as far as I know, rye extract doesnt exist. rye malt needs to be mashed, but it does have enough diastatic power to convert itself. mashing isn't all that different from steeping though. just steep it in 1-2qts/lb @150-160F for 60mins. 30mins may not get full conversion, but you'll still get flavor/color from it, however there may be a slight haze from leftover starches. more water may stretch the enzymes too thin, but up to 4qt/lb may be ok for at least partial conversion.