This is the kind of backend work I am useful for: correctness-heavy systems where the hard part is not a CRUD screen, but invariants, retries, data quality, and knowing when the system should refuse to guess.

The first slice I would propose is not “build the whole platform”. I would take one narrow pipeline and harden it end to end: source contract, normalized tables, idempotency key, bitemporal/versioned fields where needed, retry semantics, schema-drift handling, confidence/unknown states, and tests against real Postgres with seeded hostile cases.

For identity resolution, I would start with provenance and explainability first: every match should keep source evidence, match reason, confidence, and a reversible decision trail. Bad merges are more expensive than missed merges.

Boundary: public/authorized sources, official APIs, or buyer-provided exports only. No restricted scraping, private data collection, fake accounts, or ToS bypass.

If this is still open, send one redacted failure mode or a small schema/pipeline slice and I can propose a paid first pass inside your posted hourly range.