Prowler is a monorepo composed of several runtime components — Prowler App (the web user interface), Prowler API (the backend), Prowler SDK, and Prowler MCP Server (Model Context Protocol) — that frequently share a single .env file. To keep that shared configuration unambiguous, each component namespaces its environment variables with a component-specific prefix.
Component Prefixes
Each component owns a dedicated prefix for the environment variables it reads:
| Component | Prefix | Status |
|---|
| Prowler App (web UI) | UI_ | Adopted |
| Prowler API (backend) | API_ | Planned |
| Prowler SDK | SDK_ | Planned |
| Prowler MCP Server | MCP_ | Planned |
Why Component Prefixes Matter
Component prefixes solve three concrete problems in a shared configuration file:
- Collisions in a shared
.env: Several components historically read identically named variables. The API base URL, for example, is consumed by more than one component, so a single unprefixed name is ambiguous. A component prefix removes that ambiguity.
- Explicit ownership: A prefix states, at a glance, which component consumes a variable.
- Reduced accidental exposure: For Prowler App, scoping browser-facing configuration under one intentional prefix prevents server-only values from leaking into the client bundle.
Prowler App
Prowler App has adopted the UI_ prefix. Its public configuration is resolved from the container environment at runtime rather than inlined at build time, so a single pre-built image serves any deployment. For the operational details on changing these values without rebuilding the image, see Troubleshooting.
The former build-time variables map to the new runtime variables as follows:
| Former variable | New variable |
|---|
NEXT_PUBLIC_API_BASE_URL | UI_API_BASE_URL |
NEXT_PUBLIC_API_DOCS_URL | UI_API_DOCS_URL |
NEXT_PUBLIC_GOOGLE_TAG_MANAGER_ID | UI_GOOGLE_TAG_MANAGER_ID |
NEXT_PUBLIC_SENTRY_DSN, SENTRY_DSN | UI_SENTRY_DSN |
NEXT_PUBLIC_SENTRY_ENVIRONMENT, SENTRY_ENVIRONMENT | UI_SENTRY_ENVIRONMENT |
SENTRY_ORG, SENTRY_PROJECT, SENTRY_AUTH_TOKEN, and SENTRY_RELEASE — keep their names, as they are not part of the App’s runtime configuration.
Enabling Third-Party Integrations
Prowler App gates each optional third-party integration behind an explicit enable flag. When an integration is configured through its new UI_* variables, it loads only when its flag is set to the exact string "true"; any other value, including unset, leaves it off. This default-off behavior keeps a deployment free of third-party egress unless it opts in. Deployments still using the deprecated legacy variable names keep loading without the flag, for backward compatibility (see Deprecated Names).
| Integration | Enable flag | Required configuration when enabled |
|---|
| Sentry (error monitoring) | UI_SENTRY_ENABLE | UI_SENTRY_DSN |
| Google Tag Manager | UI_GOOGLE_TAG_MANAGER_ENABLE | UI_GOOGLE_TAG_MANAGER_ID |
| PostHog (product analytics) | UI_POSTHOG_ENABLE | UI_POSTHOG_KEY and UI_POSTHOG_HOST |
UI_* value set while its enable flag is not "true" is ignored, and the server logs a one-time startup warning noting that the integration will not load. Legacy names follow the backward-compatible rule described in Deprecated Names.
PostHog support is currently limited to configuration validation: Prowler App reads and validates the PostHog variables but does not yet load a PostHog client.
Configuring an integration through the new UI_* variables now requires its enable flag. A deployment that adopted UI_SENTRY_DSN or UI_GOOGLE_TAG_MANAGER_ID must also set UI_SENTRY_ENABLE=true or UI_GOOGLE_TAG_MANAGER_ENABLE=true to keep the integration active. Deployments still using the legacy names (NEXT_PUBLIC_*, or POSTHOG_KEY and POSTHOG_HOST) keep working without the flag.
Upcoming Breaking Change
Adopting the API_, SDK_, and MCP_ prefixes for Prowler API, Prowler SDK, and Prowler MCP Server is a planned breaking change in a future release. Migrate environment configuration to the new names when upgrading.
API_, SDK_, and MCP_ respectively. The per-component mapping from current to prefixed names will be documented when each change is released.
Deprecated Names
- Prowler App: The bare server-side
SENTRY_DSN and SENTRY_ENVIRONMENT are no longer read; the server and edge runtimes now read UI_SENTRY_DSN and UI_SENTRY_ENVIRONMENT. The former NEXT_PUBLIC_* names — and, for PostHog, the unprefixed POSTHOG_KEY and POSTHOG_HOST — are deprecated but stay backward compatible: they are read at runtime regardless of the enable flag, so an existing deployment keeps its integration active without opting in. The new UI_* names, by contrast, load only when the matching enable flag is set to "true". These legacy names will be removed in a future release, so migrate to the UI_* runtime variables — and set the enable flag — on the running container.
- Prowler API, Prowler SDK, and Prowler MCP Server: The current, unprefixed variable names are deprecated. They continue to work today and will be removed once the prefixed convention is adopted for each component, as described in Upcoming Breaking Change.
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