Axis · sandbox execution
Them
Runs in a GitHub-managed sandbox; the customer does not control the build cache or the toolchain pinning.
Driftlock
Runs inside a hermetic sandbox that mounts the existing monorepo’s toolchain and test cache, and replays the original regression before opening the PR.
Axis · monorepo scale
Them
Designed for breadth across many repositories; large monorepos work but the sandbox does not share the team’s build cache.
Driftlock
Built for one large monorepo per deployment; the sandbox mounts the monorepo’s existing caches so a CI rerun is bounded by what CI itself already proves.
Axis · CI touch
Them
Calls into CI opportunistically; the agent can wait for CI but does not feed results back into a deterministic loop.
Driftlock
Treats CI as the source of truth — the agent reads CI failures as triggers and reruns the original regression inside the sandbox before opening the PR.
8 axes · posture-level · no feature checklist
FAQ
Questions comparison-stage buyers ask.
See it on your stack
Compare on a real monorepo, not a slide deck.
The architecture page names the four signal sources the watcher reads; the governance page enumerates the seven per-PR columns a regulator replays. Run the comparison against one of your real monorepos on a ten-day scoped trial — you'll see the diffs Driftlock ships and the audit trail your reviewers sign.