Environment variables

Source: references/env.md. This is the same file the agent reads.

paymentsConfigFromEnv() (TS) and config_from_env() (Python) enable a provider when its required variables are set. *_ENV is sandbox (default) or production (live also accepted).

Provider	Required	Optional
eSewa	`ESEWA_PRODUCT_CODE`, `ESEWA_SECRET_KEY`	`ESEWA_ENV`, `ESEWA_INTENT_PRODUCT_CODE`, `ESEWA_INTENT_ACCESS_KEY`, `ESEWA_INTENT_BASE_URL` (production Intent host from eSewa)
Khalti	`KHALTI_SECRET_KEY`, `KHALTI_WEBSITE_URL`	`KHALTI_ENV`; `KHALTI_PUBLIC_KEY` for mobile SDK builds only
Fonepay	`FONEPAY_MERCHANT_CODE`, `FONEPAY_SECRET_KEY`	`FONEPAY_ENV`, `FONEPAY_USERNAME`, `FONEPAY_PASSWORD` (needed for txnVerification + Dynamic QR)
connectIPS	`CONNECTIPS_MERCHANT_ID`, `CONNECTIPS_APP_ID`, `CONNECTIPS_PRIVATE_KEY_PEM`	`CONNECTIPS_ENV`, `CONNECTIPS_APP_NAME`, `CONNECTIPS_APP_PASSWORD`
CyberSource SA	`CYBERSOURCE_PROFILE_ID`, `CYBERSOURCE_ACCESS_KEY`, `CYBERSOURCE_SECRET_KEY`	`CYBERSOURCE_ENV`, `CYBERSOURCE_CURRENCY` (NPR)
CyberSource REST (SDK)	`CYBERSOURCE_MERCHANT_ID`, `CYBERSOURCE_KEY_ID`, `CYBERSOURCE_SHARED_SECRET`
NPS	`NPS_MERCHANT_ID`, `NPS_SECRET_KEY`	`NPS_ENV`, `NPS_MERCHANT_NAME`, `NPS_API_USERNAME`, `NPS_API_PASSWORD`
IME Pay	`IMEPAY_MERCHANT_CODE`, `IMEPAY_USERNAME`	`IMEPAY_ENV`, `IMEPAY_PASSWORD`, `IMEPAY_MODULE`

.env.example (sandbox values that are public in provider docs; everything else blank):

APP_PUBLIC_URL=https://shop.example.com     # used to build return URLs; must be reachable by the payer's browser

ESEWA_ENV=sandbox
ESEWA_PRODUCT_CODE=EPAYTEST
ESEWA_SECRET_KEY=8gBm/:&EnhH.1/q
ESEWA_INTENT_PRODUCT_CODE=INTENT
ESEWA_INTENT_ACCESS_KEY=LB0REg8HUSw3MTYrI1s6JTE8Kyc6JyAqJiA3MQ==

KHALTI_ENV=sandbox
KHALTI_SECRET_KEY=                          # test-admin.khalti.com → Keys (login OTP 987654)
KHALTI_WEBSITE_URL=https://shop.example.com

FONEPAY_ENV=sandbox
FONEPAY_MERCHANT_CODE=NBQM                  # public dev sample from Fonepay's spec
FONEPAY_SECRET_KEY=a7e3512f5032480a83137793cb2021dc
FONEPAY_USERNAME=
FONEPAY_PASSWORD=

CONNECTIPS_ENV=sandbox
CONNECTIPS_MERCHANT_ID=
CONNECTIPS_APP_ID=
CONNECTIPS_APP_NAME=
CONNECTIPS_APP_PASSWORD=
CONNECTIPS_PRIVATE_KEY_PEM=                 # PKCS#8 PEM; "\n" escapes allowed

CYBERSOURCE_ENV=sandbox
CYBERSOURCE_PROFILE_ID=
CYBERSOURCE_ACCESS_KEY=
CYBERSOURCE_SECRET_KEY=

NPS_ENV=sandbox
NPS_MERCHANT_ID=
NPS_MERCHANT_NAME=
NPS_API_USERNAME=
NPS_API_PASSWORD=
NPS_SECRET_KEY=

IMEPAY_ENV=sandbox
IMEPAY_MERCHANT_CODE=
IMEPAY_USERNAME=
IMEPAY_PASSWORD=
IMEPAY_MODULE=

Rules:

Commit .env.example only. Production secrets live in the platform’s secret store (Vercel/Render/Fly env, wrangler secret put, AWS/GCP Secret Manager, Kubernetes secrets).
Never expose these to the client. In Next.js, no NEXT_PUBLIC_ prefix; in Vite, no VITE_ prefix; in Expo, no EXPO_PUBLIC_ prefix. The only value a client may hold is the Khalti public key for its mobile SDK.
Fail fast at boot when a provider is half-configured in production (e.g. *_ENV=production with a sandbox product code like EPAYTEST).