there was a crowdsourced  vaccine,   
  that could  be created regionally by  
    most   pharmaceutical  companies    
  without much  effort,  and  it  was   
   estimated   that   it  had  saved    
      tens      of      millions.       
                                        
 but it was  not officially recognized by 
 the world  health organization,  and  as 
 such did  not  give what the  sanctioned 
 (and   unobtainable)   ones   did:   the 
 subskin chip  that would  let you  enter 
       (or      leave)     cities.      
                                        
  and that's why, eventually, we would  
   create our  own chips.  they  were   
  larger than the official ones, and a  
   little   unstable,   and   needed    
    maintenance.  but  they   worked!   
  or, they would work  together with a  
  little something  to make the guard   
      look    the     other    way.     
                                      
                                      
                                          
    but the scanner showed green, so...