tsugi-kpool (tsugiai-kpool-sdk)
Copyright 2026 TsugiCinema, Inc.

This product includes software developed by TsugiCinema, Inc. and is
licensed under the Apache License, Version 2.0 (see LICENSE).

PATENT-ALIGNED SDK. The Apache-2.0 patent grant in Section 3 extends
to TsugiCinema's K-Pool LoRA (US App. 64/060,315, filed 2026-05-07)
and Infinity (US App. 64/055,093, filed 2026-05-01) patent estates AS
PRACTICED BY THE SDK CODE AS DISTRIBUTED. Apache-2.0 Section 3's
"necessarily infringed by their Contribution" language bounds the
patent license to the specific embodiment present in the SDK code,
not the broader scope of the patent claims as filed. See LICENSE for
the full NOTICE preamble.

This SDK exercises the following patent claim elements:

  - K-out-of-N adapter routing (K-Pool LoRA claim element)
  - Adapter-gradient elastic buffer (software analog of Infinity claim 2)
  - Buffer-convergence aggregation trigger (Infinity claim 4)
  - Phase-correction sideband (Infinity claim 3)

This software composes with public prior art from the following
sources. The implementation here is original TsugiCinema, Inc. code.

1. Low-Rank Adaptation of Large Language Models.
   Hu, E. J. et al. (2021). arXiv:2106.09685.
   The LoRA adapter shape and field semantics are anchored on the LoRA
   paper and the peft library's LoraConfig.

2. PEFT (Parameter-Efficient Fine-Tuning).
   HuggingFace (2022-present). https://github.com/huggingface/peft
   This SDK extends peft's LoraConfig with K-Pool routing and Infinity
   sideband fields, and uses peft's adapter discovery and routing
   primitives.

3. Decoupled DiLoCo: Continual Pre-Training of Language Models without
   Aggregator Synchronization.
   Douillard, A.; Donchev, A.; Rush, A.; Riedel, S. (2026).
   arXiv:2604.21428.
   The variance-threshold buffer-convergence trigger is the DI-4
   distinguishing argument versus Decoupled DiLoCo's time/quorum-based
   aggregation trigger. The SDK's trigger contrast with Decoupled
   DiLoCo's Algorithm 2 is documented in docs/architecture.md.

COMPANION SDK:

A companion SDK at github.com/tsugiai/tsugi-mend
("tsugiai-mend-sdk") is also licensed under Apache-2.0 but is
patent-independent by deliberate construction: it does NOT exercise
either of TsugiCinema's K-Pool LoRA or Infinity patent estates. The
two SDKs share zero code. The unified product surface (`pip install
tsugi`) wraps both SDKs at a packaging level.
