Source: https://seerepo.com/compare/flannel-io/flannel/vs/istio/istio
Markdown source: https://seerepo.com/compare/flannel-io/flannel/vs/istio/istio.md
Description: flannel and istio share 3 technologies: net/http, k8s.io/klog/v2, and github.com/containernetworking/plugins. Both are written in Go.

# flannel vs istio

flannel and istio share 3 technologies: net/http, k8s.io/klog/v2, and github.com/containernetworking/plugins. Both are written in Go.

- [flannel-io/flannel](https://seerepo.com/r/flannel-io/flannel): flannel is a network fabric for containers, designed for Kubernetes
- [istio/istio](https://seerepo.com/r/istio/istio): Connect, secure, control, and observe services.

## What they share and what sets them apart

- In common: net/http, k8s.io/klog/v2, github.com/containernetworking/plugins
- Only in flannel: etcd, github.com/Microsoft/hcsshim, github.com/coreos/go-systemd/v22, github.com/tencentcloud/tencentcloud-sdk-go/tencentcloud/common
- Only in istio: Gorilla, github.com/hashicorp/golang-lru/v2, sigs.k8s.io/controller-runtime, k8s.io/apiserver, github.com/cheggaaa/pb/v3, golang.org/x/oauth2, github.com/coreos/go-oidc/v3, github.com/go-jose/go-jose/v4, github.com/lestrrat-go/jwx, google-auth, sigs.k8s.io/gateway-api-inference-extension, github.com/agentgateway/agentgateway/api, sigs.k8s.io/gateway-api, OpenTelemetry, Prometheus, go.uber.org/zap, github.com/containernetworking/cni, cloud.google.com/go/compute/metadata, github.com/openshift/api, github.com/go-logr/logr, github.com/grpc-ecosystem/go-grpc-prometheus, go.opentelemetry.io/otel/exporters/prometheus, gopkg.in/natefinch/lumberjack.v2

## Side by side

| | flannel | istio |
|---|---|---|
| Size | 19,318 lines written, 68 code files | 612,149 lines written, 932 code files |
| Who writes it | 1.8% of its commits signed by AI. With GitHub Copilot and Claude Code | 0.1% of its commits signed by AI. With Claude Code, GitHub Copilot, and Cursor |
| Activity | Last push November 9, 2026, 1,325 commits, 9,568 stars | Last push November 14, 2026, 26,605 commits, 38,505 stars |
| Tests | 38 test files. 41.2% of its code files have a test that imports them | 1,098 test files. 76.8% of its code files have a test that imports them |

- Size: Lines written by people and agents, without generated ones; code files, without tests.
- Who writes it: A commit counts as AI's when it carries its signature: a Co-Authored-By line, its author name or the merge of its branch.
- Activity: From GitHub and its history, on the day SeeRepo read it.
- Tests: The files that test the code, and the share of code files a test imports.

## Frequently asked questions

### Which is bigger, flannel or istio?

istio, with 612,149 lines written; flannel has 19,318.

The proof: [istio/istio's code at commit 8a9fad9](https://github.com/istio/istio/tree/8a9fad9e460448451d287ba37328062e9440f5c4)

### Which has more GitHub stars, flannel or istio?

istio, with 38,505 stars; flannel has 9,568.

The proof: [istio/istio on GitHub](https://github.com/istio/istio)

### Which has more tests, flannel or istio?

istio, with 1,098 test files; flannel has 38.

The proof: [istio/istio's code at commit 8a9fad9](https://github.com/istio/istio/tree/8a9fad9e460448451d287ba37328062e9440f5c4)

### Which was updated more recently, flannel or istio?

istio: its last push was on November 14, 2026, and flannel's on November 9, 2026.

The proof: [istio/istio's commits on GitHub](https://github.com/istio/istio/commits)

### Which has more commits signed by AI, flannel or istio?

flannel: an AI signed 1.8% of its commits, with GitHub Copilot and Claude Code; in istio, 0.1%.

The proof: [the commits each tool signed in flannel-io/flannel](https://seerepo.com/r/flannel-io/flannel/ai)

## Sources

- flannel-io/flannel: Read on November 14, 2026, at commit dc074a9 (https://github.com/flannel-io/flannel/tree/dc074a93121c406313b7f6c2607d9ad102b6d24e)
- istio/istio: Read on November 14, 2026, at commit 8a9fad9 (https://github.com/istio/istio/tree/8a9fad9e460448451d287ba37328062e9440f5c4)

## What is your repo built with?

Any public repo, with no account: https://seerepo.com/r/owner/repo/built, with the owner and name it has on GitHub.