design: Cryptic-seq was performed as previously described in PRJNA1167015 with the following modifications: HEK293attB gDNA sheared in a ME220 focused-ultrasonicator (Covaris) to an average fragment length of approximately 350-500 bp. End prep and dA tailing of the gDNA was performed by using NEBNext Ultra II DNA Library Prep Kit for Illumina (E7645L) as protocol instructed, after which Illumina TruSeq sequencing annealed Y adaptors containing 8bp UMIs were ligated to gDNA listed below. Two independent cryptic-seq reactions with the following pools of cryptic-seq donor plasmids were performed. Reaction 1 contains the following plasmids at equimolar ratios: PL2327_AA, PL2341_TT, PL2337_GG, PL2332_CC, PL2339_TC, PL2335_GA, with a final total plasmid concentration of 30 nM. The plasmid pool was then reacted with 1 ug sheared/adapter-ligated gDNA and 1 uM Bxb1 integrase at 37C for 4h in a recombination buffer. Reaction 2 contains the following plasmids at equimolar ratios: PL2312_GT, PL2328_AC, PL2331_CA, PL2340_TG, PL2334_CT, PL2329_AG and was reacted under the same conditions as reaction described above.