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FastSpring

FINANCEE-COMM
Velocity0.0

Merchant of record

fastspring.com ↗

FastSpring shipped a Sessions v2 API for headless checkout — a real opening to Stripe and Paddle's territory.

headless checkoutsessions apimerchant of recordlocalized paymentssubscriptionsdeveloper api
◆Current state
FastSpring's standout March release is the new Sessions v2 API: a programmatic surface for creating, modifying, and updating checkout sessions before redirecting buyers, with localized payment-options retrieval. Around it, the Order Details page got a full redesign (license-fulfillment management, deactivated-key visibility, consolidated lifecycle panels), and monthly refinement digests track a steady drip of fixes — currency expansion (PEN, PHP, MYR, VND), Pix and UPI on Managed Subscriptions, accessibility tweaks on Stacked/Embedded Checkout. A January advisory flagged a coupon-API breaking change (1,000-item cap on inline codes array, effective Feb 23).
◆Where it's heading
FastSpring is repositioning from a hosted-checkout-and-merchant-of-record vendor toward a more API-driven platform that can compete on the headless ergonomics that have made Stripe, Paddle, and Lemon Squeezy attractive to developer-led SaaS. The Sessions v2 API is the structural piece; the localization expansions and payment-method coverage (Pix, UPI, NOK PayPal, etc.) signal continued investment in non-US international payments where FastSpring has historically out-localized US-based competitors.
◆Prediction
Expect Sessions v2 to be followed by deeper webhook-based session lifecycle events and an Embedded Checkout SDK rebuilt on top of v2. The localization push should keep widening — likely adding more Latin American and Southeast Asian payment methods to match where SaaS revenue is growing fastest.

◆Recent moves

  1. 2mo ago

    March 2026 Refinements

    March monthly refinements: PEN currency support, fixes for zip code validation, subscription invoice payment handling, multi-discount coupon durations, quote price recalculation across currencies, Proration Estimate API tax/total bug, manual subscription SKU returns, and date translation fixes on the order list. The kind of consistent stability cleanup that a merchant-of-record platform needs to keep tax and pricing edge cases trustworthy.

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  2. 2mo ago

    Build dynamic checkout experiences via Sessions v2 API

    ⚡ SPARK

    Sessions v2 API gives sellers programmatic, granular control over checkout sessions: create/get sessions, dynamically add/update/remove cart items, push customer-data updates, and fetch localized payment options for the current cart. This is FastSpring's opening into the headless-checkout developer experience — the surface developers reach for when building custom buying flows on top of a merchant-of-record platform.

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  3. 3mo ago

    Redesigned Order Details page

    Order Details page got a full redesign: decluttered top-row, repositioned Actions panel, license-fulfillment management inline, deactivated-key visibility, dedicated Timeline/Tags/Notes/Emails/Webhooks panels, and clearer financial breakdowns for prorations and returns. Solid operator-experience overhaul for the merchant admin.

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  4. 4mo ago

    February 2026 Refinements

    February monthly refinements: PHP/MYR/VND currency support in Checkout, PayPal for NOK, Pix and UPI managed-subscription support, persistent input labels for accessibility, Stacked Checkout express-pay using last payment method, and fixes for Apple Pay name validation, $0 custom orders, subscription.updated webhook misfires, and address Line 2 / City retention on order moves. Heavy localization-and-subscriptions push.

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  5. 4mo ago

    Coupon API: codes array capped at 1,000 items (Feb 23 breaking change)

    Advisory: GET /coupons/{coupon_id} will cap the codes array at 1,000 items effective February 23, 2026 — integrations relying on larger inline lists must migrate to the paginated GET /coupons/{coupon-id}/codes endpoint. Performance hardening with reasonable migration runway, but a real breaking change for anyone managing coupons with massive code lists.

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  6. 4mo ago

    January 2026 Refinements

    January monthly refinements: Embedded Checkout mobile responsiveness, Stacked Checkout error banner placement, Google/Apple Pay company-field validation, Toss Pay test-mode handling, dashboard query performance, no-data chart states, custom-tag order reports, /coupons endpoint timeout fixes for million-code lists, manual-subscription update/proration via API. Steady operator-experience and developer-API hardening.

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