CRMEUInvoicing-first CRM from France — connected through its own developer portal, with access scoped to exactly what's needed
Sellsy grew out of French invoicing software and still keeps billing at its center, alongside contacts, deals and support tickets. Its connection interface lives inside its own developer portal, where every connection gets its own scoped-down access — so it only ever touches the parts of the account it actually needs.
Before a bookkeeper copies the invoice into another accounting tool by hand at the end of the week.
After a connection with the right scoped access pushes the same invoice into that tool automatically, the moment it's created.
Before a connection is given full account access by default, more than the task actually calls for.
After access is scoped down to just what that specific connection needs, so everything else in the account stays out of reach.
Before a long payment schedule keeps growing past what a single subscription can hold, and nobody notices until something fails.
After knowing the 500-installment ceiling upfront, we design the schedule to split across subscriptions before it ever hits the wall.
Before an old connection quietly stops getting fixes, since its version no longer receives updates on its own.
After we route it through the current interface with the matching access enabled, so it keeps working and benefits from what's actively maintained.
For those who want to check: each point links to the official documentation page it comes from.
Sellsy has a public REST API (version 2), and the vendor keeps its changelog open, with dated release notes.
Source: docs.sellsy.com ↗ checked 2026-09-25Access for a connection is created inside the account's own settings, in a section called the Developer Portal.
Source: help.sellsy.com ↗ checked 2026-09-25There are three access types: public — reserved for companies with a formal arrangement with Sellsy, for security reasons — personal, for server-to-server use, and private, for client-to-server use.
Source: help.sellsy.com ↗ checked 2026-09-25Access rights can be limited through separate permissions: either every action is enabled, or only the specific ones a connection actually needs.
Source: help.sellsy.com ↗ checked 2026-09-25The older version of the interface (v1) can still be used, but only through the current v2 access with the matching permission enabled — v1 itself no longer gets separate updates.
Source: help.sellsy.com ↗ checked 2026-09-25One documented ceiling: a single subscription can hold at most 500 scheduled payment installments — a longer payment plan has to be split across more than one subscription. Sellsy's docs don't publish a general numeric request-rate limit.
Three steps from a first message to work on your project.
Describe the task in the form — in text or by voice. Budget and timing are optional.
A developer studies the brief, asks about anything unclear and sends an estimate.
Once scope and price are agreed, the work begins.
or write to info@coreviaflow.space
Describe the task in text or a voice message. We look at your setup and reply with a plan.
Four services people come to us for most often. Each page explains what we do, how the work goes and where to start.
Choose the system, set up the pipeline, migrate data, train the team.
Learn more →Accounting, telephony, website, payments and messengers feed the CRM on their own.
Learn more →Orders, requests and answers around the clock, straight into your CRM.
Learn more →Flows between CRM, email, spreadsheets, payments and AI, on your own server.
Learn more →
CRMEUModular ERP and CRM that grows app by app — connect it to everything else your business runs without losing that flexibility
See scenarios →
CRMEUCRM, projects and invoicing in one system — built to be connected by developers, not dragged and dropped
See scenarios →
CRMEUThe deal-focused CRM: connect it once, and deals, contacts and follow-ups keep themselves in sync
See scenarios →
CRMUSUS CRM with built-in calling and no-code automation, ready to plug into the tools you already run
See scenarios →
Payments & POSEUEuropean payment methods connected straight to the order that's waiting on them
See scenarios →
CRMUAUkrainian CRM that pulls orders from your site, marketplaces and chat apps into one pipeline
See scenarios →Implementation · Development · Integrations →
Sellsy is a trademark of its owner. CoreviaFlow is not affiliated with it unless stated otherwise. Screenshots are taken from public vendor materials; the source is shown under each one.
