The verdict in three sentences
For a logistics scale-up in New York or Paris, a partner-facing public API (documented REST, keys, quotas, webhooks) costs EUR 30,000 to 70,000 in 2026 (about USD 32,000 to 76,000), and a developer portal adds EUR 10,000 to 20,000. A realistic timeline is 3 months with OAuth 2.0 security and full request logging. Payback is quick: around 40% of tracking support tickets disappear once customers query your shipment statuses directly.
A detailed partner API budget
A public API is not an internal API exposed as-is. It needs a stable contract, versioning, usage limits and documentation that a customer's developer can follow without calling you.
| Component | Scope | Budget (2026 ballpark) |
|---|---|---|
| Contract design | Resources, OpenAPI 3.1 spec, versioning | EUR 4,000 to 8,000 |
| Business endpoints | Shipments, statuses, labels, rates, 15 to 30 endpoints | EUR 12,000 to 30,000 |
| Authentication | OAuth 2.0 client credentials, key rotation, scopes | EUR 4,000 to 9,000 |
| Quotas and rate limiting | Limits per client and plan, 429 responses, usage dashboard | EUR 3,000 to 7,000 |
| Webhooks | Subscriptions, HMAC signatures, replay, queue | EUR 4,000 to 9,000 |
| Logging and monitoring | Per-request logs, alerts, 12-month retention | EUR 3,000 to 7,000 |
| Developer portal | Interactive docs, sandbox, sign-up, self-service keys | EUR 10,000 to 20,000 |
The low end covers about ten read-only endpoints and simple webhooks. The high end covers shipment creation via API, several pricing plans and a full test environment.
Build, buy a gateway, or combine
| Option | Upfront cost | Annual cost | Timeline | Main limit |
|---|---|---|---|---|
| Custom API without gateway | EUR 30,000 to 50,000 | EUR 6,000 to 10,000 | 10 to 12 weeks | Quotas and portal to build |
| Custom + managed gateway (AWS, Kong) | EUR 35,000 to 60,000 | EUR 8,000 to 20,000 | 10 to 12 weeks | Usage cost at high volume |
| Full API platform (Apigee, MuleSoft) | EUR 40,000 to 80,000 | EUR 30,000 to 100,000 | 4 to 6 months | Oversized below 100 partners |
| One-off connectors per customer | EUR 5,000 to 15,000 each | Maintenance multiplied | 3 to 6 weeks each | Fast technical debt |
Below 100 integrated partners, a custom API with a managed gateway offers the best value. Beyond 5 one-off connectors, a public API becomes cheaper than piling up bespoke integrations.
Security and compliance: what belongs in the spec
Require OAuth 2.0 with short-lived tokens (15 to 60 minutes), separate read and write scopes, signed webhooks, TLS 1.2 minimum and timestamped logs kept 12 months. Recipient data (name, address, phone) is personal data under GDPR and US state privacy laws: the API must filter fields by partner. Budget a 3 to 5-day penetration test before launch, EUR 4,000 to 8,000.
Mini case study
Sarah, CTO of a logistics scale-up in New York, receives 2,500 tickets a month, 1,100 of them about shipment tracking. With an API and status webhooks, 40% of those tickets disappear: 440 tickets a month. At 12 minutes per ticket and EUR 38 loaded hourly cost, the gain is 440 × 0.2 h × EUR 38 = EUR 3,344 a month, or EUR 40,100 a year. An API at EUR 50,000 plus a portal at EUR 15,000 pays back in 19 months on support alone, and sooner if it helps close two enterprise accounts that required an integration.
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FAQ
REST or GraphQL for a partner API?
REST remains the standard expected by 80 to 90% of customer teams and tools such as ERPs. GraphQL is justified for advanced technical partners, at 15 to 25% extra development cost.
Should API access be charged?
It is common in logistics: free up to a quota (for example 10,000 calls a month), then plans at EUR 200 to 1,000 a month. Plan management adds EUR 3,000 to 7,000.
How much does a public API cost to maintain?
Allow 15 to 20% of the initial budget a year, EUR 6,000 to 14,000, because every change must stay compatible with the versions partners use.
How long until a first partner is in production?
A beta with 5 to 8 endpoints can open to a pilot partner in 6 to 8 weeks, with the full version around week 12.
Can documentation be generated automatically?
Yes, from the OpenAPI spec. You still need 3 to 5 days of writing for quick-start guides, examples and error codes.
Let's scope your project. List the resources to expose, your priority partners and your security requirements, and we will price an API between EUR 30,000 and 70,000 deliverable in 3 months. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.
Mohamed Bah
Fondateur, Kolonell
Passionate about digital and entrepreneurship in Africa, Mohamed has been helping Sénégalese businesses with their digital transformation since 2020. Founder of Kolonell, he believes every SME deserves a professional and accessible online présence.
