If you're new to this: All of the open source models are playing benchmark optimization games. Every new open weight model comes with promises of being as good as something SOTA from a few months ago then they always disappoint in actual use.
I've been playing with Qwen3-Coder-Next and the Qwen3.5 models since they were each released.
They are impressive, but they are not performing at Sonnet 4.5 level in my experience.
I have observed that they're configured to be very tenacious. If you can carefully constrain the goal with some tests they need to pass and frame it in a way to keep them on track, they will just keep trying things over and over. They'll "solve" a lot of these problems in the way that a broken clock is right twice a day, but there's a lot of fumbling to get there.
That said, they are impressive for open source models. It's amazing what you can do with self-hosted now. Just don't believe the hype that these are Sonnet 4.5 level models because you're going to be very disappointed once you get into anything complex.
I've been playing with Qwen3-Coder-Next and the Qwen3.5 models since they were each released.
They are impressive, but they are not performing at Sonnet 4.5 level in my experience.
I have observed that they're configured to be very tenacious. If you can carefully constrain the goal with some tests they need to pass and frame it in a way to keep them on track, they will just keep trying things over and over. They'll "solve" a lot of these problems in the way that a broken clock is right twice a day, but there's a lot of fumbling to get there.
That said, they are impressive for open source models. It's amazing what you can do with self-hosted now. Just don't believe the hype that these are Sonnet 4.5 level models because you're going to be very disappointed once you get into anything complex.