Configuration

FxEmbed is configured through environment variables (.env), Wrangler settings (wrangler.toml), and an optional branding file (branding.json).

Environment Variables

Copy .env.example to .env and configure:

Domain Lists

These comma-separated lists define which domains route to which realm:

Variable	Description	Example
`STANDARD_DOMAIN_LIST`	X/Twitter embed domains	`fxtwitter.com,fixupx.com,twittpr.com`
`STANDARD_BSKY_DOMAIN_LIST`	Bluesky embed domains	`fxbsky.app`
`STANDARD_TIKTOK_DOMAIN_LIST`	TikTok embed domains	`fixtok.example.com`

Subdomain Feature Domains

Variable	Description	Example
`DIRECT_MEDIA_DOMAINS`	`d.`/`dl.` direct media subdomains	`d.fxtwitter.com,dl.fxtwitter.com`
`TEXT_ONLY_DOMAINS`	`t.` text-only subdomains	`t.fxtwitter.com`
`INSTANT_VIEW_DOMAINS`	`i.` Telegram Instant View subdomains	`i.fxtwitter.com`
`GALLERY_DOMAINS`	`g.` gallery subdomains	`g.fxtwitter.com`
`FORCE_MOSAIC_DOMAINS`	`m.` mosaic subdomains	`m.fxtwitter.com`
`OLD_EMBED_DOMAINS`	`o.` legacy embed subdomains	`o.fxtwitter.com`

API Domains

Variable	Description	Example
`API_HOST_LIST`	FxTwitter API host(s)	`api.fxtwitter.com`
`BLUESKY_API_HOST_LIST`	FxBluesky API host(s)	`api.fxbsky.app`
`GENERIC_API_HOST_LIST`	Generic (Mastodon) API host(s)	`api.fxembed.com`

Service Domains

Variable	Description
`MOSAIC_DOMAIN_LIST`	Mosaic image generation service endpoint(s)
`GIF_TRANSCODE_DOMAIN_LIST`	GIF transcoding service endpoint(s)
`VIDEO_TRANSCODE_DOMAIN_LIST`	Video transcoding service endpoint(s)
`VIDEO_TRANSCODE_BSKY_DOMAIN_LIST`	Bluesky video transcoding endpoint(s)
`POLYGLOT_DOMAIN_LIST`	Translation service endpoint(s)
`POLYGLOT_ACCESS_TOKEN`	Translation service access token
`TWITTER_ROOT`	Base Twitter/X URL for redirects

Sentry (Error Reporting)

Variable	Description
`SENTRY_DSN`	Sentry Data Source Name (leave empty to disable)
`SENTRY_AUTH_TOKEN`	Sentry authentication token for source maps
`SENTRY_ORG`	Sentry organization slug
`SENTRY_PROJECT`	Sentry project slug

Wrangler Configuration

The wrangler.toml file configures the Cloudflare Worker:

name = "fxembed"
account_id = "YOUR_ACCOUNT_ID"
main = "./dist/worker.js"
compatibility_date = "2026-04-11"
send_metrics = false

analytics_engine_datasets = [
  { binding = "AnalyticsEngine" }
]

[build]
command = "npm run build"

Key Settings

name: Worker name (appears in *.workers.dev URL)
account_id: Your Cloudflare Account ID
compatibility_date: Cloudflare Workers API compatibility date
analytics_engine_datasets: Remove this block if you don’t use Cloudflare Analytics Engine

Secrets

Some values should be set as Wrangler secrets rather than in .env or wrangler.toml:

wrangler secret put CREDENTIAL_KEY
wrangler secret put EXCEPTION_DISCORD_WEBHOOK

CREDENTIAL_KEY: Encryption key for credential storage
EXCEPTION_DISCORD_WEBHOOK: Discord webhook URL for exception notifications

Branding

Copy branding.example.json to branding.json to customize the appearance and behavior of each domain zone.

Each zone in the zones array defines:

{
  "name": "FxTwitter",
  "default": true,
  "domains": ["fxtwitter.com", "twittpr.com"],
  "provider": "twitter",
  "favicon": "https://example.com/favicon.ico",
  "redirect": "https://github.com/FxEmbed/FxEmbed",
  "color": "#6363ff",
  "activityIcons": {
    "default": "https://example.com/icon32.png",
    "svg": "https://example.com/icon.svg",
    "16": "https://example.com/icon16.png",
    "32": "https://example.com/icon32.png"
  }
}

Field	Description
`name`	Display name for this zone
`default`	Whether this is the default zone (only one should be `true`)
`domains`	Domains this zone applies to
`provider`	Content provider (`twitter`, `bluesky`, `tiktok`)
`favicon`	URL to the favicon served for this zone
`redirect`	Where bare domain visits redirect to
`color`	Theme color for embeds (hex)
`activityIcons`	Icon URLs at various sizes; `activityIcons` can also be an array for random selection