Jorge Aguilera, who was sentenced to 120 months in prison after a jury found him guilty of drug offenses, see United States v. Aguilera, 625 F.3d 482, 484-85 (8th Cir. 2010), appeals the district court’s 1 order denying his 28 U.S.C. § 2255 motion *630 after an evidentiary hearing. The district court granted Aguilera a certifícate of ap-pealability on his claim that his counsel was ineffective for having him provide a written proffer for safety-valve relief, rather than having him submit to an interview.

Upon de novo review of the district court’s denial of this ineffective-assistance claim, and clear-error review of underlying factual findings, see Covey v. United States, 377 F.3d 903, 906 (8th Cir. 2004), we agree with the court that the decision of trial counsel not to subject Aguilera to a potentially prejudicial and likely futile proffer interview was a virtually unchallengeable matter of strategy, see Forsyth v. Ault, 537 F.3d 887, 892 (8th Cir. 2008), and Aguilera failed to show that he suffered resulting prejudice. We therefore affirm the judgment of the district court, and we grant counsel’s motion to withdraw.