{{ result.summary.heading }}
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Use the DNS-safe service name other Compose services should call.
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Published images produce an image key; local builds produce a build block with context and Dockerfile.
Example: ghcr.io/example/orders-api:2026.05 or nginx:1.27-alpine.
{{ fieldErrors.image_name }}
Use a relative folder that contains the Dockerfile or build source.
{{ fieldErrors.build_context }}
Leave as Dockerfile unless your context uses a named Dockerfile.
Use 127.0.0.1:host:container when a dev service should not bind publicly.
Keep non-secret defaults here; the generator can produce an .env example for sensitive values.
Reference secret-like values from .env when the Compose file should be safe to commit.
Examples: ./app:/usr/src/app:ro or app_data:/var/lib/app.
Choose how the Docker daemon should restart the container after failures or host restarts.
Use HTTP for web services, command for stateful services, or none when the image already owns readiness.
The default uses localhost and the container port from the port mapping when possible.
Example: pg_isready -U $${POSTGRES_USER:-postgres} -d $${POSTGRES_DB:-postgres}.
Leave blank to use Docker Compose's implicit default network.
Optional. Use only when another local integration expects a fixed container name.
Use only when the image default command needs to be replaced.
Optional .env-style files read by Compose for this service.
Optional dependency gates for stacks that include other services in the same Compose file.
Optional metadata for routers, monitoring, or local inventory.
Use a non-root user only when the image and mounted paths support it.
Set only when the runtime command must start from a specific path.
Optional profiles for services that should run only in selected Compose workflows.
{{ result.composeYaml || result.emptyText }}
{{ result.envExample || result.emptyEnvText }}
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Docker Compose turns a container service plan into YAML that the Docker Compose CLI can start, stop, inspect, and tear down as one application unit. A Compose service usually needs a runtime source, network posture, configuration values, storage mounts, readiness behavior, and recovery policy. Getting those choices into a readable draft early helps prevent small deployment mistakes such as an unpinned image, a public port bind, or a secret copied into version control.

A single-service Compose file is often the first artifact written for an API, worker, reverse proxy, database sidecar, or local development dependency. The important question is not only whether the YAML is valid. The draft should also make clear where the image comes from, which port is exposed on the host, which values belong in the environment, whether the service has a healthcheck, and what will happen after a crash or host restart.

Compose service draft flow from service name through runtime source, configuration, YAML, and review checks

Compose is also easy to overread. A generated file can describe intent, but it cannot prove that an image tag exists, the target port is listening, a mounted path has the right permissions, or a healthcheck command succeeds inside the container. Treat the first draft as a structured starting point, then verify it with the real project files, secrets policy, and a test run.

Technical Details:

A Compose file is a YAML document whose top-level services map defines the containers that make up an application. Each service can pull an existing image or build one from source, publish ports to the host, receive environment values, mount host paths or named volumes, join networks, expose labels, and define lifecycle behavior such as restart policy and health reporting.

The generator emits a Compose-style service draft rather than a full multi-service platform model. That focus keeps the output readable for handoff: one service key, one runtime source, optional mounts and dependencies, a readiness probe when selected, and supporting top-level network or volume declarations when the inputs require them. It does not run Docker, inspect images, or validate host-side file paths.

Rule Core:

The generated YAML follows a direct mapping from inputs to Compose entries. Optional sections appear only when corresponding values are present or a selected mode needs them.

Input area YAML entry Behavior Review cue
Service name services.<name> Creates the service key used by Compose DNS and by sibling services. Use a stable, DNS-safe name such as api, worker, or redis.
Runtime source image or build Image mode writes an image reference; build mode writes context and an optional Dockerfile path. Pin image tags or digests when repeatable pulls matter.
Ports ports Accepts host-to-container mappings, host-IP bindings, container-only ports, and protocol suffixes such as /udp. Use a host IP such as 127.0.0.1 when the service should stay local to the host.
Environment variables environment and optional .env example Parses KEY=value rows and can replace secret-looking values with required environment references. Review keys containing password, token, secret, credential, database URL, or auth wording before committing.
Volumes volumes plus top-level named volumes Bind mounts are passed through; named volume sources are collected into a top-level declaration. Add :ro to host binds when the container only needs read access.
Healthcheck healthcheck HTTP mode writes a shell readiness command using wget or curl; command mode writes the supplied shell command. Confirm the command exists inside the image and checks readiness, not just process startup.
Depends on depends_on Maps words such as healthy, started, or completed to Compose dependency conditions. service_healthy only helps when the dependency has a working healthcheck.

Deployment checks are static review notes. They compare the selected options with common Compose risks and label each row as Pass, Review, Warning, or Info. The label is useful, but the evidence and action text carry the practical meaning.

Check Trigger What to do before handoff
Image pinning Missing tag, digest, or use of :latest. Use a version tag or digest when the same file should pull the same runtime later.
Port binding A published port has no host IP. Decide whether the service should bind all interfaces or only 127.0.0.1.
Secret handling Secret-looking keys are either referenced from environment or kept as literal values. Prefer references for commit-safe drafts and keep the generated example out of shared repos when it contains real values.
Healthcheck No healthcheck, empty target, or HTTP/command readiness probe. Run the stack and confirm the health status changes as expected.
Restart policy no, always, on-failure, or unless-stopped. Match the policy to the workload; long-running services usually need explicit recovery behavior.
Scalability A fixed container_name is present. Use fixed names only when another local integration truly depends on that exact container name.
Bind mounts A host bind appears writable. Make source-code and configuration mounts read-only unless the container must write to them.

Environment precedence is worth checking after generation. Compose treats service-level environment values as stronger than env_file values, so the same key in both places can produce a different container environment than expected. The output gives a useful draft, but the final authority is the rendered configuration from Docker Compose on the host.

Everyday Use & Decision Guide:

Start with the runtime source. Choose Published image when the service already has a registry image such as nginx:1.27-alpine or ghcr.io/example/orders-api:2026.05. Choose Local build context when the Compose file should build from a project directory, then keep the build context relative so the file can move with the repository.

Fill Service name, Ports, Environment variables, and Volumes before touching the advanced panel. A good first pass for a local API might use api, 127.0.0.1:8080:3000, APP_ENV=production, and ./app:/usr/src/app:ro. That gives you a readable service key, a private host bind, clear configuration, and a read-only source mount.

  • Use Secret handling set to Reference secret-like keys from .env when rows such as API_TOKEN=change-me or DATABASE_URL=... should not be committed as literal Compose values.
  • Choose HTTP endpoint for web services with a readiness URL, Shell command for services such as databases, and No Compose healthcheck only when the image or surrounding platform already owns readiness.
  • Use Depends on for sibling services in the same Compose file. Rows such as db:healthy and migrate:completed become long-form dependency conditions.
  • Keep Container name blank unless another local script requires it. Compose project scoping and scaling work better without a fixed container name.
  • Use Profiles for optional workers or debug services that should start only when a profile is selected.

The main stop-and-verify surface is Deployment Checks. A Review row for port binding means the service may listen beyond localhost. A Warning row for secret handling means a secret-looking value stayed literal. A Review row for missing healthcheck does not prove the service is unsafe, but it is a prompt to decide where readiness is verified.

Do not treat generated YAML as a release artifact until it has passed a real Compose check. Copy Compose YAML, run the stack in a safe project directory, inspect docker compose config, then confirm logs, health state, port exposure, mounts, and environment values match the intended service.

Step-by-Step Guide:

Build the service draft from identity to runtime to review notes, then use the generated YAML only after input errors are clear.

  1. Enter Service name. Confirm the summary primary value shows the intended service key rather than an accidental placeholder.
  2. Choose Runtime source. In image mode, fill Image and check whether Deployment Checks flags an unpinned or :latest reference. In build mode, fill Build context and adjust Dockerfile path only when the file is not named Dockerfile.
  3. Add Ports. Use one mapping per line and look for a Port binding review row when a host port has no host IP.
  4. Add Environment variables and choose Secret handling. If a red validation message says an environment key must use shell variable syntax, fix the key before copying Compose YAML.
  5. Add Volumes. Open Service Blueprint and confirm the volume count and named-volume count match the intended mounts.
  6. Choose Restart policy and Healthcheck. For HTTP mode, check that Healthcheck URL points to a container-local endpoint such as http://localhost:3000/health.
  7. Fill Network name only when you want an explicit named bridge network. If you clear the field, verify the Compose YAML itself before assuming the network section is omitted.
  8. Open Advanced for Depends on, Env files, Labels, User, Working directory, Command override, or Profiles only when the service needs those entries.
  9. Read Deployment Checks, then copy or download Compose YAML. Use Env Example only when secret-like values were converted to required environment references.

Finish by comparing Service Blueprint with the YAML text. The table is easier to scan; the YAML is what Compose will read.

Interpreting Results:

Compose YAML is the copy-ready draft, but the review tables explain whether it should be trusted. The most important checks are image pinning, port exposure, secret handling, healthcheck status, restart policy, fixed container name, and writable bind mounts. A clean-looking YAML block can still carry a risky default if those rows were skipped.

  • Service Blueprint summarizes what was emitted: service key, runtime source, ports, environment count, volume count, dependency conditions, healthcheck command, restart policy, and network entry.
  • Deployment Checks uses Pass, Review, Warning, and Info to separate acceptable choices from settings that deserve another look.
  • Env Example appears when secret-like keys were converted to required environment references. It is a starter file, not a safe place for real credentials by default.
  • JSON mirrors the parameters, generated text, parsed rows, and checks for handoff or issue comments.

Do not read Pass as production approval. It means the static checks found a reasonable first draft for that row. The final check is a host-side Compose run, followed by logs, health state, and a port/mount review in the actual project environment.

Worked Examples:

Local API from a pinned image

An API service named api uses image mode with ghcr.io/example/orders-api:2026.05, port 127.0.0.1:8080:3000, environment rows APP_ENV=production and API_TOKEN=change-me, and volume ./app:/usr/src/app:ro. Compose YAML emits an image service with a private host bind, read-only source mount, restart policy, and HTTP healthcheck. Env Example includes API_TOKEN=change-me because the secret policy converted the token row to a required environment reference.

Deployment Checks should show image pinning as Pass, port binding as Pass, secret handling as Pass, and healthcheck as Pass when the default HTTP probe is present. That does not prove the image serves /health; it means the draft has the expected readiness declaration and the host-side run should verify it.

Build-mode worker with no published port

A worker service named worker uses Local build context with context ., no Ports, environment QUEUE=default, and restart policy on-failure. Compose YAML writes a build block instead of an image entry. Service Blueprint reports no published ports, which fits a queue worker that only talks to services on the Compose network.

Deployment Checks labels the port row as Info, not failure. The main follow-up is the healthcheck choice. If the worker has no HTTP endpoint, use Shell command with a command that actually proves the worker can reach its queue or process loop.

Secret value kept literal by mistake

A service has DATABASE_URL=postgres://app:change-me@db:5432/app, but Secret handling is set to Keep literal values in Compose. Compose YAML keeps the connection string in the environment map and Env Example stays empty. Deployment Checks marks secret handling as Warning because a secret-looking value remains in the YAML.

The corrective path is to switch back to Reference secret-like keys from .env, then confirm Compose YAML contains a required environment reference and Env Example lists the key that needs to be supplied outside the main Compose text.

FAQ:

Does the generated YAML include more than one service?

No. The output drafts one service and optional top-level network or volume entries. Use it as a service block starting point when building a larger Compose file.

Why did the image check warn about my image name?

The check warns when image mode uses :latest or no tag or digest. Add a version tag or digest when the same Compose file should pull a repeatable runtime.

What port format can I enter?

Use one mapping per line, such as 8080:3000, 127.0.0.1:8080:3000, 3000, or 3000/udp. A published host port without a host IP gets a review note.

Why is my environment key rejected?

Environment keys must look like shell variable names: start with a letter or underscore, then use letters, numbers, or underscores. Fix the key before using the generated YAML.

Does a healthcheck make dependencies wait for readiness?

A healthcheck gives a service a health state. A dependent service waits for that state only when Depends on emits a condition such as service_healthy for the dependency.

Is the Compose content sent to a server for generation?

No server-side generator is used for this tool. The page builds the YAML and review tables in the browser, but copied text, downloaded files, and screenshots still need normal secret-handling care.

Glossary:

Compose service
A named container workload under the top-level services map.
Runtime source
The image pull or local build context used to create the service container.
Host bind
A port mapping or volume mount that connects the container to a host address or host path.
Named volume
A persistent Docker-managed storage object declared at the top level and mounted into a service.
Healthcheck
A command Docker runs inside the container to report whether the service is healthy.
Dependency condition
A depends_on rule such as service_started, service_healthy, or service_completed_successfully.

References: