Measurements of the metal content of the circumgalactic medium (CGM) from the era of the first galaxies to the present day are key to understanding how metals are redistributed by outflows over cosmic time. Spectra of small numbers of background z~6 quasars have revealed intervening CIV absorbers tracing enriched gas deposited into the CGM of z >~ 5 galaxies by stellar outflows. However, larger samples are required to robustly quantify the distribution of absorber properties and track the chemical evolution history of the CGM. I will present exciting new results from the ESO large program XQR-30 which has quadrupled the number of high S/N z~6 quasar spectra, enabling much more precise measurements of the properties of CIV absorbers at z >~ 5. I will compare our measurements to predictions from simple enrichment models as well as state-of-the-art cosmological simulations, and discuss implications for the formation redshifts of the first galaxies and the properties of stellar feedback at high redshift.
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