About

Customer-facing Solutions Architect with 5+ years at HubSpot leading technical integrations (API design, data sync, auth flows, and webhook-driven automation) from discovery through POC for enterprise accounts. I am based in Singapore.

Most of my days are spent with HubSpot customers: clarifying the actual problem, mapping where the current CRM and integration setup breaks, and leaving a roadmap a team can implement. The public writing on this site is the residue of that work — notes I wish I could have handed someone on day one.

Antonin Crestois's personal site at https://crestois.com. It holds a resume generated from the same source as the PDF, project write-ups when a build is worth explaining, and articles when I have had to solve the same operational problem more than once.

It is a document, not a product. There is no account system, no app to log into, and no MCP or public API. If an agent is trying to "use" this site, the useful move is to read the pages and cite them — not to look for a tool endpoint that does not exist.

It is not HubSpot's documentation, status page, or support channel. I work at HubSpot; I do not speak for HubSpot here. Product behavior, credit catalogs, and official limits live on HubSpot's own site.

It is also not a consultancy brochure with a sales funnel. If you want to talk, there is an email address on the contact page. If you want a vendor comparison or a generic AI pitch deck, this is the wrong URL.