Composer and DeepSeek V3.1 Terminus don't publish scores on any of the same benchmarks, so there's no direct head-to-head comparison. DeepSeek V3.1 Terminus shipped 37 days before Composer, so benchmark comparisons should account for the intervening progress.

Composer is proprietary, while DeepSeek V3.1 Terminus is open weight.

Direct benchmark comparisons are unavailable — Composer and DeepSeek V3.1 Terminus don't publish scores on any of the same benchmarks.