Contractor and open source contributions on record, so your code is yours or your company's, without ambiguity.
A developer's ownership story is written in commits, PRs, contractor invoices and employment agreements. Any one of them can quietly reassign work, or fail to reassign work that should have been assigned.
For solo developers, the risk is losing rights they thought were theirs. For companies, the risk is discovering during diligence that a key module was written by a contractor who never signed IP assignment.
Upload the contract, the repo licence and the list of dependencies.
Deed flags assignment gaps, incompatible licences and moonlighting clauses that overreach.
Contractor assignment, side project carve outs and dual licensing done in signed form.
A verifiable record when a client, an acquirer or an auditor asks who wrote what and under what terms.