\startluacode
	fonts.handlers.otf.addfeature {
		name = "kernit",
		type = "kern",
               nocheck = true,
		data = {
                     [0x27E8] = { ["f"] = 300, ["fi"] = 300, ["fl"] = 300 }
		}
	}
\stopluacode
\definefontfeature[kernit][mode=node,kernit=yes]

\starttext
\definedfont[name:ebgaramondregular*default,kernit]

⟨f ile

⟨f lame

⟨file

⟨flame

\definedfont[name:ebgaramonditalic*default,kernit]

⟨f ile

⟨f lame

⟨file

⟨flame

\stoptext