Maybe Finance on Google Cloud Run

Maybe (Maybe Finance) is an open-source, self-hosted alternative to Mint/Monarch for personal finance and wealth management — budgeting, net-worth tracking, transaction categorization, and multi-account aggregation, built on Ruby on Rails. This module deploys Maybe on Cloud Run v2 on top of the App_CloudRun foundation, which provisions and manages the shared Google Cloud infrastructure.

This guide focuses on the cloud services Maybe uses and how to explore and operate them from the Google Cloud Console and the command line. For the mechanics common to every Cloud Run application — service identity, ingress and load balancing, scaling and concurrency, CI/CD, Cloud Armor, IAP, Binary Authorization, VPC Service Controls, backups, and the deployment lifecycle — refer to the App_CloudRun foundation guide rather than repeating them here.

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1. Overview

Maybe runs as a single Rails/Puma container on Cloud Run v2, with a Sidekiq background-job process started alongside it inside the same container by the cloud entrypoint. The deployment wires together a focused set of Google Cloud services:

Capability	Google Cloud service	Notes
Compute	Cloud Run v2	Rails/Puma on port 3000, 2 vCPU / 4 GiB by default; Sidekiq runs as a background process inside the same container
Database	Cloud SQL for PostgreSQL 15	Required — a plan-time guard accepts only POSTGRES_13/14/15 (or NONE); MySQL is rejected
Background jobs & real-time UI	Redis (via the shared NFS VM, or an explicit host)	Mandatory — a plan-time precondition fails the plan if enable_redis = false; powers Sidekiq (account syncing, import processing, notifications)
File persistence	Cloud Filestore (NFS)	Attachments persist under /opt/maybefinance/storage; also the default source for the Redis host IP
Object storage	Cloud Storage	A storage bucket is auto-provisioned by MaybeFinance_Common; the default storage_buckets variable adds a data bucket
Secrets	Secret Manager	Auto-generated SECRET_KEY_BASE (Rails session/encryption key); database password
Ingress	Cloud Run URL / Cloud Load Balancing	Default run.app URL; optional external HTTPS load balancer + custom domain

Sensible defaults worth knowing up front:

• PostgreSQL 15 is mandatory. database_type defaults to POSTGRES_15 and a plan-time precondition (validation.tf) rejects anything other than POSTGRES_13/14/15/NONE — MySQL is not supported.
• Redis is mandatory, not optional. A plan-time precondition fails the plan outright if enable_redis = false. When redis_host is left blank, enable_nfs must stay true so the shared NFS server's IP is used as the Redis host.
• Cloud SQL is reached over private-IP TCP, not a socket, by default. Unlike most Common-module apps, enable_cloudsql_volume defaults to false here: Rails' pg driver cannot parse the Cloud SQL Unix-socket DSN, so the module skips the Auth Proxy sidecar and connects over the instance's private IP instead. The cloud entrypoint maps the Foundation's DB_HOST/DB_PORT/DB_NAME/DB_USER/DB_PASSWORD onto Maybe's discrete DB_HOST/DB_PORT/POSTGRES_DB/POSTGRES_USER/POSTGRES_PASSWORD env vars and sets PGSSLMODE=require (Cloud SQL rejects unencrypted private-IP TCP); if enable_cloudsql_volume is switched on, DB_HOST becomes a socket directory and the entrypoint falls back to DB_IP over TCP instead of trying to use the socket path directly.
• Scale-to-zero is the default (min_instance_count = 0, cpu_always_allocated = false). This is a cost-first default, but it means the co-located Sidekiq worker only runs while an instance happens to be alive — set min_instance_count = 1 and cpu_always_allocated = true to keep background jobs (account syncing, import processing, notifications) running continuously, matching the GKE variant's defaults.
• Combined web + worker container, not a sidecar. The cloud entrypoint starts bundle exec sidekiq in the background and then execs the Rails web server in the foreground of the same container — Maybe is not deployed with a separate additional_services worker. If REDIS_URL resolves empty, the entrypoint skips starting Sidekiq entirely rather than crashing.
• SECRET_KEY_BASE is generated once by MaybeFinance_Common and stored in Secret Manager, shared identically by the web and Sidekiq processes. Rails uses it to sign sessions/cookies and to derive the key that encrypts ActiveRecord-encrypted columns.
• Schema is created by an init job, not on boot. The maybefinance-migrate job runs rails db:prepare during apply; the runtime entrypoint never runs migrations.
• container_image_source = "custom". Cloud Build builds a thin wrapper image FROM ghcr.io/maybe-finance/maybe:<version>. application_version defaults to "stable"; a "latest" request is mapped to the pinned stable channel via the app-specific MAYBE_VERSION build ARG (the Foundation's generic APP_VERSION build arg is intentionally not used).

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2. Google Cloud Services & How to Explore Them

All commands assume PROJECT and REGION are set. Service and resource names are reported in the deployment Outputs.

A. Cloud Run — the Maybe service (web + Sidekiq)

Maybe runs as a Cloud Run v2 service that autoscales by request load between the minimum and maximum instance counts. The Rails/Puma web server and the Sidekiq worker run as two processes inside the same container, sharing SECRET_KEY_BASE and the Redis connection. Each deployment creates an immutable revision; traffic can be split across revisions for safe rollouts.

• Console: Cloud Run → select the service for revisions, traffic, logs, and metrics.
• CLI:

  gcloud run services list --project "$PROJECT" --region "$REGION"
  gcloud run services describe <service-name> --project "$PROJECT" --region "$REGION"
  gcloud run revisions list --service <service-name> --project "$PROJECT" --region "$REGION"

See App_CloudRun for scaling, concurrency, execution environment, and traffic splitting.

B. Cloud SQL for PostgreSQL 15

Maybe stores all application data (accounts, transactions, budgets, users) in a managed Cloud SQL for PostgreSQL 15 instance. Unlike the GKE variant (which reaches Cloud SQL through a loopback Auth Proxy sidecar), the Cloud Run service connects over the instance's private IP with sslmode=require — enable_cloudsql_volume defaults false because Rails cannot parse the socket-style DSN the proxy would otherwise present. On first deploy the db-init job creates the application database and user, grants the app role cloudsqlsuperuser (so Maybe's own migration can create Postgres extensions without superuser access), and pre-creates the pgcrypto extension; maybefinance-migrate then runs rails db:prepare.

• Console: SQL → select the instance for connections, backups, flags, metrics.
• CLI:

  gcloud sql instances list --project "$PROJECT"
  gcloud sql instances describe <instance-name> --project "$PROJECT"
  gcloud sql connect <instance-name> --user=<db-user> --database=<db-name> --project "$PROJECT"

The instance name, database, user, and password secret are in the Outputs. See App_CloudRun for the connection model, backups, and password rotation.

C. Cloud Filestore (NFS) & Redis

Cloud Filestore (NFS) is mounted at /opt/maybefinance/storage (enable_nfs = true by default) so uploaded attachments persist across revisions. Maybe also requires Redis, which is mandatory — a plan-time precondition blocks enable_redis = false. When redis_host is left blank, the injected REDIS_HOST resolves to the shared NFS server's IP (the NFS VM co-hosts Redis in this repo's platform convention), which is why enable_nfs must stay true unless an explicit redis_host is supplied.

• Console: Filestore → Instances; Compute Engine → VM instances (the NFS VM, if it also runs Redis).
• CLI:

  gcloud filestore instances list --project "$PROJECT"
  redis-cli -h <redis-host> ping
  gcloud run services describe <service-name> --region "$REGION" \
    --format='value(spec.template.spec.containers[0].env)'

See App_CloudRun for NFS discovery/provisioning and Redis injection mechanics.

D. Cloud Storage

A storage bucket is provisioned automatically by MaybeFinance_Common, and the default storage_buckets variable adds a second data bucket. Neither is mounted into the container filesystem by default — gcs_volumes is empty out of the box — so they exist as provisioned storage but are inert until explicitly wired up.

• Console: Cloud Storage → Buckets.
• CLI:

  gcloud storage buckets list --project "$PROJECT" --filter="name~maybefinance"

See App_CloudRun for GCS Fuse and CMEK options.

E. Secret Manager

One Maybe-specific secret is generated automatically and stored in Secret Manager: SECRET_KEY_BASE (secret-<prefix>-maybefinance-secret-key-base), a 64-character random value shared by the Rails web process and the Sidekiq worker. The database password is managed separately by the foundation.

• Console: Security → Secret Manager.
• CLI:

  gcloud secrets list --project "$PROJECT" --filter="name~maybefinance"
  gcloud secrets versions access latest --secret=<secret-key-base-name> --project "$PROJECT"

See App_CloudRun for injection and rotation details.

F. Networking & ingress

The service is reachable at its run.app URL by default (ingress_settings = "all"). An external HTTPS load balancer with a custom domain, Cloud CDN, and Cloud Armor can be layered on; ingress settings and VPC egress control connectivity.

• Console: Cloud Run (service URL); Network services → Load balancing.
• CLI:

  gcloud run services describe <service-name> --region "$REGION" --format='value(status.url)'
  gcloud compute addresses list --project "$PROJECT"

See App_CloudRun.

G. Cloud Logging & Monitoring

Container logs (RAILS_LOG_TO_STDOUT = "true") flow to Cloud Logging; Cloud Run and Cloud SQL metrics flow to Cloud Monitoring, with optional uptime checks and alert policies.

• Console: Logging → Logs Explorer; Monitoring → Dashboards / Alerting.
• CLI:

  gcloud run services logs read <service-name> --project "$PROJECT" --region "$REGION" --limit 50

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3. Maybe Finance Application Behaviour

• First-deploy database setup. The db-init job runs db-init.sh using postgres:15-alpine. It connects over private-IP TCP (sslmode=require), idempotently creates the application database and user, grants privileges, grants the app role cloudsqlsuperuser (Cloud SQL's app users aren't real superusers, so this lets Maybe's own migration create Postgres extensions), and pre-creates pgcrypto as a belt-and-suspenders step. The job is safe to re-run.
• Schema migration is a separate init job. maybefinance-migrate runs bundle exec rails db:prepare against the built Maybe image (image = null in its job spec, so it reuses the image and toolchain built for the app), depends on db-init completing first, and retries up to 3 times (max_retries = 3, timeout_seconds = 1200, memory_limit = 2Gi).
• First-run admin registration, not an auto-created secret. SELF_HOSTED = "true" enables Maybe's self-host UI, which lets the first visitor register the initial admin account through the web UI — there is no auto-generated admin password secret to retrieve.
• SECRET_KEY_BASE is immutable in practice. It is generated once by MaybeFinance_Common and shared by the web and Sidekiq processes. Rotating it after first boot invalidates existing sessions and makes ActiveRecord-encrypted columns unreadable.
• DB env-var mapping happens in the cloud entrypoint, not a URL DSN. The platform injects DB_HOST (the instance private IP on Cloud Run, since enable_cloudsql_volume defaults false), DB_PORT, DB_NAME, DB_USER, DB_PASSWORD, and DB_IP; the entrypoint maps these onto POSTGRES_DB/POSTGRES_USER/POSTGRES_PASSWORD (Maybe's Rails config/database.yml convention) and sets PGSSLMODE=require because the resolved host is a real private IP, not loopback.
• Redis wiring. REDIS_URL is built from the injected REDIS_HOST/ REDIS_PORT/REDIS_AUTH if not already set. If REDIS_URL ends up empty (Redis unreachable), the entrypoint skips starting Sidekiq entirely — background jobs silently stop running rather than crashing the container.
• Background jobs need an always-warm instance. Because Sidekiq is started in-process by the entrypoint, it only runs while a container instance is alive. With the CloudRun defaults (min_instance_count = 0, cpu_always_allocated = false), scale-to-zero periods and CPU throttling between requests both interrupt background job processing.
• Health path. Startup probe is HTTP GET /up with a generous allowance for a slow first boot (initial_delay_seconds = 60, period_seconds = 15, failure_threshold = 30 — roughly 8 minutes of headroom). Liveness probe is also HTTP GET /up (initial_delay_seconds = 60, period_seconds = 30, failure_threshold = 3).
• Inspect job execution:

  gcloud run jobs list --project "$PROJECT" --region "$REGION"
  gcloud run jobs executions list --job <db-init-job-name> --project "$PROJECT" --region "$REGION"
  gcloud run jobs executions list --job <maybefinance-migrate-job-name> --project "$PROJECT" --region "$REGION"

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4. Configuration Variables

Variables are grouped exactly as they appear on the deployment platform (the {{UIMeta group=N}} tag in each variable's description in variables.tf). Only settings specific to or notable for Maybe are listed; every other input is inherited from App_CloudRun with its standard behaviour and defaults.

Group 1 — Project & Identity

Variable	Default	Description
project_id	(required)	Target Google Cloud project.
region	us-central1	Region for the service and regional resources.

Group 2 — Deployment Environment

Variable	Default	Description
tenant_deployment_id	demo	Short suffix that makes resource names unique per environment.
support_users	[]	Emails granted project access and monitoring alerts.
resource_labels	{}	Labels applied to all resources.

Group 3 — Application Identity

Variable	Default	Description
application_name	maybefinance	Base name for resources. Do not change after first deploy.
display_name	Maybe	Human-readable name shown in the Console.
description	(set)	Service description.
application_version	stable	ghcr.io/maybe-finance/maybe image tag used as the custom-build base; latest is mapped to the pinned stable release channel via MAYBE_VERSION.

application_display_name/application_description are inert Foundation mirror declarations (never forwarded to the Foundation call) — the effective identity comes from display_name/description above.

Group 4 — Runtime & Scaling

Variable	Default	Description
deploy_application	true	Set false to provision infrastructure only.
container_image_source	custom	Thin wrapper image built FROM the upstream GHCR image.
cpu_limit	2000m	CPU per instance.
memory_limit	4Gi	Memory per instance; Maybe recommends at least 2Gi.
cpu_always_allocated	false	Cost-first cold-start default. Set true (with min_instance_count >= 1) to keep Sidekiq processing continuously.
container_resources	(null)	Overrides cpu_limit/memory_limit when set.
min_instance_count	0	Scale-to-zero by default — differs from the GKE variant's min=1; stops the co-located Sidekiq worker between requests.
max_instance_count	5	Cost ceiling.
container_port	3000	Maybe's native Rails/Puma port.
execution_environment	gen2	Gen2 required for NFS and GCS Fuse mounts.
timeout_seconds	300	Maximum request duration (0–3600 seconds).
enable_cloudsql_volume	false	Off by default for Maybe — Rails can't parse the Cloud SQL socket DSN, so the app connects over private-IP TCP instead.
cloudsql_volume_mount_path	/cloudsql	Only relevant if enable_cloudsql_volume is switched on.
container_protocol	http1	HTTP protocol version.
traffic_split	[]	Split traffic across revisions for staged rollouts.
max_revisions_to_retain	7	Declared for convention parity; not referenced by this module's deployment.
enable_image_mirroring	true	Always true — the GHCR base image is mirrored into Artifact Registry before the wrapper build.
container_build_config	{ enabled = true }	Build settings; MAYBE_VERSION build ARG is set from application_version in MaybeFinance_Common, not exposed as a top-level variable.
additional_services / additional_containers	[]	Not used by Maybe (Sidekiq runs in-process, not as a sidecar or separate service).

Group 5 — Access & Networking

Variable	Default	Description
ingress_settings	all	Public reachability for the web UI.
vpc_egress_setting	PRIVATE_RANGES_ONLY	Route only RFC 1918 traffic via VPC.
enable_iap	false	Require Google sign-in.
iap_authorized_users / iap_authorized_groups	[]	Who may access through IAP.
network_name	""	Auto-discovers the Services_GCP-managed VPC network.

Group 6 — Environment Variables & Secrets

Variable	Default	Description
environment_variables	{}	Extra non-secret settings. Core Rails/Maybe values (RAILS_ENV, SELF_HOSTED, RAILS_LOG_TO_STDOUT, etc.) are set automatically by MaybeFinance_Common.
secret_environment_variables	{}	Map of env var → Secret Manager secret name.
secret_propagation_delay	30	Seconds to wait after secret creation before proceeding.
secret_rotation_period	2592000s	Secret Manager rotation notification frequency.

Group 7 — Backup & Restore

Variable	Default	Description
backup_schedule	0 2 * * *	Automated backup cron (UTC).
backup_retention_days	7	Retention; raise for production/compliance.
enable_backup_import / backup_source / backup_file / backup_format	restore options	Restore from a backup on deploy.

Group 8 — CI/CD & Binary Authorization

Standard App_CloudRun Cloud Build / Cloud Deploy integration — see App_CloudRun. Key inputs: enable_cicd_trigger, github_repository_url, github_token, enable_cloud_deploy, enable_binary_authorization.

Group 9 — Custom Initialization & SQL

enable_custom_sql_scripts, custom_sql_scripts_bucket, custom_sql_scripts_path, custom_sql_scripts_use_root — run SQL from a GCS bucket after provisioning. See App_CloudRun.

Group 10 — Load Balancer, CDN & Image Retention

Variable	Default	Description
enable_cloud_armor	false	Provision Global HTTPS LB + Cloud Armor WAF.
admin_ip_ranges	[]	CIDR ranges exempted from WAF rules.
application_domains	[]	Custom domain names for the HTTPS LB.
enable_cdn	false	Enable Cloud CDN on the HTTPS LB backend.
max_images_to_retain / delete_untagged_images / image_retention_days	(set)	Artifact Registry cleanup policy.

Group 11 — Storage & Filesystem

Variable	Default	Description
create_cloud_storage	true	Create GCS buckets defined in storage_buckets.
storage_buckets	[{ name_suffix = "data" }]	Additional GCS bucket beyond the auto-provisioned storage bucket.
enable_nfs	true	Attachments persist and are shared across revisions; also the default source for the Redis host IP.
nfs_mount_path	/opt/maybefinance/storage	Where Maybe stores uploaded attachments.
nfs_instance_name / nfs_instance_base_name	(auto-discover)	Existing/inline NFS VM naming.
gcs_volumes	[]	GCS Fuse volume mounts (requires gen2); not used out of the box.
manage_storage_kms_iam / enable_artifact_registry_cmek	false	CMEK options.

Group 12 — Database Backend

Variable	Default	Description
database_type	POSTGRES_15	A plan-time precondition restricts this to POSTGRES_13/14/15/NONE; MySQL is rejected.
db_name	maybefinance	Effective PostgreSQL database name. Immutable after first deploy.
db_user	maybefinance	Effective application database user; password auto-generated in Secret Manager.
database_password_length	32	Generated password length (16–64).
enable_auto_password_rotation / rotation_propagation_delay_sec	off	DB password rotation.
enable_postgres_extensions / postgres_extensions	false / []	Left off — db-init.sh already pre-creates pgcrypto via the cloudsqlsuperuser grant.
enable_mysql_plugins / mysql_plugins	false / []	Unused — Maybe is PostgreSQL-only.
application_database_name / application_database_user	crappdb / crappuser	Inert Foundation-mirror declarations (never forwarded to main.tf) — the real database name/user come from db_name/db_user above via MaybeFinance_Common.

Group 13 — Jobs & Scheduled Tasks

Variable	Default	Description
initialization_jobs	[]	Leave empty to use the built-in db-init + maybefinance-migrate jobs.
cron_jobs	[]	Not forwarded — Maybe has no platform-scheduled recurring tasks; its own background work runs in-process via Sidekiq.

Group 14 — Observability & Health

Variable	Default	Description
startup_probe	HTTP /up, 60s delay, 30 retries	Startup probe. Allow roughly 8 minutes on first boot.
liveness_probe	HTTP /up, 60s delay	Liveness probe.
startup_probe_config / health_check_config	HTTP /up	Alternative structured probes.
uptime_check_config	{ enabled=false, path="/" }	Cloud Monitoring uptime check; disabled by default, enable explicitly to activate.
alert_policies	[]	Metric alert policies.

Group 21 — Redis Cache & Queue

Variable	Default	Description
enable_redis	true	Mandatory — a plan-time precondition fails the plan if set to false.
redis_host	""	Leave blank to use the NFS server IP (requires enable_nfs = true).
redis_port	6379	Redis port.
redis_auth	""	Optional Redis auth password (sensitive).

Group 22 — VPC Service Controls & Audit Logging

Variable	Default	Description
enable_vpc_sc	false	Enforce a VPC-SC perimeter (requires organization_id).
vpc_cidr_ranges / vpc_sc_dry_run	(set)	Access level CIDRs / dry-run mode.
enable_audit_logging	false	Detailed Cloud Audit Logs.

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5. Outputs

Returned on a successful deployment — the quickest way to locate and explore the running resources.

Output	Description
service_name	Cloud Run service name.
service_url	Default run.app URL of the service.
service_location	Region the service runs in.
stage_services	Stage-specific service URLs (Cloud Deploy).
load_balancer_ip / load_balancer_url	External HTTPS load balancer IP / URL (when enabled).
database_instance_name	Cloud SQL instance name.
database_name / database_user	Application database name / user.
database_password_secret	Secret Manager secret holding the DB password.
database_host / database_port	DB endpoint (private IP on Cloud Run) / port.
storage_buckets	Created Cloud Storage buckets.
network_name / network_exists / regions	VPC network, presence, regions.
container_image / container_registry	Deployed image and Artifact Registry repo.
monitoring_enabled / monitoring_notification_channels / uptime_check_names	Monitoring status, channels, uptime checks.
initialization_jobs	Names of the setup jobs (db-init, maybefinance-migrate).
deployment_id / tenant_id / resource_prefix	Naming identifiers.
project_id / project_number	Project identifiers.
cicd_enabled / github_repository_url / github_repository_owner / github_repository_name / cicd_configuration	CI/CD status and details.
artifact_registry_repository / cloudbuild_trigger_name / cloudbuild_trigger_id	Registry and build trigger.
vpc_sc_enabled / vpc_sc_perimeter_name / vpc_sc_dry_run_mode	VPC-SC status.
audit_logging_enabled / artifact_registry_cmek_enabled	Audit logging and CMEK status.

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6. Configuration Pitfalls & Sensible Defaults

Risk: Critical (data loss / outage / security) — High (service degraded) — Medium (cost or partial degradation) — Low (minor).

Inherited plan-time validation. This module passes its configuration through the App_CloudRun foundation engine, plus its own validation.tf guards (min ≤ max, Redis mandatory, a Redis host must be resolvable, PostgreSQL-only database_type, no Auth Proxy without a real database). Invalid configuration fails the plan with a clear, named error before any resource is created, so most mistakes below are caught up front rather than at apply or runtime.

Setting	Sensible value	Risk	Consequence if wrong
database_type	POSTGRES_15 (or 13/14)	Critical	A non-PostgreSQL engine is rejected at plan time; forcing one around the guard breaks the installer and every query.
enable_redis	true	Critical	The plan-time precondition blocks false outright — Maybe has no functioning background-job queue without Redis.
db_name / db_user	Set once	Critical	Immutable after first deploy; renaming recreates the DB/user and destroys all data.
SECRET_KEY_BASE (auto-generated)	Never rotate after first boot	Critical	Rotating it invalidates all sessions and makes ActiveRecord-encrypted columns unreadable.
enable_cloudsql_volume	false (Cloud Run)	Critical	Switching it on changes DB_HOST to a socket directory Rails cannot parse directly; the entrypoint falls back to DB_IP, but a mis-set database_type = "NONE" combined with enable_cloudsql_volume = true is blocked at plan time because the proxy sidecar would have no instance to connect to.
redis_host	"" (NFS) or explicit	High	When Redis is on but enable_nfs is off and no host is set, the plan-time precondition fails; if enable_nfs is disabled after a working deploy, uploaded attachments become ephemeral and the Redis host may go stale.
min_instance_count / cpu_always_allocated	1 / true for production	High	With the cost-first defaults (0 / false), the co-located Sidekiq worker only runs while an instance happens to be alive — account syncing, import processing, and notifications silently stop firing between requests and during scale-to-zero windows.
memory_limit	4Gi (default)	High	The combined Rails + Sidekiq process is memory-hungry under import/sync workloads; Maybe recommends at least 2Gi.
SELF_HOSTED (auto-injected "true")	Register the first admin promptly	High	Leaving the deployment reachable before an admin registers allows anyone with the URL to claim the initial administrator account.
ingress_settings	all	Medium	Setting to internal blocks access to the web UI for anyone outside the VPC.
backup_retention_days	7 (raise for prod)	Medium	Too short for compliance retention.
enable_cloud_armor	enable for production	Medium	The admin UI is publicly reachable without WAF protection.

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For the foundation behaviour referenced throughout — service identity, scaling and concurrency, ingress and load balancing, CI/CD, Cloud Armor, IAP, Binary Authorization, VPC-SC, backups, and image mirroring — see App_CloudRun. Maybe-specific application configuration shared with the GKE variant lives in the MaybeFinance_Common module (its own docs/modules/MaybeFinance_Common.md guide has not been published yet).