feature-switch

name	feature-switch
description	Feature switch system guide for gating new user-facing features behind feature flags

Feature Switch Skill

This skill documents the feature switch system and provides step-by-step instructions for adding new feature switches. All new user-facing features must be gated behind a feature switch for gradual rollout.

When to Use

A feature switch is required when adding:

• New UI pages, sections, or sidebar navigation items
• New API endpoints exposed to users or agents
• New integrations (connectors, Slack, Telegram, etc.)
• New zero token capabilities

A feature switch is not required for:

• Internal refactors or code cleanup
• Test infrastructure changes
• Build/CI configuration
• Bug fixes to existing features
• Documentation updates

How to Add a Feature Switch

Step 1: Add a key to the enum

File: turbo/packages/core/src/feature-switch-key.ts

Add a new entry to FeatureSwitchKey:

export enum FeatureSwitchKey {
  // ... existing keys
  MyFeature = "myFeature",
}

Step 2: Register the switch

File: turbo/packages/core/src/feature-switch.ts

Add an entry to the FEATURE_SWITCHES record:

[FeatureSwitchKey.MyFeature]: {
  maintainer: "[e-mail]",
  enabled: false,
  enabledOrgIdHashes: STAFF_ORG_ID_HASHES, // optional: staff-only access
},

Configuration options:

Field	Type	Description
maintainer	string	Email of the responsible person
enabled	boolean	true = on for everyone, false = off by default
enabledUserHashes	string[]	FNV-1a hashes of allowed user IDs
enabledEmailHashes	string[]	FNV-1a hashes of allowed emails
enabledOrgIdHashes	string[]	FNV-1a hashes of allowed org IDs

Common default states:

• enabled: false — fully hidden until manually enabled via Lab page
• enabled: false + enabledOrgIdHashes: STAFF_ORG_ID_HASHES — staff-only (most common for new features)
• enabled: true — on for everyone (use when feature is ready for GA)

Step 3: Gate the feature in application code

Choose the pattern that matches where your feature is consumed.

Server-side (API routes)

import { isFeatureEnabled, FeatureSwitchKey } from "@vm0/core";

// In route handler:
if (!isFeatureEnabled(FeatureSwitchKey.MyFeature, { userId, orgId })) {
  return createErrorResponse("FORBIDDEN", "Feature not available");
}

Client-side (Platform UI)

import { FeatureSwitchKey } from "@vm0/core";
import { featureSwitch$ } from "../../signals/external/feature-switch.ts";

// In component:
const features = useLastResolved(featureSwitch$);
const showMyFeature = features?.[FeatureSwitchKey.MyFeature] ?? false;

// Conditional rendering:
{showMyFeature && <MyFeatureComponent />}

Sidebar navigation gating

In turbo/apps/platform/src/views/zero-page/zero-sidebar.tsx, add a featureGate to the sidebar item:

{
  id: "my-feature",
  label: "My Feature",
  icon: MyIcon,
  featureGate: FeatureSwitchKey.MyFeature,
}

Connector gating

In turbo/packages/core/src/contracts/connectors.ts, add featureFlag to the connector config:

myConnector: {
  label: "My Connector",
  featureFlag: FeatureSwitchKey.MyConnector,
  // ...
}

Zero token capability gating

In turbo/apps/web/src/lib/auth/sandbox-token.ts, add to CONDITIONAL_CAPABILITIES:

const CONDITIONAL_CAPABILITIES: ReadonlyMap<ZeroCapability, FeatureSwitchKey> =
  new Map([
    // ... existing entries
    ["my-feature:write", FeatureSwitchKey.MyFeature],
  ]);

Key Files

File	Role
turbo/packages/core/src/feature-switch-key.ts	Enum of all feature switch keys
turbo/packages/core/src/feature-switch.ts	Registry and evaluation logic
turbo/apps/platform/src/signals/external/feature-switch.ts	Client-side reactive state with override layers
turbo/apps/platform/src/views/zero-page/zero-sidebar.tsx	Sidebar nav items with featureGate
turbo/packages/core/src/contracts/connectors.ts	Connector type definitions with featureFlag field
turbo/apps/web/src/lib/auth/sandbox-token.ts	Token capability gating

Override Layers

Evaluation has two layers (lowest to highest priority):

1. Core registry — static config in source code, evaluated against userId / email / orgId hashes.
2. Per-user DB overrides — row in user_feature_switches keyed by (orgId, userId). Written via the Lab page toggles or window._vm0.featureSwitches.myFeature = true (both call POST /api/zero/feature-switches). Cleared via the Lab page "Reset all" button (DELETE /api/zero/feature-switches).

The same two-layer resolution applies on the server: route handlers that call isFeatureEnabled(..., { userId, orgId, overrides }) pass overrides loaded via loadFeatureSwitchOverrides(orgId, userId).

There is no client-only layer. window._vm0.featureSwitches requires auth and persists across refreshes; there is no device-local override.