Skip to main content

Cheatsheet

Daily ERun commands and common patterns.

Lifecycle​

# Universal entry point — runs init or open depending on state.
erun

# Explicit forms.
erun init <tenant> <env>           # set up a new tenant or env
erun open <tenant> <env>           # attach to an existing env
erun delete <tenant> <env>         # tear down

# Always safe to preview.
<any command> --dry-run            # show every action without executing

Building and shipping​

# Agent env workflow.
erun build                          # build the current context with a snapshot tag
erun push                           # rebuild + push to registry
erun deploy                         # build → push → helm upgrade

# Combined.
erun build --deploy                 # build then deploy in one shot
erun build --release                # stable tag — typically run by CI

# Runtime env workflow.
erun deploy --version 1.0.77 --tenant t --environment prod \
            <component>             # roll out a pre-built version

Inspecting​

erun list                           # tenants · envs · effective target
erun list cloud                     # managed cloud contexts only
erun doctor                         # diagnose local config + runtime pod
erun version                        # erun's build version (+ the project's, when in one)
erun mcp tools                      # what the env's MCP edge can do
erun mcp call --tool list           # one typed call against the env

Editing and attaching​

erun open                           # shell into the env
erun open --vscode                  # launch VS Code Remote-SSH
erun open --intellij                # launch IntelliJ Gateway
erun open --no-shell                # print kubectl/cd commands for scripting

MCP for agents​

# From the desktop, port-forward is published automatically.
cat <UserConfigDir>/erun/portforward/mcp/<tenant>/<env>.json

# Wire your agent client:
claude --mcp-config <that-file>
# or: codex --mcp-server-url http://127.0.0.1:<port>/mcp

Common patterns​

Spin up a sibling env for peer review​

git worktree add ~/code/myapp-review feature-from-peer
erun init myapp review --project-root ~/code/myapp-review
erun open myapp review

Hotfix while keeping the feature env alive​

git worktree add ~/code/myapp-hotfix hotfix/urgent
erun init myapp prod-local --project-root ~/code/myapp-hotfix \
                            --kubernetes-context erun-prod
erun open myapp prod-local
# inside the pod:
erun build --release
erun deploy <component> --tenant myapp --environment prod --version 1.0.77

Run integration tests against the env's own stack​

erun open myapp local
# inside the pod:
./test/integration.sh

Switch the env's registry to ECR​

erun init myapp rihards-dev \
  --container-registry 020362606330.dkr.ecr.eu-west-2.amazonaws.com \
  --kubernetes-context erun-004-020362606330-eu-west-2

Override a build step with a project script​

Drop build.sh (or push.sh, deploy.sh, release.sh) at the project root or in any module subtree. ERun finds it and runs it instead of the built-in command. See Conventions.

Read this when something's wrong​

  • Troubleshooting — common errors and how to diagnose.
  • erun doctor — first command to run when anything's unclear.
  • <command> --dry-run — preview before you commit.