Vibe coding for purchasing managers in professional services.
You buy for a firm that sells hours: the subcontractors, the expert witnesses, the research databases, the software licences billed back to clients. The tension is that much of what you purchase is rebilled to a client under engagement terms you did not write, and a vendor you onboard may receive confidential client material as part of the job.
What is true about software in professional services before you write a prompt.
Agencies, consultancies, law firms and accounting practices sell time and expertise, and most of their software is a compromise: the practice management system, the time tracker, the client portal that nobody likes. Executives at these firms are building their own: a client dashboard, a proposal generator, an intake workflow, a utilisation report. Every one holds client confidential information.
Client confidentiality is the business
A tool that lets one client see another's project, or exposes a document to the wrong staff member, ends a relationship and possibly a licence. Access control per client is the first thing to build and the first thing to check.
The engagement letter has terms about data
Clients often specify where their data may be stored and who may process it. A tool on a personal hosting account in the wrong region breaches contracts the firm signed.
Billing must reconcile
Time, rates, expenses and invoices have to agree with the accounting system. A utilisation tool or a billing dashboard that drifts from the books causes arguments with clients and auditors.
Professional rules apply to software
Legal privilege, accounting standards and industry codes constrain how records are kept and who may access them. The tool has to fit those rules, not the other way round.
What a purchasing manager in professional services builds first.
01The subcontractor and expert engagement desk
Every outside expert, freelancer and subcontractor with their agreement, conflict check, rate and the client matter they are engaged on. Two matters cannot share a vendor without a partner seeing it first.
02The rebillable purchase tracker
Purchases tagged to a client matter at the moment they are made, so court fees, data subscriptions and travel land on the right invoice. Unbilled disbursements are pure margin leaking every month.
03The licence seat audit
Research databases and practice software seats compared against active staff and their utilisation. Firms routinely pay for seats belonging to people who left in the spring.
Purchasing managers in every industry tend to build the same four things. The purchasing manager page has that list.
Subcontractor records reveal which clients you serve
The engagement desk lists vendors by client matter, and the AI built one login with the whole list visible to any user. A subcontractor with an account sees which competitors' matters your firm is working on, and a staff member with no need to know sees a confidential merger by its code name. The engagement letter promised none of that would happen.
The pattern underneath is the one every purchasing manager hits: the dashboard has no login or one login for everyone. Negotiated rates, contract terms and supplier margins are one shared URL away from a competitor or a supplier's rival.
What a safe build in professional services usually runs on.
Builds run on a standard web stack with Postgres, private document storage, single sign-on for staff and a scoped client login, and integrations with the practice management, time and accounting systems through read-only keys where possible. Client-facing pages are separated from internal ones from the start.
What changes for a purchasing manager in professional services.
A CTO in your corner treats your procurement tool as a control, not a convenience. Approvals are enforced on the server where they cannot be skipped. ERP access is read-only until there is a reason for it not to be. Supplier documents are private and pricing is behind a login with roles. You still build the tool purchasing has needed for years. It just passes the audit it was built to help with.
What purchasing managers in professional services ask.
A CTO who has read professional services apps before yours.
Thirty minutes, free, no card. What you built, what is going on with it, whether we can help.
In your corner.