Environment Variables

Web (apps/web)

Variable	Required	Default	Description
VITE_API_URL	No	""	Base URL of the API server. Empty means same origin. In local dev, Vite proxies /api to localhost:3001 so this is not needed.

API: serverless (api/v1/) and Fastify (apps/api-local)

Variable	Required	Default	Description
STELLAR_NETWORK	No	"testnet"	Selects the network the API talks to. Any value other than "mainnet" resolves to testnet. Controls which CONTRACT_ADDRESSES/STELLAR_NETWORKS entry (packages/shared/src/constants.ts) is used for every contract call the API makes.
DEFINDEX_VAULT_ID	No	""	Overrides the DeFindex vault contract address at runtime. When empty, the address from CONTRACT_ADDRESSES.testnet.defindex.vault in packages/shared/src/constants.ts is used. Blend and vault contract addresses are always sourced from constants.
PORT	No	3001	Fastify server port (local dev only).
ALLOWED_ORIGIN	No	"https://usemeridian.vercel.app"	CORS allowed origin for the Fastify server. Set to your frontend domain in production if running Fastify as a standalone server.
REDIS_URL	No	""	Redis URL for @fastify/rate-limit in apps/api-local (ioredis). Unset: in-memory store (single process); production: set for distributed rate limits.

Deploy scripts (scripts/)

These are shell environment variables read by scripts/deploy-testnet.sh and scripts/redeploy-blend-adapter.sh at deploy time, not application runtime variables, and not read from .env files.

Variable	Required	Description
DEPLOYER	Yes (both scripts)	A funded Stellar secret key. Pays transaction fees and signs setup calls only — disposable, does not need to be kept after the script finishes.
ADMIN	No (deploy-testnet.sh only)	A public key that becomes the deployed vault's permanent admin. Defaults to DEPLOYER's own address if unset (with a warning) — set explicitly to a separate, durable key for anything beyond a throwaway test, and required ahead of mainnet.
USDC_ID	No	Overrides the testnet USDC contract address the deployed adapter/vault is wired to.
BLEND_POOL_ID	No	Overrides the testnet Blend pool address the deployed BlendAdapter is wired to.
VAULT_ID	Yes (redeploy-blend-adapter.sh only)	The already-live vault contract ID to eventually point at the newly deployed adapter via set_adapter.

deploy-testnet.sh prints four contract IDs on success (VAULT_CONTRACT_ID, ROUTER_CONTRACT_ID, BLEND_ADAPTER_CONTRACT_ID, MUSDC_CONTRACT_ID) — these aren't environment variables the app reads either; VAULT_CONTRACT_ID and MUSDC_CONTRACT_ID need to be copied into CONTRACT_ADDRESSES/KNOWN_POOLS in packages/shared/src/constants.ts and packages/stellar-sdk-helpers/src/known-pools.ts respectively. See Testnet Deployment.

Vercel

Set environment variables in the Vercel dashboard under Project Settings > Environment Variables, or via the CLI:

vercel env add DEFINDEX_VAULT_ID

Variables prefixed with VITE_ are inlined at build time and exposed to the browser. Do not put secrets in VITE_ variables.

Local development

Create .env files at the package level if needed:

# apps/api-local/.env
PORT=3001
DEFINDEX_VAULT_ID=C...   # optional, leave empty to use the address in constants.ts

The Fastify server loads .env via the dotenv package on startup.