Intel has recently open sourced hyperscan library under BSD license. It’s a high-performance non-backtracking NFA-based regex engine.
Features: ability to work on streams of input data and simultaneous multiple patterns matching. The last one differs from (pattern1|pattern2|...) approach, it actually matches patterns concurrently.
It also utilizes Intel’s SIMD instructions sets like SSE4.2, AVX2 and BMI.
The summary of the design and explanation of work can be found here.
It also has great developer’s reference guide with a lot of explanations as well as performance and usage considerations.
Small article about using it in the wild (in russian).