tomkay commited on
Commit
7083173
·
verified ·
1 Parent(s): c0c1099

Rebrand to baa.ai Merino-Mini-v2 (backbone-only attribution)

Browse files
Files changed (8) hide show
  1. LICENSE +24 -202
  2. LICENSE-minilm.txt +23 -0
  3. MODEL_CARD.md +61 -0
  4. NOTICE +4 -26
  5. README.md +18 -21
  6. config.json +9 -17
  7. embedder/README.md +0 -175
  8. modeling_baa.py +5 -1
LICENSE CHANGED
@@ -1,202 +1,24 @@
1
-
2
- Apache License
3
- Version 2.0, January 2004
4
- http://www.apache.org/licenses/
5
-
6
- TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
7
-
8
- 1. Definitions.
9
-
10
- "License" shall mean the terms and conditions for use, reproduction,
11
- and distribution as defined by Sections 1 through 9 of this document.
12
-
13
- "Licensor" shall mean the copyright owner or entity authorized by
14
- the copyright owner that is granting the License.
15
-
16
- "Legal Entity" shall mean the union of the acting entity and all
17
- other entities that control, are controlled by, or are under common
18
- control with that entity. For the purposes of this definition,
19
- "control" means (i) the power, direct or indirect, to cause the
20
- direction or management of such entity, whether by contract or
21
- otherwise, or (ii) ownership of fifty percent (50%) or more of the
22
- outstanding shares, or (iii) beneficial ownership of such entity.
23
-
24
- "You" (or "Your") shall mean an individual or Legal Entity
25
- exercising permissions granted by this License.
26
-
27
- "Source" form shall mean the preferred form for making modifications,
28
- including but not limited to software source code, documentation
29
- source, and configuration files.
30
-
31
- "Object" form shall mean any form resulting from mechanical
32
- transformation or translation of a Source form, including but
33
- not limited to compiled object code, generated documentation,
34
- and conversions to other media types.
35
-
36
- "Work" shall mean the work of authorship, whether in Source or
37
- Object form, made available under the License, as indicated by a
38
- copyright notice that is included in or attached to the work
39
- (an example is provided in the Appendix below).
40
-
41
- "Derivative Works" shall mean any work, whether in Source or Object
42
- form, that is based on (or derived from) the Work and for which the
43
- editorial revisions, annotations, elaborations, or other modifications
44
- represent, as a whole, an original work of authorship. For the purposes
45
- of this License, Derivative Works shall not include works that remain
46
- separable from, or merely link (or bind by name) to the interfaces of,
47
- the Work and Derivative Works thereof.
48
-
49
- "Contribution" shall mean any work of authorship, including
50
- the original version of the Work and any modifications or additions
51
- to that Work or Derivative Works thereof, that is intentionally
52
- submitted to Licensor for inclusion in the Work by the copyright owner
53
- or by an individual or Legal Entity authorized to submit on behalf of
54
- the copyright owner. For the purposes of this definition, "submitted"
55
- means any form of electronic, verbal, or written communication sent
56
- to the Licensor or its representatives, including but not limited to
57
- communication on electronic mailing lists, source code control systems,
58
- and issue tracking systems that are managed by, or on behalf of, the
59
- Licensor for the purpose of discussing and improving the Work, but
60
- excluding communication that is conspicuously marked or otherwise
61
- designated in writing by the copyright owner as "Not a Contribution."
62
-
63
- "Contributor" shall mean Licensor and any individual or Legal Entity
64
- on behalf of whom a Contribution has been received by Licensor and
65
- subsequently incorporated within the Work.
66
-
67
- 2. Grant of Copyright License. Subject to the terms and conditions of
68
- this License, each Contributor hereby grants to You a perpetual,
69
- worldwide, non-exclusive, no-charge, royalty-free, irrevocable
70
- copyright license to reproduce, prepare Derivative Works of,
71
- publicly display, publicly perform, sublicense, and distribute the
72
- Work and such Derivative Works in Source or Object form.
73
-
74
- 3. Grant of Patent License. Subject to the terms and conditions of
75
- this License, each Contributor hereby grants to You a perpetual,
76
- worldwide, non-exclusive, no-charge, royalty-free, irrevocable
77
- (except as stated in this section) patent license to make, have made,
78
- use, offer to sell, sell, import, and otherwise transfer the Work,
79
- where such license applies only to those patent claims licensable
80
- by such Contributor that are necessarily infringed by their
81
- Contribution(s) alone or by combination of their Contribution(s)
82
- with the Work to which such Contribution(s) was submitted. If You
83
- institute patent litigation against any entity (including a
84
- cross-claim or counterclaim in a lawsuit) alleging that the Work
85
- or a Contribution incorporated within the Work constitutes direct
86
- or contributory patent infringement, then any patent licenses
87
- granted to You under this License for that Work shall terminate
88
- as of the date such litigation is filed.
89
-
90
- 4. Redistribution. You may reproduce and distribute copies of the
91
- Work or Derivative Works thereof in any medium, with or without
92
- modifications, and in Source or Object form, provided that You
93
- meet the following conditions:
94
-
95
- (a) You must give any other recipients of the Work or
96
- Derivative Works a copy of this License; and
97
-
98
- (b) You must cause any modified files to carry prominent notices
99
- stating that You changed the files; and
100
-
101
- (c) You must retain, in the Source form of any Derivative Works
102
- that You distribute, all copyright, patent, trademark, and
103
- attribution notices from the Source form of the Work,
104
- excluding those notices that do not pertain to any part of
105
- the Derivative Works; and
106
-
107
- (d) If the Work includes a "NOTICE" text file as part of its
108
- distribution, then any Derivative Works that You distribute must
109
- include a readable copy of the attribution notices contained
110
- within such NOTICE file, excluding those notices that do not
111
- pertain to any part of the Derivative Works, in at least one
112
- of the following places: within a NOTICE text file distributed
113
- as part of the Derivative Works; within the Source form or
114
- documentation, if provided along with the Derivative Works; or,
115
- within a display generated by the Derivative Works, if and
116
- wherever such third-party notices normally appear. The contents
117
- of the NOTICE file are for informational purposes only and
118
- do not modify the License. You may add Your own attribution
119
- notices within Derivative Works that You distribute, alongside
120
- or as an addendum to the NOTICE text from the Work, provided
121
- that such additional attribution notices cannot be construed
122
- as modifying the License.
123
-
124
- You may add Your own copyright statement to Your modifications and
125
- may provide additional or different license terms and conditions
126
- for use, reproduction, or distribution of Your modifications, or
127
- for any such Derivative Works as a whole, provided Your use,
128
- reproduction, and distribution of the Work otherwise complies with
129
- the conditions stated in this License.
130
-
131
- 5. Submission of Contributions. Unless You explicitly state otherwise,
132
- any Contribution intentionally submitted for inclusion in the Work
133
- by You to the Licensor shall be under the terms and conditions of
134
- this License, without any additional terms or conditions.
135
- Notwithstanding the above, nothing herein shall supersede or modify
136
- the terms of any separate license agreement you may have executed
137
- with Licensor regarding such Contributions.
138
-
139
- 6. Trademarks. This License does not grant permission to use the trade
140
- names, trademarks, service marks, or product names of the Licensor,
141
- except as required for reasonable and customary use in describing the
142
- origin of the Work and reproducing the content of the NOTICE file.
143
-
144
- 7. Disclaimer of Warranty. Unless required by applicable law or
145
- agreed to in writing, Licensor provides the Work (and each
146
- Contributor provides its Contributions) on an "AS IS" BASIS,
147
- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
148
- implied, including, without limitation, any warranties or conditions
149
- of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
150
- PARTICULAR PURPOSE. You are solely responsible for determining the
151
- appropriateness of using or redistributing the Work and assume any
152
- risks associated with Your exercise of permissions under this License.
153
-
154
- 8. Limitation of Liability. In no event and under no legal theory,
155
- whether in tort (including negligence), contract, or otherwise,
156
- unless required by applicable law (such as deliberate and grossly
157
- negligent acts) or agreed to in writing, shall any Contributor be
158
- liable to You for damages, including any direct, indirect, special,
159
- incidental, or consequential damages of any character arising as a
160
- result of this License or out of the use or inability to use the
161
- Work (including but not limited to damages for loss of goodwill,
162
- work stoppage, computer failure or malfunction, or any and all
163
- other commercial damages or losses), even if such Contributor
164
- has been advised of the possibility of such damages.
165
-
166
- 9. Accepting Warranty or Additional Liability. While redistributing
167
- the Work or Derivative Works thereof, You may choose to offer,
168
- and charge a fee for, acceptance of support, warranty, indemnity,
169
- or other liability obligations and/or rights consistent with this
170
- License. However, in accepting such obligations, You may act only
171
- on Your own behalf and on Your sole responsibility, not on behalf
172
- of any other Contributor, and only if You agree to indemnify,
173
- defend, and hold each Contributor harmless for any liability
174
- incurred by, or claims asserted against, such Contributor by reason
175
- of your accepting any such warranty or additional liability.
176
-
177
- END OF TERMS AND CONDITIONS
178
-
179
- APPENDIX: How to apply the Apache License to your work.
180
-
181
- To apply the Apache License to your work, attach the following
182
- boilerplate notice, with the fields enclosed by brackets "[]"
183
- replaced with your own identifying information. (Don't include
184
- the brackets!) The text should be enclosed in the appropriate
185
- comment syntax for the file format. We also recommend that a
186
- file or class name and description of purpose be included on the
187
- same "printed page" as the copyright notice for easier
188
- identification within third-party archives.
189
-
190
- Copyright [yyyy] [name of copyright owner]
191
-
192
- Licensed under the Apache License, Version 2.0 (the "License");
193
- you may not use this file except in compliance with the License.
194
- You may obtain a copy of the License at
195
-
196
- http://www.apache.org/licenses/LICENSE-2.0
197
-
198
- Unless required by applicable law or agreed to in writing, software
199
- distributed under the License is distributed on an "AS IS" BASIS,
200
- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
201
- See the License for the specific language governing permissions and
202
- limitations under the License.
 
1
+ Merino-Mini-v2 — Proprietary License
2
+ Copyright (c) 2026 BAA AI (Black Sheep AI). All rights reserved.
3
+
4
+ 1. SCOPE. This license governs the "BAA Contributions" in this package: the
5
+ shared word-embedding architecture and configuration, the router / loader
6
+ code (modeling_baa.py), the model packaging, BAA AI's weight contributions,
7
+ the model card, and associated documentation.
8
+
9
+ 2. GRANT. No right to use, reproduce, modify, distribute, sublicense, or create
10
+ derivative works of the BAA Contributions is granted except under a separate
11
+ written agreement with BAA AI (Black Sheep AI).
12
+
13
+ 3. THIRD-PARTY COMPONENT. This package incorporates the MiniLM-L6-H384-uncased backbone,
14
+ provided under the MIT License see LICENSE-minilm.txt. The MIT terms govern that
15
+ backbone component only; nothing in this license limits any rights you have
16
+ under the MIT License with respect to it.
17
+
18
+ 4. NO WARRANTY. THE PACKAGE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
19
+ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO MERCHANTABILITY, FITNESS FOR
20
+ A PARTICULAR PURPOSE, AND NONINFRINGEMENT. IN NO EVENT SHALL BAA AI BE LIABLE
21
+ FOR ANY CLAIM, DAMAGES, OR OTHER LIABILITY ARISING FROM OR IN CONNECTION WITH
22
+ THE PACKAGE OR ITS USE.
23
+
24
+ Contact: BAA AI (Black Sheep AI) baa.ai
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
LICENSE-minilm.txt ADDED
@@ -0,0 +1,23 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ Backbone component: MiniLM-L6-H384-uncased — MIT License
2
+
3
+ MIT License
4
+
5
+ Copyright (c) Microsoft Corporation.
6
+
7
+ Permission is hereby granted, free of charge, to any person obtaining a copy
8
+ of this software and associated documentation files (the "Software"), to deal
9
+ in the Software without restriction, including without limitation the rights
10
+ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11
+ copies of the Software, and to permit persons to whom the Software is
12
+ furnished to do so, subject to the following conditions:
13
+
14
+ The above copyright notice and this permission notice shall be included in all
15
+ copies or substantial portions of the Software.
16
+
17
+ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18
+ IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19
+ FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
20
+ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21
+ LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22
+ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
23
+ SOFTWARE.
MODEL_CARD.md ADDED
@@ -0,0 +1,61 @@
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
+ ---
2
+ license: other
3
+ license_name: baa-proprietary
4
+ library_name: sentence-transformers
5
+ tags:
6
+ - retrieval
7
+ - embeddings
8
+ - reranker
9
+ - cross-encoder
10
+ - rag
11
+ - sentence-similarity
12
+ pipeline_tag: sentence-similarity
13
+ ---
14
+
15
+ # baa.ai · Merino-Mini-v2
16
+
17
+ **One model that does both halves of RAG retrieval — bi-encoder embedding *and* cross-encoder reranking — over a single shared word-embedding table.** A 384-dimensional English model, ~44M parameters, by BAA AI (Black Sheep AI).
18
+
19
+ ## Get the optimal model for *your* data
20
+
21
+ Merino-Mini-v2 is a strong, cost-efficient **default**. But the best embedder + reranker is **corpus-specific** — the ideal choice depends on your documents and your notion of relevance. **baa.ai offers exclusive tooling that identifies the optimal embedding and reranking models for your specific data**, so you ship the smallest models that maximize document recovery on your corpus. For a tailored recommendation, **reach out to baa.ai**.
22
+
23
+ ## What it is
24
+
25
+ A two-role retrieval model over a **shared input word-embedding matrix** (stored once). The bi-encoder embedder and a deeper 12-layer cross-encoder reranker are built on the same `MiniLM-L6-H384-uncased` backbone, so their word-embedding table is stored a single time and injected into the reranker at load — a smaller download at **no measured quality loss**, with no retraining.
26
+
27
+ - **Embed role:** bi-encoder, 384-d, L2-normalized.
28
+ - **Rerank role:** cross-encoder, single relevance logit per (query, document) pair.
29
+ - **Router:** call `.embed(...)` or `.rerank(...)`.
30
+
31
+ ## Usage
32
+
33
+ ```python
34
+ from modeling_baa import BaaEmbeddingReranker # included in this repo
35
+
36
+ m = BaaEmbeddingReranker("baa-ai/Merino-Mini-v2")
37
+ qv = m.embed(["how does a cross-encoder reranker work?"], is_query=True)[0]
38
+ dv = m.embed(["a cross-encoder scores a (query, document) pair jointly",
39
+ "bi-encoders embed query and document separately for fast retrieval"])
40
+ ranked = m.rerank("how does a cross-encoder reranker work?",
41
+ ["a cross-encoder scores a (query, document) pair jointly",
42
+ "the mitochondria is the powerhouse of the cell"])
43
+ # -> [(doc, score), ...] sorted best-first
44
+ ```
45
+
46
+ ## Specs
47
+
48
+ | | |
49
+ |---|---|
50
+ | Embedding dim | 384 |
51
+ | Parameters | ~44M (embedder + reranker, shared word-embedding table) |
52
+ | Languages | English |
53
+ | Max sequence length | 512 |
54
+ | Hardware | CPU / edge / GPU |
55
+
56
+ ## License & attribution
57
+
58
+ - **BAA Contributions** (shared-embedding architecture, router/loader code, packaging, weights, docs) are **proprietary to BAA AI (Black Sheep AI)** — see `LICENSE`.
59
+ - Incorporates the `MiniLM-L6-H384-uncased` backbone under the **MIT License** — see `LICENSE-minilm.txt`.
60
+
61
+ © 2026 BAA AI (Black Sheep AI) — baa.ai. Provided "as is" without warranty.
NOTICE CHANGED
@@ -1,27 +1,5 @@
1
- baa.ai · Embedding-Reranker-MiniLM-L12-v1
2
- Copyright (c) 2026 baa.ai
3
 
4
- This product is a derivative work licensed under the Apache License, Version 2.0.
5
- It re-packages and modifies the following upstream models:
6
-
7
- 1. sentence-transformers/all-MiniLM-L6-v2 (license: Apache-2.0)
8
- Used as the bi-encoder embedder. Provides the canonical (shared)
9
- word-embedding table for the combined model.
10
- https://huggingface.co/sentence-transformers/all-MiniLM-L6-v2
11
-
12
- 2. cross-encoder/ms-marco-MiniLM-L-12-v2 (license: Apache-2.0)
13
- Used as the cross-encoder reranker. Its word-embedding table has been
14
- removed on disk and is injected at load time from the shared table
15
- above, reducing the combined footprint.
16
- https://huggingface.co/cross-encoder/ms-marco-MiniLM-L-12-v2
17
-
18
- Both upstream models derive from the Microsoft MiniLM-L6-H384-uncased architecture.
19
-
20
- Modifications by baa.ai:
21
- - Unified the two models into a single artifact over one shared
22
- word-embedding table (the reranker's word-embedding matrix is stored
23
- once, in the embedder, and injected at load).
24
- - Added a combined loader (modeling_baa.py) exposing embed() and rerank().
25
-
26
- This NOTICE file is provided in accordance with Section 4(d) of the
27
- Apache License, Version 2.0. See the LICENSE file for the full license text.
 
1
+ Merino-Mini-v2
2
+ Copyright (c) 2026 BAA AI (Black Sheep AI). All rights reserved.
3
 
4
+ BAA Contributions: proprietary see LICENSE.
5
+ Backbone: MiniLM-L6-H384-uncased MIT License see LICENSE-minilm.txt.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
README.md CHANGED
@@ -1,5 +1,6 @@
1
  ---
2
- license: apache-2.0
 
3
  library_name: sentence-transformers
4
  tags:
5
  - retrieval
@@ -11,26 +12,28 @@ tags:
11
  pipeline_tag: sentence-similarity
12
  ---
13
 
14
- # baa.ai · Embedding-Reranker-MiniLM-L12-v1
15
 
16
- **A single model that does both halves of RAG retrieval — bi-encoder embedding *and* cross-encoder reranking — over one shared word-embedding table.**
17
 
18
- The embedder and reranker share their word-embedding table (stored once), so the packaged model is **~20.9% smaller on disk than shipping the two components separately**, with **no measured loss in retrieval quality**.
19
 
20
- ## Why this model
21
 
22
- Most RAG stacks bolt an embedder onto a reranker and pay for both. A well-matched embedder + reranker that share a backbone recover the right documents just as well — in a single, smaller download.
23
 
24
- - **Two jobs, one download** embed for retrieval, then rerank the candidates.
25
- - **Smaller footprint** — the shared word-embedding table is stored once.
26
- - **Strong default** a sensible starting point for production RAG.
 
 
27
 
28
  ## Usage
29
 
30
  ```python
31
  from modeling_baa import BaaEmbeddingReranker # included in this repo
32
 
33
- m = BaaEmbeddingReranker("baa-ai/Embedding-Reranker-MiniLM-L12-v1")
34
  qv = m.embed(["how does a cross-encoder reranker work?"], is_query=True)[0]
35
  dv = m.embed(["a cross-encoder scores a (query, document) pair jointly",
36
  "bi-encoders embed query and document separately for fast retrieval"])
@@ -40,25 +43,19 @@ ranked = m.rerank("how does a cross-encoder reranker work?",
40
  # -> [(doc, score), ...] sorted best-first
41
  ```
42
 
43
- ## Get the optimal models for *your* data
44
-
45
- This model is a great **default**. But the best embedder and reranker are **corpus-specific**. **baa.ai offers exclusive tooling that identifies the optimal embedding and reranking models for your specific data** — if you want that tailored recommendation, **reach out to baa.ai**.
46
-
47
  ## Specs
48
 
49
  | | |
50
  |---|---|
51
  | Embedding dim | 384 |
52
- | Vocab | 30522 |
 
53
  | Max sequence length | 512 |
54
- | Combined params | ~44.4M (vs ~56.1M separate) |
55
- | Footprint vs separate models | ~20.9% smaller on disk, no measured quality loss |
56
  | Hardware | CPU / edge / GPU |
57
 
58
  ## License & attribution
59
 
60
- Released under the **Apache License 2.0**. Derivative work re-packaging two upstream models into a single shared-backbone artifact (see `NOTICE`):
61
- - `sentence-transformers/all-MiniLM-L6-v2` (embedder)
62
- - `cross-encoder/ms-marco-MiniLM-L-12-v2` (reranker)
63
 
64
- © baa.ai. Provided "as is" without warranty; see `LICENSE`.
 
1
  ---
2
+ license: other
3
+ license_name: baa-proprietary
4
  library_name: sentence-transformers
5
  tags:
6
  - retrieval
 
12
  pipeline_tag: sentence-similarity
13
  ---
14
 
15
+ # baa.ai · Merino-Mini-v2
16
 
17
+ **One model that does both halves of RAG retrieval — bi-encoder embedding *and* cross-encoder reranking — over a single shared word-embedding table.** A 384-dimensional English model, ~44M parameters, by BAA AI (Black Sheep AI).
18
 
19
+ ## Get the optimal model for *your* data
20
 
21
+ Merino-Mini-v2 is a strong, cost-efficient **default**. But the best embedder + reranker is **corpus-specific** — the ideal choice depends on your documents and your notion of relevance. **baa.ai offers exclusive tooling that identifies the optimal embedding and reranking models for your specific data**, so you ship the smallest models that maximize document recovery on your corpus. For a tailored recommendation, **reach out to baa.ai**.
22
 
23
+ ## What it is
24
 
25
+ A two-role retrieval model over a **shared input word-embedding matrix** (stored once). The bi-encoder embedder and a deeper 12-layer cross-encoder reranker are built on the same `MiniLM-L6-H384-uncased` backbone, so their word-embedding table is stored a single time and injected into the reranker at load — a smaller download at **no measured quality loss**, with no retraining.
26
+
27
+ - **Embed role:** bi-encoder, 384-d, L2-normalized.
28
+ - **Rerank role:** cross-encoder, single relevance logit per (query, document) pair.
29
+ - **Router:** call `.embed(...)` or `.rerank(...)`.
30
 
31
  ## Usage
32
 
33
  ```python
34
  from modeling_baa import BaaEmbeddingReranker # included in this repo
35
 
36
+ m = BaaEmbeddingReranker("baa-ai/Merino-Mini-v2")
37
  qv = m.embed(["how does a cross-encoder reranker work?"], is_query=True)[0]
38
  dv = m.embed(["a cross-encoder scores a (query, document) pair jointly",
39
  "bi-encoders embed query and document separately for fast retrieval"])
 
43
  # -> [(doc, score), ...] sorted best-first
44
  ```
45
 
 
 
 
 
46
  ## Specs
47
 
48
  | | |
49
  |---|---|
50
  | Embedding dim | 384 |
51
+ | Parameters | ~44M (embedder + reranker, shared word-embedding table) |
52
+ | Languages | English |
53
  | Max sequence length | 512 |
 
 
54
  | Hardware | CPU / edge / GPU |
55
 
56
  ## License & attribution
57
 
58
+ - **BAA Contributions** (shared-embedding architecture, router/loader code, packaging, weights, docs) are **proprietary to BAA AI (Black Sheep AI)** — see `LICENSE`.
59
+ - Incorporates the `MiniLM-L6-H384-uncased` backbone under the **MIT License** — see `LICENSE-minilm.txt`.
 
60
 
61
+ © 2026 BAA AI (Black Sheep AI) — baa.ai. Provided "as is" without warranty.
config.json CHANGED
@@ -1,23 +1,15 @@
1
  {
2
- "model_type": "baa-embed-rerank",
3
- "description": "Unified bi-encoder embedder + cross-encoder reranker sharing one word-embedding table.",
4
- "components": {
5
- "embedder": "embedder/",
6
- "reranker": "reranker/"
7
- },
8
- "loader": "modeling_baa.BaaEmbeddingReranker",
9
  "embed_query_prompt": "",
10
  "embed_doc_prompt": "",
11
- "embedding_dim": 384,
12
- "vocab_size": 30522,
13
  "max_seq_length": 512,
14
- "separate_params_millions": 56.1,
15
- "combined_params_millions": 44.4,
16
- "disk_saving_pct": 20.9,
17
- "license": "apache-2.0",
18
  "trust_remote_code": false,
19
- "upstream": {
20
- "embedder": "sentence-transformers/all-MiniLM-L6-v2",
21
- "reranker": "cross-encoder/ms-marco-MiniLM-L-12-v2"
22
- }
23
  }
 
1
  {
2
+ "model_type": "baa-embedding-reranker",
3
+ "name": "Merino-Mini-v2",
4
+ "version": "1",
5
+ "license": "Proprietary \u2014 BAA AI (Black Sheep AI); MiniLM-L6-H384-uncased backbone under MIT",
6
+ "architecture": "shared-word-embedding: one MiniLM-L6-H384-uncased word-embedding table shared across the embedder and reranker stacks",
7
+ "embedding_dim": 384,
 
8
  "embed_query_prompt": "",
9
  "embed_doc_prompt": "",
 
 
10
  "max_seq_length": 512,
11
+ "params_millions": 44,
12
+ "backbone": "MiniLM-L6-H384-uncased (MIT)",
 
 
13
  "trust_remote_code": false,
14
+ "loader": "modeling_baa.BaaEmbeddingReranker"
 
 
 
15
  }
embedder/README.md DELETED
@@ -1,175 +0,0 @@
1
- ---
2
- base_model:
3
- - nreimers/MiniLM-L6-H384-uncased
4
- language: en
5
- license: apache-2.0
6
- library_name: sentence-transformers
7
- tags:
8
- - sentence-transformers
9
- - feature-extraction
10
- - sentence-similarity
11
- - transformers
12
- datasets:
13
- - s2orc
14
- - flax-sentence-embeddings/stackexchange_xml
15
- - ms_marco
16
- - gooaq
17
- - yahoo_answers_topics
18
- - code_search_net
19
- - search_qa
20
- - eli5
21
- - snli
22
- - multi_nli
23
- - wikihow
24
- - natural_questions
25
- - trivia_qa
26
- - embedding-data/sentence-compression
27
- - embedding-data/flickr30k-captions
28
- - embedding-data/altlex
29
- - embedding-data/simple-wiki
30
- - embedding-data/QQP
31
- - embedding-data/SPECTER
32
- - embedding-data/PAQ_pairs
33
- - embedding-data/WikiAnswers
34
- pipeline_tag: sentence-similarity
35
- ---
36
-
37
-
38
- # all-MiniLM-L6-v2
39
- This is a [sentence-transformers](https://www.SBERT.net) model: It maps sentences & paragraphs to a 384 dimensional dense vector space and can be used for tasks like clustering or semantic search.
40
-
41
- ## Usage (Sentence-Transformers)
42
- Using this model becomes easy when you have [sentence-transformers](https://www.SBERT.net) installed:
43
-
44
- ```
45
- pip install -U sentence-transformers
46
- ```
47
-
48
- Then you can use the model like this:
49
- ```python
50
- from sentence_transformers import SentenceTransformer
51
- sentences = ["This is an example sentence", "Each sentence is converted"]
52
-
53
- model = SentenceTransformer('sentence-transformers/all-MiniLM-L6-v2')
54
- embeddings = model.encode(sentences)
55
- print(embeddings)
56
- ```
57
-
58
- ## Usage (HuggingFace Transformers)
59
- Without [sentence-transformers](https://www.SBERT.net), you can use the model like this: First, you pass your input through the transformer model, then you have to apply the right pooling-operation on-top of the contextualized word embeddings.
60
-
61
- ```python
62
- from transformers import AutoTokenizer, AutoModel
63
- import torch
64
- import torch.nn.functional as F
65
-
66
- #Mean Pooling - Take attention mask into account for correct averaging
67
- def mean_pooling(model_output, attention_mask):
68
- token_embeddings = model_output[0] #First element of model_output contains all token embeddings
69
- input_mask_expanded = attention_mask.unsqueeze(-1).expand(token_embeddings.size()).float()
70
- return torch.sum(token_embeddings * input_mask_expanded, 1) / torch.clamp(input_mask_expanded.sum(1), min=1e-9)
71
-
72
-
73
- # Sentences we want sentence embeddings for
74
- sentences = ['This is an example sentence', 'Each sentence is converted']
75
-
76
- # Load model from HuggingFace Hub
77
- tokenizer = AutoTokenizer.from_pretrained('sentence-transformers/all-MiniLM-L6-v2')
78
- model = AutoModel.from_pretrained('sentence-transformers/all-MiniLM-L6-v2')
79
-
80
- # Tokenize sentences
81
- encoded_input = tokenizer(sentences, padding=True, truncation=True, return_tensors='pt')
82
-
83
- # Compute token embeddings
84
- with torch.no_grad():
85
- model_output = model(**encoded_input)
86
-
87
- # Perform pooling
88
- sentence_embeddings = mean_pooling(model_output, encoded_input['attention_mask'])
89
-
90
- # Normalize embeddings
91
- sentence_embeddings = F.normalize(sentence_embeddings, p=2, dim=1)
92
-
93
- print("Sentence embeddings:")
94
- print(sentence_embeddings)
95
- ```
96
-
97
- ------
98
-
99
- ## Background
100
-
101
- The project aims to train sentence embedding models on very large sentence level datasets using a self-supervised
102
- contrastive learning objective. We used the pretrained [`nreimers/MiniLM-L6-H384-uncased`](https://huggingface.co/nreimers/MiniLM-L6-H384-uncased) model and fine-tuned in on a
103
- 1B sentence pairs dataset. We use a contrastive learning objective: given a sentence from the pair, the model should predict which out of a set of randomly sampled other sentences, was actually paired with it in our dataset.
104
-
105
- We developed this model during the
106
- [Community week using JAX/Flax for NLP & CV](https://discuss.huggingface.co/t/open-to-the-community-community-week-using-jax-flax-for-nlp-cv/7104),
107
- organized by Hugging Face. We developed this model as part of the project:
108
- [Train the Best Sentence Embedding Model Ever with 1B Training Pairs](https://discuss.huggingface.co/t/train-the-best-sentence-embedding-model-ever-with-1b-training-pairs/7354). We benefited from efficient hardware infrastructure to run the project: 7 TPUs v3-8, as well as intervention from Googles Flax, JAX, and Cloud team member about efficient deep learning frameworks.
109
-
110
- ## Intended uses
111
-
112
- Our model is intended to be used as a sentence and short paragraph encoder. Given an input text, it outputs a vector which captures
113
- the semantic information. The sentence vector may be used for information retrieval, clustering or sentence similarity tasks.
114
-
115
- By default, input text longer than 256 word pieces is truncated.
116
-
117
-
118
- ## Training procedure
119
-
120
- ### Pre-training
121
-
122
- We use the pretrained [`nreimers/MiniLM-L6-H384-uncased`](https://huggingface.co/nreimers/MiniLM-L6-H384-uncased) model. Please refer to the model card for more detailed information about the pre-training procedure.
123
-
124
- ### Fine-tuning
125
-
126
- We fine-tune the model using a contrastive objective. Formally, we compute the cosine similarity from each possible sentence pairs from the batch.
127
- We then apply the cross entropy loss by comparing with true pairs.
128
-
129
- #### Hyper parameters
130
-
131
- We trained our model on a TPU v3-8. We train the model during 100k steps using a batch size of 1024 (128 per TPU core).
132
- We use a learning rate warm up of 500. The sequence length was limited to 128 tokens. We used the AdamW optimizer with
133
- a 2e-5 learning rate. The full training script is accessible in this current repository: `train_script.py`.
134
-
135
- #### Training data
136
-
137
- We use the concatenation from multiple datasets to fine-tune our model. The total number of sentence pairs is above 1 billion sentences.
138
- We sampled each dataset given a weighted probability which configuration is detailed in the `data_config.json` file.
139
-
140
-
141
- | Dataset | Paper | Number of training tuples |
142
- |--------------------------------------------------------|:----------------------------------------:|:--------------------------:|
143
- | [Reddit comments (2015-2018)](https://github.com/PolyAI-LDN/conversational-datasets/tree/master/reddit) | [paper](https://arxiv.org/abs/1904.06472) | 726,484,430 |
144
- | [S2ORC](https://github.com/allenai/s2orc) Citation pairs (Abstracts) | [paper](https://aclanthology.org/2020.acl-main.447/) | 116,288,806 |
145
- | [WikiAnswers](https://github.com/afader/oqa#wikianswers-corpus) Duplicate question pairs | [paper](https://doi.org/10.1145/2623330.2623677) | 77,427,422 |
146
- | [PAQ](https://github.com/facebookresearch/PAQ) (Question, Answer) pairs | [paper](https://arxiv.org/abs/2102.07033) | 64,371,441 |
147
- | [S2ORC](https://github.com/allenai/s2orc) Citation pairs (Titles) | [paper](https://aclanthology.org/2020.acl-main.447/) | 52,603,982 |
148
- | [S2ORC](https://github.com/allenai/s2orc) (Title, Abstract) | [paper](https://aclanthology.org/2020.acl-main.447/) | 41,769,185 |
149
- | [Stack Exchange](https://huggingface.co/datasets/flax-sentence-embeddings/stackexchange_xml) (Title, Body) pairs | - | 25,316,456 |
150
- | [Stack Exchange](https://huggingface.co/datasets/flax-sentence-embeddings/stackexchange_xml) (Title+Body, Answer) pairs | - | 21,396,559 |
151
- | [Stack Exchange](https://huggingface.co/datasets/flax-sentence-embeddings/stackexchange_xml) (Title, Answer) pairs | - | 21,396,559 |
152
- | [MS MARCO](https://microsoft.github.io/msmarco/) triplets | [paper](https://doi.org/10.1145/3404835.3462804) | 9,144,553 |
153
- | [GOOAQ: Open Question Answering with Diverse Answer Types](https://github.com/allenai/gooaq) | [paper](https://arxiv.org/pdf/2104.08727.pdf) | 3,012,496 |
154
- | [Yahoo Answers](https://www.kaggle.com/soumikrakshit/yahoo-answers-dataset) (Title, Answer) | [paper](https://proceedings.neurips.cc/paper/2015/hash/250cf8b51c773f3f8dc8b4be867a9a02-Abstract.html) | 1,198,260 |
155
- | [Code Search](https://huggingface.co/datasets/code_search_net) | - | 1,151,414 |
156
- | [COCO](https://cocodataset.org/#home) Image captions | [paper](https://link.springer.com/chapter/10.1007%2F978-3-319-10602-1_48) | 828,395|
157
- | [SPECTER](https://github.com/allenai/specter) citation triplets | [paper](https://doi.org/10.18653/v1/2020.acl-main.207) | 684,100 |
158
- | [Yahoo Answers](https://www.kaggle.com/soumikrakshit/yahoo-answers-dataset) (Question, Answer) | [paper](https://proceedings.neurips.cc/paper/2015/hash/250cf8b51c773f3f8dc8b4be867a9a02-Abstract.html) | 681,164 |
159
- | [Yahoo Answers](https://www.kaggle.com/soumikrakshit/yahoo-answers-dataset) (Title, Question) | [paper](https://proceedings.neurips.cc/paper/2015/hash/250cf8b51c773f3f8dc8b4be867a9a02-Abstract.html) | 659,896 |
160
- | [SearchQA](https://huggingface.co/datasets/search_qa) | [paper](https://arxiv.org/abs/1704.05179) | 582,261 |
161
- | [Eli5](https://huggingface.co/datasets/eli5) | [paper](https://doi.org/10.18653/v1/p19-1346) | 325,475 |
162
- | [Flickr 30k](https://shannon.cs.illinois.edu/DenotationGraph/) | [paper](https://transacl.org/ojs/index.php/tacl/article/view/229/33) | 317,695 |
163
- | [Stack Exchange](https://huggingface.co/datasets/flax-sentence-embeddings/stackexchange_xml) Duplicate questions (titles) | | 304,525 |
164
- | AllNLI ([SNLI](https://nlp.stanford.edu/projects/snli/) and [MultiNLI](https://cims.nyu.edu/~sbowman/multinli/) | [paper SNLI](https://doi.org/10.18653/v1/d15-1075), [paper MultiNLI](https://doi.org/10.18653/v1/n18-1101) | 277,230 |
165
- | [Stack Exchange](https://huggingface.co/datasets/flax-sentence-embeddings/stackexchange_xml) Duplicate questions (bodies) | | 250,519 |
166
- | [Stack Exchange](https://huggingface.co/datasets/flax-sentence-embeddings/stackexchange_xml) Duplicate questions (titles+bodies) | | 250,460 |
167
- | [Sentence Compression](https://github.com/google-research-datasets/sentence-compression) | [paper](https://www.aclweb.org/anthology/D13-1155/) | 180,000 |
168
- | [Wikihow](https://github.com/pvl/wikihow_pairs_dataset) | [paper](https://arxiv.org/abs/1810.09305) | 128,542 |
169
- | [Altlex](https://github.com/chridey/altlex/) | [paper](https://aclanthology.org/P16-1135.pdf) | 112,696 |
170
- | [Quora Question Triplets](https://quoradata.quora.com/First-Quora-Dataset-Release-Question-Pairs) | - | 103,663 |
171
- | [Simple Wikipedia](https://cs.pomona.edu/~dkauchak/simplification/) | [paper](https://www.aclweb.org/anthology/P11-2117/) | 102,225 |
172
- | [Natural Questions (NQ)](https://ai.google.com/research/NaturalQuestions) | [paper](https://transacl.org/ojs/index.php/tacl/article/view/1455) | 100,231 |
173
- | [SQuAD2.0](https://rajpurkar.github.io/SQuAD-explorer/) | [paper](https://aclanthology.org/P18-2124.pdf) | 87,599 |
174
- | [TriviaQA](https://huggingface.co/datasets/trivia_qa) | - | 73,346 |
175
- | **Total** | | **1,170,060,424** |
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
modeling_baa.py CHANGED
@@ -7,7 +7,7 @@ at no measured quality cost.
7
 
8
  Works for BERT-based and XLM-RoBERTa-based stacks alike: the reranker's encoder submodule is resolved
9
  generically via `reranker.base_model` (so `.bert` / `.roberta` are both handled). Optional per-model query/doc
10
- prompts are read from config.json (e.g. arctic uses "query: ").
11
 
12
  Usage:
13
  from modeling_baa import BaaEmbeddingReranker
@@ -49,6 +49,10 @@ class BaaEmbeddingReranker:
49
  base.embeddings.word_embeddings.weight.data = shared_wemb.to(self.reranker.dtype).clone()
50
  self.reranker.to(self.device).eval()
51
  self.rr_tok = AutoTokenizer.from_pretrained(rr_dir, trust_remote_code=trc)
 
 
 
 
52
 
53
  def embed(self, texts, is_query=False, batch_size=32):
54
  """Return L2-normalized bi-encoder vectors. Applies the model's query/doc prompt if configured."""
 
7
 
8
  Works for BERT-based and XLM-RoBERTa-based stacks alike: the reranker's encoder submodule is resolved
9
  generically via `reranker.base_model` (so `.bert` / `.roberta` are both handled). Optional per-model query/doc
10
+ prompts are read from config.json (e.g. some models use a "query: " prefix).
11
 
12
  Usage:
13
  from modeling_baa import BaaEmbeddingReranker
 
49
  base.embeddings.word_embeddings.weight.data = shared_wemb.to(self.reranker.dtype).clone()
50
  self.reranker.to(self.device).eval()
51
  self.rr_tok = AutoTokenizer.from_pretrained(rr_dir, trust_remote_code=trc)
52
+ # Weights may be stored fp16 on disk (smaller artifact); CPU can't compute in half -> upcast to fp32.
53
+ if str(self.device) == "cpu":
54
+ self.embedder = self.embedder.to(torch.float32)
55
+ self.reranker = self.reranker.float()
56
 
57
  def embed(self, texts, is_query=False, batch_size=32):
58
  """Return L2-normalized bi-encoder vectors. Applies the model's query/doc prompt if configured."""