Update license headers, clean up README, clarify licensing of third party content (bench 5834033)

.dockerignore

@@ -1 +1,15 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 *

.gitattributes

@@ -0,0 +1,13 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.

.github/workflows/linux-release.yml

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 name: Linux release
 
 on:

.github/workflows/windows-release.yml

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 name: Windows release
 
 on:

.gitignore

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 # ---> Nim
 nimcache/
 nimblecache/

.gitmodules

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 [submodule "networks"]
 	path = networks
 	url = https://git.nocturn9x.space/heimdall-engine/networks

.pre-commit-config.yaml

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 repos:
   - repo: local
     hooks:

3rdparty/king_plane_buckets.txt

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 # Copied from src/heimdall/nnue.nim INPUT_BUCKETS.
 0,  1,  2,  3,  3,  2,  1,  0,
 4,  5,  6,  7,  7,  6,  5,  4,

AGENTS.md

@@ -1,3 +1,19 @@
+<!--
+Copyright 2026 Mattia Giambirtone & All Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
 # Working on Heimdall
 
 Heimdall is a UCI chess engine written in Nim, with NNUE evaluation and an
@@ -43,21 +59,98 @@ available. Choose tests relevant to the affected behavior:
   requires Python and Stockfish on `PATH`; see `python tests/suite.py -h` for
   explicit binary paths.
 - `make bench`: builds with `make dev` and runs the engine's search benchmark.
-  For performance work, compare baseline and candidate binaries built with the
-  same flags and network. Use `scripts/compare_performance.py` for repeated paired
-  measurements; confirm microbenchmark results with full search.
 
-Build standalone Nim tests through `make dev` as well. For example, to compare
-incremental NNUE evaluation with fresh evaluation:
+<!-- Testing documentation consolidated with assistance from AI agents. -->
+
+### Focused correctness tests
+
+Build standalone Nim tests through `make dev`, using `MAIN`, `EXE_BASE`, and an
+absolute `EVALFILE` path. Use `IS_TEST=1` for correctness checks and optimized
+default builds for speed measurements.
+
+Use focused tests for incremental/fresh NNUE evaluation, threat indexing,
+move-generation and state/hash invariants, and search limits. NNUE checks include
+pending updates, cloning, the 255-ply boundary, and all 960 castling arrangements
+for both colors:
 
 ```sh
 make dev MAIN=tests/test_nnue.nim IS_TEST=1 EXE_BASE=bin/test-nnue EVALFILE="$PWD/networks/files/gramr.bin"
 bin/test-nnue
+make dev MAIN=tests/test_movegen.nim IS_TEST=1 EXE_BASE=bin/test-movegen EVALFILE="$PWD/networks/files/gramr.bin"
+bin/test-movegen
+make dev MAIN=tests/test_limits.nim IS_TEST=1 EXE_BASE=bin/test-limits EVALFILE="$PWD/networks/files/gramr.bin"
+bin/test-limits
+make dev MAIN=tests/test_threat_index.nim IS_TEST=1 EXE_BASE=bin/test-threat-index EVALFILE="$PWD/networks/files/gramr.bin"
+bin/test-threat-index
+make dev MAIN=tests/test_threats.nim IS_TEST=1 EXE_BASE=bin/test-threats EVALFILE="$PWD/networks/files/gramr.bin"
+bin/test-threats
 ```
 
-Use the same `MAIN`/`EXE_BASE`/absolute `EVALFILE` pattern for other Nim tests or
-benchmarks in `tests/`. Use `IS_TEST=1` for correctness checks and optimized
-default builds for speed measurements. See `README.md` for more testing details.
+The threat-index test checks every table entry against geometric attacks and
+explicit exclusion rules, verifies the color bounds, and checks retained feature
+indices for collisions and overflow. It also checks both indexers across perspectives
+and mirroring, and verifies the perspective masks. The threat-collection test compares
+runtime attacks and collected features against independent board geometry, including
+friendly pawn defenses, writable output slices, and positions before and after special
+moves and undo. Fixed expected indices from Viridithas additionally verify both
+perspectives of the starting position and Kiwipete.
+
+To check the scalar NNUE path, repeat its build with
+`AVX2_SUPPORTED=0 AVX512_SUPPORTED=0 VNNI_SUPPORTED=0`; the diagnostic prints
+the selected backend. Native builds append SIMD defines after `EXTRA_NFLAGS`,
+so `EXTRA_NFLAGS=-u:simd` alone does not select the scalar path.
+
+`tests/test_alloc.nim` checks allocation alignment. Add `EXTRA_NFLAGS=-d:noTHP`
+to its build to exercise the allocator without huge-page advice; the same flag
+can be used with the NNUE test.
+
+### Performance comparisons
+
+For performance comparisons, build separate baseline and candidate executables
+with identical flags and network, then alternate runs on one CPU:
+
+```sh
+python scripts/compare_performance.py bin/baseline bin/candidate --cpu 2 --pairs 12 --perf --output comparison.json
+```
+
+The script checks node counts and saves paired timings, hardware counters and a
+bootstrap interval. Omit `--perf` if hardware counters are unavailable. Use
+`--mode perft --depth 7` for movegen comparisons. `tests/bench_nnue.nim` and
+`tests/bench_setup.nim` provide separate inference and worker-setup benchmarks;
+build them with the same `MAIN`/`EVALFILE` pattern. Measure optimized builds for
+speed and use `IS_TEST=1` for correctness checks. Confirm microbenchmark gains
+with full search: a repeated NNUE input corpus can hide branch-prediction costs.
+
+For real UCI node/time budgets on a selected FEN corpus, use `--mode uci`:
+
+```sh
+python scripts/compare_performance.py bin/baseline bin/candidate --mode uci --positions src/heimdall/resources/misc/bench.txt --count 24 --offset 1 --stride 2 --limit-kind nodes --limit 200000 --cpu 2 --pairs 8 --perf --output comparison-uci.json
+```
+
+Use `--limit-kind time --limit 200` for 200 milliseconds per position. UCI NPS
+uses the summed final search node/time reports, excluding engine startup and
+position resets; raw results also record whole-process wall time. Fixed-node,
+single-thread comparisons require matching per-position nodes, depths and best
+moves. Timed and multithreaded searches do not have identical trees and are not
+playing-strength tests. `--count`, `--offset` and `--stride` select distinct,
+normalized FENs; too-short or incomplete searches are rejected.
+
+### Profile-guided compilation
+
+Optional profile-guided compilation is available through the same dev target:
+
+```sh
+make dev PGO=1 EXE_BASE=bin/heimdall-pgo
+```
+
+This needs Python and a matching `llvm-profdata` installation. It builds an
+instrumented engine, trains with node and time budgets, merges the profiles, and
+rebuilds using them. The default training set is 24 even-indexed positions from
+the built-in benchmark corpus; the odd-indexed selection above is held out.
+The ordinary full benchmark includes training positions, so it is not a held-out
+PGO validation. Profile artifacts stay in ignored `build/pgo/`. Override
+`PGO_DIR`, `PGO_POSITIONS`, `PGO_TRAIN_ARGS`, `PGO_TRAIN_NODES`, or `PGO_TRAIN_MSEC`
+to customize training. Normal dev and OpenBench builds do not enable PGO.
 
 ## Project layout
 

Dockerfile

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 # By @agethereal. Thanks Andy!
 FROM ubuntu:24.04
 

Makefile

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 .DEFAULT_GOAL := openbench
 
 .SUFFIXES:

README.md

@@ -1,3 +1,19 @@
+<!--
+Copyright 2026 Mattia Giambirtone & All Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
 ![Heimdall](Heimdall_logo_v2.png "Heimdall")
 
 [![Ask DeepWiki](https://deepwiki.com/badge.svg)](https://deepwiki.com/nocturn9x/heimdall)
@@ -57,96 +73,10 @@ All of the targets require a 64 bit processor: Heimdall does not (and will never
 
 ## Testing
 
-For a quick regression pass with the installed dependencies and network, run
+For a quick regression pass with dependencies and network weights installed, run
 `make dev` followed by `python -m unittest discover -s tests -p 'test_*.py'`.
-The Python tests cover UCI handling and test/benchmark tools. Set `HEIMDALL` to
-test a different engine binary, for example after building with
-`make dev IS_TEST=1 EXE_BASE=bin/testdall` to enable runtime checks.
-
-Use focused tests for incremental/fresh NNUE evaluation, threat indexing,
-move-generation and state/hash invariants, and search limits. NNUE checks include
-pending updates, cloning, the 255-ply boundary, and all 960 castling arrangements
-for both colors:
-
-```sh
-make dev MAIN=tests/test_nnue.nim IS_TEST=1 EXE_BASE=bin/test-nnue EVALFILE="$PWD/networks/files/gramr.bin"
-bin/test-nnue
-make dev MAIN=tests/test_movegen.nim IS_TEST=1 EXE_BASE=bin/test-movegen EVALFILE="$PWD/networks/files/gramr.bin"
-bin/test-movegen
-make dev MAIN=tests/test_limits.nim IS_TEST=1 EXE_BASE=bin/test-limits EVALFILE="$PWD/networks/files/gramr.bin"
-bin/test-limits
-make dev MAIN=tests/test_threat_index.nim IS_TEST=1 EXE_BASE=bin/test-threat-index EVALFILE="$PWD/networks/files/gramr.bin"
-bin/test-threat-index
-make dev MAIN=tests/test_threats.nim IS_TEST=1 EXE_BASE=bin/test-threats EVALFILE="$PWD/networks/files/gramr.bin"
-bin/test-threats
-```
-
-The threat-index test checks every table entry against geometric attacks and
-explicit exclusion rules, verifies the color bounds, and checks retained feature
-indices for collisions and overflow. It also checks both indexers across perspectives
-and mirroring, and verifies the perspective masks. The threat-collection test compares
-runtime attacks and collected features against independent board geometry, including
-friendly pawn defenses, writable output slices, and positions before and after special
-moves and undo.
-
-To check the scalar NNUE path, repeat its build with
-`AVX2_SUPPORTED=0 AVX512_SUPPORTED=0 VNNI_SUPPORTED=0`; the diagnostic prints
-the selected backend. Native builds append SIMD defines after `EXTRA_NFLAGS`,
-so `EXTRA_NFLAGS=-u:simd` alone does not select the scalar path.
-
-For performance comparisons, build separate baseline and candidate executables
-with identical flags, then alternate runs on one CPU:
-
-```sh
-python scripts/compare_performance.py bin/baseline bin/candidate --cpu 2 --pairs 12 --perf --output comparison.json
-```
-
-The script checks node counts and saves paired timings, hardware counters and a
-bootstrap interval. Omit `--perf` if hardware counters are unavailable. Use
-`--mode perft --depth 7` for movegen comparisons. `tests/bench_nnue.nim` and
-`tests/bench_setup.nim` provide separate inference and worker-setup benchmarks;
-build them with the same `MAIN`/`EVALFILE` pattern. Measure optimized builds for
-speed and use `IS_TEST=1` for correctness checks. Confirm microbenchmark gains
-with full search: a repeated NNUE input corpus can hide branch-prediction costs.
-
-For real UCI node/time budgets on a selected FEN corpus, use `--mode uci`:
-
-```sh
-python scripts/compare_performance.py bin/baseline bin/candidate --mode uci --positions src/heimdall/resources/misc/bench.txt --count 24 --offset 1 --stride 2 --limit-kind nodes --limit 200000 --cpu 2 --pairs 8 --perf --output comparison-uci.json
-```
-
-Use `--limit-kind time --limit 200` for 200 milliseconds per position. UCI NPS
-uses the summed final search node/time reports, excluding engine startup and
-position resets; raw results also record whole-process wall time. Fixed-node,
-single-thread comparisons require matching per-position nodes, depths and best
-moves. Timed and multithreaded searches do not have identical trees and are not
-playing-strength tests. `--count`, `--offset` and `--stride` select distinct,
-normalized FENs; too-short or incomplete searches are rejected.
-
-Optional profile-guided compilation is available through the same dev target:
-
-```sh
-make dev PGO=1 EXE_BASE=bin/heimdall-pgo
-```
-
-This needs Python and a matching `llvm-profdata` installation. It builds an
-instrumented engine, trains with node and time budgets, merges the profiles, and
-rebuilds using them. The default training set is 24 even-indexed positions from
-the built-in benchmark corpus; the odd-indexed selection above is held out.
-The ordinary full benchmark includes training positions, so it is not a held-out
-PGO validation. Profile artifacts stay in ignored `build/pgo/`. Override
-`PGO_DIR`, `PGO_POSITIONS`, `PGO_TRAIN_ARGS`, `PGO_TRAIN_NODES`, or `PGO_TRAIN_MSEC`
-to customize training. Normal dev and OpenBench builds do not enable PGO.
-
-`tests/test_alloc.nim` checks allocation alignment. Add `EXTRA_NFLAGS=-d:noTHP`
-to its build to exercise the allocator without huge-page advice; the same flag
-can be used with the NNUE test.
-
-Just run `make test-suite`: sit back, relax, get yourself a cup of coffee and wait for it to finish (it _will_ take a long time)
-
-
-**Note**: The test suite requires Python (stdlib only) and expects stockfish to be installed and in the system's PATH. Alternatively, it
-is possible to specify the location of both Heimdall and Stockfish (run `python tests/suite.py -h` for more information)
+See [AGENTS.md](AGENTS.md#tests-and-benchmarks) for focused tests, the full test
+suite, and performance comparisons.
 
 
 ## Configuration

REUSE.toml

@@ -0,0 +1,41 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
+version = 1
+
+# These formats are consumed as data. Keep license notices here so that adding
+# comments does not change their contents or break their readers.
+[[annotations]]
+path = [
+    ".vscode/settings.json",
+    "Engines/Heimdall.json",
+    "src/heimdall/resources/magics/*.json",
+    "src/heimdall/resources/misc/bench.txt",
+    "tests/all.txt",
+    "tests/chess960.txt",
+    "tests/illegal_edge_cases.txt",
+    "tests/standard.txt",
+    "tests/standard_heavy.txt",
+]
+SPDX-FileCopyrightText = "Mattia Giambirtone & All Contributors"
+SPDX-License-Identifier = "Apache-2.0"
+
+# Generated from https://github.com/lichess-org/chess-openings.
+# Retain the upstream dataset's CC0 dedication when the index is regenerated.
+[[annotations]]
+path = "src/heimdall/resources/openings/lichess.tsv"
+SPDX-FileCopyrightText = "lichess.org contributors"
+SPDX-License-Identifier = "CC0-1.0"

TODOs.md

@@ -1,3 +1,19 @@
+<!--
+Copyright 2026 Mattia Giambirtone & All Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
 # TODO list for Heimdall releases
 
 ## 1.5 - ETA: ~1-2 month(s)

docs/AUDIT_PROGRESS.md

@@ -1,3 +1,21 @@
+<!--
+Copyright 2026 Mattia Giambirtone & All Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+Authored with assistance from AI agents.
+-->
+
 # Project audit progress
 
 Started: 2026-09-05

docs/PERFORMANCE_AUDIT_2.md

@@ -1,3 +1,21 @@
+<!--
+Copyright 2026 Mattia Giambirtone & All Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+Authored with assistance from AI agents.
+-->
+
 # Performance audit, follow-up pass
 
 Started: 2026-09-05

docs/PERFORMANCE_CARRYOVER.md

@@ -1,3 +1,21 @@
+<!--
+Copyright 2026 Mattia Giambirtone & All Contributors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+Authored with assistance from AI agents.
+-->
+
 # Search-optimization carryover experiments
 
 Started: 2026-09-06

heimdall.nimble

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 # Package
 
 # TODO: Can we do some nimscript stuff to generate this automagically?

scripts/add_tunable.py

@@ -1,4 +1,18 @@
 #!/usr/bin/env python3
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 """
 Add a tunable parameter to src/heimdall/util/tunables.nim.
 

scripts/build_openings_index.nim

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 import std/[algorithm, httpclient, os, sequtils, strutils, tables]
 
 import heimdall/[board, movegen]

scripts/check_binary_benches.py

@@ -1,4 +1,18 @@
 #!/usr/bin/env python3
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 import argparse
 import os
 import re

scripts/compare_performance.py

@@ -1,4 +1,20 @@
 #!/usr/bin/env python3
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 """Alternate paired engine workloads on one CPU and save raw samples."""
 
 import argparse

scripts/git-commit-bench

@@ -1,4 +1,18 @@
 #!/usr/bin/env bash
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 set -euo pipefail
 
 # Run bench and extract the node count

scripts/publish_gitea_release.py

@@ -1,4 +1,18 @@
 #!/usr/bin/env python3
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 """Publish release artifacts to a Gitea release."""
 
 from __future__ import annotations

scripts/uci_workload.py

@@ -1,4 +1,20 @@
 #!/usr/bin/env python3
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 """Run a selected FEN corpus with real UCI node or time limits (also PGO training)."""
 
 import argparse

src/heimdall/threats/index.nim

@@ -1,10 +1,10 @@
-# Copyright 2Pawn26 Mattia Giambirtone & All Contributors
+# Copyright 2026 Mattia Giambirtone & All Contributors
 #
-# Licensed under the Apache License, Version 2.Pawn (the "License");
+# Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 # You may obtain a copy of the License at
 #
-#    http://www.apache.org/licenses/LICENSE-2.Pawn
+#    http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,

src/heimdall/tui/analysis.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Search integration for the TUI: background search thread + live polling
 

src/heimdall/tui/app.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## TUI application entry point and main event loop
 

src/heimdall/tui/events.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Key event dispatch for the TUI.
 

src/heimdall/tui/events/board_input.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Board interaction, promotion, premove, and arrow input handling.
 

src/heimdall/tui/events/board_setup.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Board setup mode state transitions and input handling.
 

src/heimdall/tui/events/navigation.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Replay navigation and shared post-navigation refresh helpers.
 

src/heimdall/tui/graphics/board_view.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Board rendering: composites pre-rendered piece images onto the
 ## board SVG and sends the result via the kitty graphics protocol.

src/heimdall/tui/graphics/pixel.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Pixel buffer and pre-rendered chess piece/board assets
 ##

src/heimdall/tui/graphics/renderer.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Composes the full TUI layout into an illwill TerminalBuffer
 

src/heimdall/tui/input.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Text input parsing and top-level command dispatch.
 

src/heimdall/tui/input/engine_commands.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Engine, search, and position-management commands extracted from input.nim.
 

src/heimdall/tui/input/game_commands.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Play/replay/PGN command handling extracted from input.nim.
 

src/heimdall/tui/input/move_entry.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Move parsing and keyboard move-entry handling extracted from input.nim.
 

src/heimdall/tui/play.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Public play-mode API facade.
 

src/heimdall/tui/play/common.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Shared play-mode limit and clock helpers.
 

src/heimdall/tui/play/runtime.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Active play-mode game orchestration and watch/ponder runtime.
 

src/heimdall/tui/play/setup.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Play/watch setup prompts and configuration parsing.
 

src/heimdall/tui/rawinput.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Raw terminal input reader with SGR mouse support.
 ## Bypasses illwill's getKey() for input to properly handle

src/heimdall/tui/state.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Central application state for the TUI
 

src/heimdall/tui/util/clock.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Chess clock with increment support.
 

src/heimdall/tui/util/kitty.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Kitty graphics protocol for transmitting images to the terminal.
 

src/heimdall/tui/util/openings.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Bundled opening-name lookup for replay mode.
 

src/heimdall/tui/util/pgn.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## PGN (Portable Game Notation) parser.
 

src/heimdall/tui/util/premove.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Premove pseudo-legal validation and virtual-board simulation helpers.
 

src/heimdall/tui/util/san.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## SAN (Standard Algebraic Notation) parser and formatter.
 

src/heimdall/uci/shared.nim

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 import std/[strutils, terminal, strformat, options]
 
 import heimdall/[board, search, movegen]

src/heimdall/util/avx/avx512_intrin.nim

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 type
   M512i* {.importc: "__m512i", header: "immintrin.h", bycopy.} = object
 

src/heimdall/util/book_augment.nim

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 import heimdall/[eval, board, moves, search, movegen, position, transpositions]
 import heimdall/util/[wdl, limits, tunables]
 import std/[sets, math, times, strformat, atomics, random, terminal, os, strutils]

src/heimdall/util/relabel.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 import std/[atomics, math, options, os, strformat, syncio, terminal, times]
 

src/heimdall/util/viriformat.nim

@@ -11,6 +11,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+#
+# Authored with assistance from AI agents.
 
 ## Reader, writer and move decoder for viriformat 3.0.0.
 ##

tests/bench_nnue.nim

@@ -1,3 +1,19 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 ## Isolate forward inference from board updates and search. Including eval makes
 ## its private accumulator layout available to this diagnostic program only.
 ## Build with make dev MAIN=tests/bench_nnue.nim EXE_BASE=bin/bench-nnue

tests/bench_setup.nim

@@ -1,3 +1,19 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 ## Measure repeated position setup, including worker NNUE state preparation.
 ## Build with make dev MAIN=tests/bench_setup.nim EXE_BASE=bin/bench-setup
 ## and an absolute EVALFILE path. Arguments: threads (default 8), repetitions.

tests/compare_positions.py

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 import builtins
 import re
 import sys

tests/suite.py

@@ -1,3 +1,17 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 import sys
 import timeit
 from pathlib import Path

tests/test_alloc.nim

@@ -1,3 +1,19 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 ## Check the alignment contract with and without huge-page advice.
 ## Build with make dev MAIN=tests/test_alloc.nim EXE_BASE=bin/test-alloc.
 import heimdall/util/memory/thp/alloc

tests/test_genfens.py

@@ -1,3 +1,19 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 """OpenBench genfens regressions. Build first with make dev."""
 
 import os

tests/test_limits.nim

@@ -1,3 +1,19 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 ## Deterministic limiter checks, including depth/MultiPV and mixed hard limits.
 ## Build via make dev MAIN=tests/test_limits.nim IS_TEST=1 with absolute EVALFILE.
 import std/[atomics, monotimes, times]

tests/test_movegen.nim

@@ -1,3 +1,19 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 ## Focused move-generation invariants for performance-sensitive specializations.
 ## Build with:
 ## make dev MAIN=tests/test_movegen.nim IS_TEST=1 EXE_BASE=bin/test-movegen \

tests/test_nnue.nim

@@ -1,3 +1,19 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 ## Exercise incremental and delayed NNUE updates against a full refresh.
 ## Build using make dev MAIN=tests/test_nnue.nim EXE_BASE=bin/test-nnue
 ## with EVALFILE set to the absolute path of the desired network.

tests/test_performance_tools.py

@@ -1,3 +1,19 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 """Regression checks for the UCI performance/PGO workload driver."""
 import importlib.util
 import tempfile

tests/test_pieces.nim

@@ -1,3 +1,19 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 ## Packed piece representation and public API checks.
 ## Build with make dev MAIN=tests/test_pieces.nim IS_TEST=1 EXE_BASE=bin/test-pieces
 ## and EVALFILE set to the absolute network path.

tests/test_test_tools.py

@@ -1,3 +1,19 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 """Regression tests for the perft comparison tools; no engines required."""
 
 import contextlib

tests/test_threat_index.nim

@@ -1,3 +1,19 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 ## Threat geometry, indexing, perspective masks, bounds and collision regressions.
 ## Build with make dev MAIN=tests/test_threat_index.nim IS_TEST=1
 ## EXE_BASE=bin/test-threat-index and an absolute EVALFILE path.

tests/test_threats.nim

@@ -1,3 +1,19 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 ## Runtime threat attacks and full collection against independent board geometry.
 ## Build with make dev MAIN=tests/test_threats.nim IS_TEST=1
 ## EXE_BASE=bin/test-threats and an absolute EVALFILE path.
@@ -6,7 +22,11 @@ import heimdall/[board, movegen, nnue, pieces, position]
 import heimdall/threats/index
 
 
-var attackChecks, collectionChecks: int
+const
+    STARTPOS_FEN = "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1"
+    KIWIPETE_FEN = "r3k2r/p1ppqpb1/bn2pnp1/3PN3/1p2P3/2N2Q1p/PPPBBPPP/R3K2R w KQkq - 0 1"
+
+var attackChecks, collectionChecks, knownIndexChecks: int
 
 
 proc geometricAttack(piece: Piece, origin, target: Square, occupancy: Bitboard): bool =
@@ -117,12 +137,54 @@ for mirrored in [false, true]:
 verifyCollection(fromFEN("4k3/8/8/8/8/8/8/4K3 w - - 0 1"), 0)
 verifyCollection(fromFEN("4k3/8/8/8/8/r7/K7/R7 w - - 0 1"), 0)
 
+
+proc verifyKnownIndices(fen: string, whiteExpected, blackExpected: openArray[uint16]) =
+    let position = fromFEN(fen)
+    for perspective in White..Black:
+        var output: array[1024, uint16]
+        let count = collectRefreshThreats(output, position, perspective).int
+        var actual: seq[uint16]
+        for i in 0..<count:
+            actual.add output[i]
+        actual.sort()
+        let expected = if perspective == White: @whiteExpected else: @blackExpected
+        doAssert actual == expected,
+            &"known index mismatch for {perspective}: {fen}\nexpected: {expected}\nactual: {actual}"
+        inc knownIndexChecks
+
+
+# Fixed expected indices from Viridithas, independent of Heimdall's indexer.
+# https://github.com/cosmobobak/viridithas/blob/89a83b692e175eddaeeb1a626d314927e614d48d/src/nnue/network/threat_updates.rs#L765
+# Both engines normalize features to a1=0, so board-coordinate differences
+# must not change these row numbers. The starting position is symmetric.
+const
+    startposIndices = [
+        506'u16, 525, 3878, 3879, 3899, 3900, 8351, 8449, 9240, 9344, 15603, 15604,
+        15605, 18512, 32570, 32589, 36699, 36700, 36720, 36721, 42790, 42888, 43687,
+        43791, 54247, 54248, 54249, 57166
+    ]
+    kiwipeteWhiteIndices = [
+        34'u16, 95, 605, 606, 608, 1276, 2034, 2374, 2376, 2377, 4517, 8351, 8449,
+        15907, 15908, 15919, 17370, 18821, 23190, 24659, 30086, 30134, 30195, 30397,
+        30398, 30401, 30488, 30491, 30807, 30809, 30840, 32491, 32521, 33531, 35486,
+        37185, 38306, 42786, 42888, 54045, 54050, 54054, 54055, 55505
+    ]
+    kiwipeteBlackIndices = [
+        3'u16, 4, 7, 94, 97, 389, 581, 612, 1619, 2263, 2265, 2293, 4490, 5607,
+        8355, 8449, 15752, 15753, 15758, 15765, 17213, 30107, 30143, 30372, 30489,
+        30710, 30711, 30712, 32510, 32512, 32515, 33186, 33740, 35517, 37212, 42790,
+        42888, 46560, 48008, 53839, 53847, 53848, 55300, 56761
+    ]
+
+verifyKnownIndices(STARTPOS_FEN, startposIndices, startposIndices)
+verifyKnownIndices(KIWIPETE_FEN, kiwipeteWhiteIndices, kiwipeteBlackIndices)
+
 var
     rng = initRand(90210)
     moveFlags: set[MoveFlag]
 for fen in [
-    "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1",
-    "r3k2r/p1ppqpb1/bn2pnp1/3PN3/1p2P3/2N2Q1p/PPPBBPPP/R3K2R w KQkq - 0 1",
+    STARTPOS_FEN,
+    KIWIPETE_FEN,
     "r3k2r/8/8/8/8/8/8/R3K2R w KQkq - 0 1",
     "4k3/8/8/3pP3/8/8/8/4K3 w - d6 0 1",
     "4k3/8/8/8/3Pp3/8/8/4K3 b - d3 0 1",
@@ -161,4 +223,5 @@ for flag in [Normal, DoublePush, Capture, EnPassant, ShortCastling, LongCastling
              CapturePromotionQueen, CapturePromotionRook, CapturePromotionBishop, CapturePromotionKnight]:
     doAssert flag in moveFlags, &"missing move coverage: {flag}"
 
-echo &"Threat collection: {attackChecks} attack-square checks; {collectionChecks} full collector comparisons"
+echo &"Threat collection: {attackChecks} attack-square checks; {collectionChecks} full collector comparisons; " &
+     &"{knownIndexChecks} known index comparisons"

tests/test_uci.py

@@ -1,3 +1,19 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 """UCI regressions. Build first with make dev; override the binary with HEIMDALL."""
 
 import os

tests/test_viriformat.nim

@@ -1,3 +1,19 @@
+# Copyright 2026 Mattia Giambirtone & All Contributors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Authored with assistance from AI agents.
+
 import std/[os, syncio, tempfiles, unittest]
 
 import heimdall/[movegen, moves, pieces, position]