とすると、go.modなどに書かれた依存パッケージが $GOPATH/pkg/mod/ へキャッシュされます。このディレクトリをCircle CIの save_cache に指定すれば良さそうです。 例: version: 2 defaults: &defaults jobs: setup-build: docker: - image: golang:stretch working_directory: /workspace environment: GOPATH: / GOCACHE: /.cache/go-build GO111MODULE: "on" steps: - run: go env - checkout - restore_cache: keys: - go-module-cache-v1-{{ checksum "/workspace/go.sum" }} - go-mo
![go modulesとCircle CIのキャッシュを使ってビルド&テストを高速化する - Qiita](https://cdn-ak-scissors.b.st-hatena.com/image/square/e6de7c47a3f36a595393a838427c76d8b25624ab/height=288;version=1;width=512/https%3A%2F%2Fqiita-user-contents.imgix.net%2Fhttps%253A%252F%252Fcdn.qiita.com%252Fassets%252Fpublic%252Farticle-ogp-background-412672c5f0600ab9a64263b751f1bc81.png%3Fixlib%3Drb-4.0.0%26w%3D1200%26mark64%3DaHR0cHM6Ly9xaWl0YS11c2VyLWNvbnRlbnRzLmltZ2l4Lm5ldC9-dGV4dD9peGxpYj1yYi00LjAuMCZ3PTk3MiZoPTM3OCZ0eHQ9Z28lMjBtb2R1bGVzJUUzJTgxJUE4Q2lyY2xlJTIwQ0klRTMlODElQUUlRTMlODIlQUQlRTMlODMlQTMlRTMlODMlODMlRTMlODIlQjclRTMlODMlQTUlRTMlODIlOTIlRTQlQkQlQkYlRTMlODElQTMlRTMlODElQTYlRTMlODMlOTMlRTMlODMlQUIlRTMlODMlODklRUYlQkMlODYlRTMlODMlODYlRTMlODIlQjklRTMlODMlODglRTMlODIlOTIlRTklQUIlOTglRTklODAlOUYlRTUlOEMlOTYlRTMlODElOTklRTMlODIlOEImdHh0LWFsaWduPWxlZnQlMkN0b3AmdHh0LWNvbG9yPSUyMzIxMjEyMSZ0eHQtZm9udD1IaXJhZ2lubyUyMFNhbnMlMjBXNiZ0eHQtc2l6ZT01NiZzPTk0OTNiZTBkODBiZGM1NWRkZjE4Njk1MGNhOWI5NWY1%26mark-x%3D142%26mark-y%3D57%26blend64%3DaHR0cHM6Ly9xaWl0YS11c2VyLWNvbnRlbnRzLmltZ2l4Lm5ldC9-dGV4dD9peGxpYj1yYi00LjAuMCZoPTc2Jnc9NzcwJnR4dD0lNDBhdG90dG8mdHh0LWNvbG9yPSUyMzIxMjEyMSZ0eHQtZm9udD1IaXJhZ2lubyUyMFNhbnMlMjBXNiZ0eHQtc2l6ZT0zNiZ0eHQtYWxpZ249bGVmdCUyQ3RvcCZzPTE0MmQ4NzZjYTYwMDYwZTk5N2JlZGVjNGYwYmVjYWEz%26blend-x%3D142%26blend-y%3D436%26blend-mode%3Dnormal%26txt64%3DaW4gR1JPT1ZFIFjmoKrlvI_kvJrnpL4%26txt-width%3D770%26txt-clip%3Dend%252Cellipsis%26txt-color%3D%2523212121%26txt-font%3DHiragino%2520Sans%2520W6%26txt-size%3D36%26txt-x%3D156%26txt-y%3D536%26s%3D9e18dae6b77f1bb519235542f809a098)