Tokyo's next few weeks belong to builders and hackathons, not big stages. The main draw, SusHi Tech Tokyo on May 20, 2027, is seven months out: the city government's flagship, which gathers the whole Japanese ecosystem and a large foreign contingent. Until then, try the +81Builders Tokyo Agent Hackathon on Oct 17 and Redpine's AI hackathon on Oct 23, plus Venture Café's weekly Thursday Gathering at CIC Tokyo.