Your store grows - and so do hidden costs. Estimate your five-year TCO.
A quick, free calculator based on 2026 market assumptions. See when a move to headless (Medusa.js) starts to pay off at your GMV level.
- Models informed by 16+ years in software delivery and 120+ shipped digital projects.
- Teams like SFD (100k+ app downloads, Mobile Trends Awards 2025 nomination), EMKA S.A., and Berg System work with us.
- Unlike many agencies, we offer a fixed-price guarantee after the DDT (Discovery, Design & Technology) stage.
TCO calculator
Cost on SaaS platform
Estimated five-year total
≈ 3.45 M PLN
Headless e-commerce (Medusa.js)
Estimated five-year total
≈ 1.15 M PLN
Five-year cost structure at GMV: 15 million PLN
Your SaaS bill
- Platform subscription and plans
- 413,970 PLN
- Payment fees and revenue shareUsually the dominant line - it scales with GMV.
- 1,974,684 PLN
- Paid marketplace apps and integrations
- 1,061,096 PLN
Your headless investment (Medusa.js)
- Implementation (CAPEX)
- 338,531 PLN
- No extra platform turnover fees (beyond card processing)
- 0 PLN
- Run costs: SLA, hosting, audits
- 811,469 PLN
Red flag
You are overpaying to scale: transaction fees and apps tax growth harder than running your own stack would.
Estimated five-year savings:
You keep about 2,299,750 PLN PLN in the business (66.7% lower vs SaaS).
What does saving 2.3 million PLN mean in practice for your company?
Expansion budget
Fund a safer rollout into two or three new international markets instead of feeding the same line items to the platform.
Keep the team funded
Roughly covers a five-person R&D or e-commerce squad for close to two years while you still ship product improvements.
Performance marketing
Reallocate budget to paid acquisition and lifecycle campaigns instead of ever-rising payment fees and app subscriptions.
Payback moment (break-even)
Month 22
From this month onward, cumulative headless spend stays at or below cumulative SaaS spend at the same volume - every month after that widens the gap in your favor.
How costs add up over time (cumulative)
Curves illustrate a typical pattern: SaaS climbs faster due to fees and apps; headless starts higher (CAPEX) then grows more gently (OPEX).
This is a directional marketing model, not a commercial quote. Real TCO needs a process and migration roadmap review.
Non-financial upside of going custom (Medusa.js)
SaaS pain is not only cash - it is friction: API ceilings, support queues, and roadmap items that never get approved.
For engineering leadership
Stop hacking around Shopify API limits. Open code (Next.js + Medusa.js), data ownership, and an architecture engineers want to extend - not another SaaS workaround.
For marketing and e-commerce
Ship subscription models, bespoke B2B pricing, or 3D configurators without waiting on paid App Store plugins or template vendor timelines.
Edge assumptions behind the algorithm (for skeptics)
Transparent simplifications in the demo model. A real quote always needs contracts, gateway rates, and integration maps.
- For SaaS we model an effective blended gateway fee around 2.15% plus a small per-order fixed (on the order of USD 0.30) averaged into the reference curve.
- For headless we assume no extra platform take-rate on turnover (beyond card-network/processor costs and your infra).
- Medusa.js CAPEX steps between scale tiers (build + integrations), it does not grow linearly with every GMV million.
Let us map your exit from SaaS
Book a free 45-60 minute strategy session with a GMI e-commerce architect. You leave with specifics even if we never sign a build contract.
- A focused TCO pass on your real volumes and payment-gateway fees - not generic industry tables.
- Migration risk notes and a starter Medusa.js rollout timeline that keeps sales running (dual run, phased cutover).
- A straight answer on whether a fixed-price guarantee after our DDT (Discovery, Design & Technology) stage fits your case.
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