Argo CD

Flux

fluxcd/flux2

Popular

CNCF-graduated GitOps toolkit that reconciles Kubernetes from Git, OCI artifacts and Helm sources.

Argo Rollouts

argoproj/argo-rollouts

Kubernetes controller adding blue-green and canary deployments with metric-based automated analysis.

Kargo

akuity/kargo

Rising

Promotes releases through environments (dev, staging, prod) on top of Argo CD; from the Argo creators.

Flagger

fluxcd/flagger

Progressive delivery operator automating canary, A/B and blue-green releases with Flux or a service mesh.

Octopus Deploy

octopus.com

Release and deployment automation for multi-environment and multi-tenant apps, strong in .NET shops.

Harness

harness.io

Commercial software delivery platform spanning CD, CI, feature flags and cloud cost management.

Spinnaker

spinnaker/spinnaker

Legacy

Netflix-born multi-cloud CD platform; powerful but heavy, and largely superseded by GitOps tools.

LaunchDarkly

launchdarkly.com

Popular

Leading commercial feature-flag and experimentation platform for controlled, gradual releases.

Unleash

Unleash/unleash

Open-source, self-hostable feature flag platform with gradual rollouts and SDKs for most languages.