The version history of the proprietary scripts and rule sets, the internal procedure manuals, the specialist's training and project records, the technical lead's statement on knowledge distribution, the ownership registers and the payroll for the qualifying year. The letter is written last so it can cite them.
Collect the evidence, then let the letter point to it
Hypothetical example: the firm's manager offers to write a strong support letter immediately. Ask her to wait. First export the repository history showing the specialist as author of the classification rule sets and quality-control scripts, the internal procedure manual with its revision dates, and the training records showing the specialist taught the workflow to others.
Obtain the technical lead's signed statement on how many employees can run the workflow and how long it took to develop. Assemble the share registers and ownership chart for the two firms, evidence that both are operating, and the specialist's payroll for the continuous qualifying year. If the specialist will work at a client's office, add the services agreement showing the affiliate's control.
Provide certified English translations for any French material. With those in hand, the support letter can cite an exhibit for every claim, which is what makes it persuasive. Organize the evidence so a reader can move from a claimed method to the document that supports it and to the proposed task requiring it.
Version histories, restricted manuals, training records, and client deliverables can be more persuasive than a résumé alone. Hypothetical example: a public-transit analytics company relies on a specialist who knows an internal delay-prediction model. The reviewer obtains release notes, access controls, and a project plan showing why the U.S.
team needs that model, while removing material unrelated to the assignment. The sequence reduces the risk that a large technical appendix obscures the actual issue.