1. Can you cite tangible accomplishments where your work has disproportionately benefited the business? Did something really cool technically != did something that made the company more money or cut costs. If not, avoid asking until you figure out how to meet this requirement.
2. Are you working for an established organization where raises are done on a schedule (and have been on a schedule for years)? If so, you may be better off having the conversations to condition your boss towards a bigger raise in April rather than demanding one now.
3. Do you have data? Don't think you're less than the market value, come with data. StackOverflow has done developer compensation surveys in the past, and there's always Glassdoor, etc.
Unless you have demonstrably had a positive impact on the business that went over and beyond expectations for an engineer, you may wish to wait until April and see how raises shake out then. If, however, you can come with data and make a case that you're going beyond the call of duty in your role (something that you could also show to a new prospective employer in an interview), give it a shot.