diff --git a/docs_new/cookbook/autoregressive/StepFun/Step-3.7-Flash.mdx b/docs_new/cookbook/autoregressive/StepFun/Step-3.7-Flash.mdx
new file mode 100644
index 000000000..5870b7c98
--- /dev/null
+++ b/docs_new/cookbook/autoregressive/StepFun/Step-3.7-Flash.mdx
@@ -0,0 +1,324 @@
+---
+title: Step-3.7-Flash (new)
+metatags:
+ description: "Deploy Step-3.7-Flash multimodal reasoning engine with SGLang."
+---
+
+import { Step37FlashDeployment } from '/src/snippets/autoregressive/step-37-flash-deployment.jsx';
+
+## 1. Model Introduction
+
+[Step-3.7-Flash](https://huggingface.co/stepfun-ai/Step-3.7-Flash) is a 198B-parameter Mixture-of-Experts (MoE) vision-language model that combines a 196B-parameter language backbone with a 1.8B-parameter vision encoder for native image understanding. Engineered for high-frequency production workloads, it activates approximately 11B parameters per token and supports a 256k context window with three selectable reasoning levels (low, medium, and high). The model is available in multiple quantization formats (BF16, FP8, NVFP4).
+
+Step-3.7-Flash is built for developers who need to scale agentic workflows that combine perception, search, and reasoning — from parsing massive financial reports in one pass, to running multi-step search loops with cross-source verification, to operating concurrent coding agents in high-throughput pipelines.
+
+## 2. SGLang Installation
+
+Step-3.7-Flash is currently available in SGLang via Docker image install.
+
+### Docker (NVIDIA)
+```bash Command
+# Pull the docker image
+docker pull lmsysorg/sglang:dev-pr-18084
+
+# Launch the container
+docker run -it --gpus all \
+ --shm-size=32g \
+ --ipc=host \
+ --network=host \
+ lmsysorg/sglang:dev-pr-18084 bash
+```
+
+## 3. Model Deployment
+
+This section provides deployment configurations optimized for different use cases.
+
+### 3.1 Basic Configuration
+
+The Step-3.7-Flash series comes in one size with multiple quantization options. Recommended starting configurations vary depending on hardware.
+
+**Interactive Command Generator**: Use the configuration selector below to automatically generate the appropriate deployment command for your hardware platform, quantization method, and capabilities.
+
+
+
+### 3.2 Configuration Tips
+
+- **Memory**: Requires GPUs with high VRAM capacity. Supported platforms: H200 (4x, TP=4), B200/B300 (4x, TP=4), GB200/GB300 (4x, TP=4).
+- **NVFP4 Quantization**: NVFP4 provides the smallest memory footprint. Requires `--quantization modelopt_fp4 --kv-cache-dtype fp8_e4m3 --moe-runner-backend flashinfer_trtllm`.
+- **Trust Remote Code**: All Step-3.7-Flash variants require `--trust-remote-code` due to the custom model architecture.
+
+## 4. Model Invocation
+
+### 4.1 Basic Usage
+
+For basic API usage and request examples, please refer to:
+
+- [SGLang Basic Usage Guide](../../../docs/basic_usage/send_request)
+- [SGLang OpenAI Vision API Guide](../../../docs/basic_usage/openai_api_vision)
+
+### 4.2 Advanced Usage
+
+#### 4.2.1 Multi-Modal Inputs
+
+Step-3.7-Flash supports image inputs alongside text. Here's a basic example:
+
+```python Example
+import time
+from openai import OpenAI
+
+client = OpenAI(
+ api_key="EMPTY",
+ base_url="http://localhost:30000/v1",
+ timeout=3600
+)
+
+messages = [
+ {
+ "role": "user",
+ "content": [
+ {
+ "type": "image_url",
+ "image_url": {
+ "url": "https://ofasys-multimodal-wlcb-3-toshanghai.oss-accelerate.aliyuncs.com/wpf272043/keepme/image/receipt.png"
+ }
+ },
+ {
+ "type": "text",
+ "text": "Read all the text in the image."
+ }
+ ]
+ }
+]
+
+start = time.time()
+response = client.chat.completions.create(
+ model="stepfun-ai/Step-3.7-Flash",
+ messages=messages,
+ max_tokens=2048,
+)
+print(f"Response costs: {time.time() - start:.2f}s")
+print(f"Generated text: {response.choices[0].message.content}")
+```
+
+**Multi-Image Input Example:**
+
+Step-3.7-Flash can process multiple images in a single request for comparison or analysis:
+
+```python Example
+import time
+from openai import OpenAI
+
+client = OpenAI(
+ api_key="EMPTY",
+ base_url="http://localhost:30000/v1",
+ timeout=3600
+)
+
+messages = [
+ {
+ "role": "user",
+ "content": [
+ {
+ "type": "image_url",
+ "image_url": {
+ "url": "https://www.civitatis.com/f/china/hong-kong/guia/taxi.jpg"
+ }
+ },
+ {
+ "type": "image_url",
+ "image_url": {
+ "url": "https://cdn.cheapoguides.com/wp-content/uploads/sites/7/2025/05/GettyImages-509614603-1280x600.jpg"
+ }
+ },
+ {
+ "type": "text",
+ "text": "Compare these two images and describe the differences in 100 words or less."
+ }
+ ]
+ }
+]
+
+start = time.time()
+response = client.chat.completions.create(
+ model="stepfun-ai/Step-3.7-Flash",
+ messages=messages,
+ max_tokens=2048,
+)
+print(f"Response costs: {time.time() - start:.2f}s")
+print(f"Generated text: {response.choices[0].message.content}")
+```
+
+#### 4.2.2 Reasoning Parser
+
+Step-3.7-Flash supports reasoning mode. Enable the reasoning parser during deployment to separate the thinking and content sections:
+
+```shell Command
+sglang serve \
+ --model-path stepfun-ai/Step-3.7-Flash \
+ --tp 4 \
+ --trust-remote-code \
+ --reasoning-parser step3p5
+```
+
+```python Example
+from openai import OpenAI
+
+client = OpenAI(
+ base_url="http://localhost:30000/v1",
+ api_key="EMPTY"
+)
+
+# Enable streaming to see the thinking process in real-time
+response = client.chat.completions.create(
+ model="stepfun-ai/Step-3.7-Flash",
+ messages=[
+ {"role": "user", "content": "Solve this problem step by step: What is 15% of 240?"}
+ ],
+ temperature=0.7,
+ max_tokens=2048,
+ stream=True
+)
+
+# Process the stream
+has_thinking = False
+has_answer = False
+thinking_started = False
+
+for chunk in response:
+ if chunk.choices and len(chunk.choices) > 0:
+ delta = chunk.choices[0].delta
+
+ # Print thinking process
+ if hasattr(delta, 'reasoning_content') and delta.reasoning_content:
+ if not thinking_started:
+ print("=============== Thinking =================", flush=True)
+ thinking_started = True
+ has_thinking = True
+ print(delta.reasoning_content, end="", flush=True)
+
+ # Print answer content
+ if delta.content:
+ # Close thinking section and add content header
+ if has_thinking and not has_answer:
+ print("\n=============== Content =================", flush=True)
+ has_answer = True
+ print(delta.content, end="", flush=True)
+
+print()
+```
+
+#### 4.2.3 Tool Calling
+
+Step-3.7-Flash supports tool calling capabilities. Enable the tool call parser:
+
+**Start sglang server:**
+
+```shell Command
+sglang serve \
+ --model-path stepfun-ai/Step-3.7-Flash \
+ --tp 4 \
+ --trust-remote-code \
+ --reasoning-parser step3p5 \
+ --tool-call-parser step3p5
+```
+
+```python Example
+from openai import OpenAI
+import json
+
+client = OpenAI(
+ base_url="http://localhost:30000/v1",
+ api_key="EMPTY"
+)
+
+# 1. define tools
+tools = [
+ {
+ "type": "function",
+ "function": {
+ "name": "get_weather",
+ "description": "Get the current weather for a location",
+ "parameters": {
+ "type": "object",
+ "properties": {
+ "location": {"type": "string", "description": "The city name"},
+ "unit": {"type": "string", "enum": ["celsius", "fahrenheit"], "description": "Temperature unit"}
+ },
+ "required": ["location"]
+ }
+ }
+ }
+]
+
+# 2. tool run
+def get_weather(location, unit="celsius"):
+ return f"The weather in {location} is 22 {unit[0].upper()} and sunny."
+
+# 3. send first request
+print("--- Sending first request ---")
+response = client.chat.completions.create(
+ model="stepfun-ai/Step-3.7-Flash",
+ messages=[
+ {"role": "user", "content": "What's the weather in Beijing?"}
+ ],
+ tools=tools,
+ temperature=1.0,
+ stream=False
+)
+
+message = response.choices[0].message
+
+# 4. Handle Reasoning Content
+reasoning = getattr(message, 'reasoning_content', None)
+if reasoning:
+ print("=============== Thinking =================")
+ print(reasoning)
+ print("==========================================")
+
+# 5. Handle Tool Calls
+if message.tool_calls:
+ print("\nTool Calls detected:")
+ history_messages = [
+ {"role": "user", "content": "What's the weather in Beijing?"},
+ message
+ ]
+
+ for tool_call in message.tool_calls:
+ print(f" Tool: {tool_call.function.name}")
+ print(f" Args: {tool_call.function.arguments}")
+
+ args = json.loads(tool_call.function.arguments)
+ tool_result = get_weather(args.get("location"), args.get("unit", "celsius"))
+
+ history_messages.append({
+ "role": "tool",
+ "tool_call_id": tool_call.id,
+ "content": tool_result
+ })
+
+ print("\n--- Sending tool results ---")
+ final_response = client.chat.completions.create(
+ model="stepfun-ai/Step-3.7-Flash",
+ messages=history_messages,
+ temperature=1.0,
+ stream=False
+ )
+
+ print("=============== Final Content =================")
+ print(final_response.choices[0].message.content)
+
+else:
+ if message.content:
+ print("=============== Content =================")
+ print(message.content)
+```
+
+**Note:**
+
+- The reasoning parser shows how the model decides to use a tool
+- Tool calls are clearly marked with the function name and arguments
+- You can then execute the function and send the result back to continue the conversation
+
+## 5. Benchmark
+
+*Benchmark results will be added soon.*
diff --git a/docs_new/cookbook/autoregressive/StepFun/Step3.5.mdx b/docs_new/cookbook/autoregressive/StepFun/Step3.5.mdx
index 176c2bf96..82c8a1d5a 100644
--- a/docs_new/cookbook/autoregressive/StepFun/Step3.5.mdx
+++ b/docs_new/cookbook/autoregressive/StepFun/Step3.5.mdx
@@ -1,5 +1,5 @@
---
-title: Step-3.5
+title: Step-3.5-Flash
metatags:
description: "Deploy Step-3.5 reasoning engine with SGLang. "
---
diff --git a/docs_new/docs.json b/docs_new/docs.json
index 91c5aafcc..09a37e672 100644
--- a/docs_new/docs.json
+++ b/docs_new/docs.json
@@ -1034,6 +1034,7 @@
{
"group": "StepFun",
"pages": [
+ "cookbook/autoregressive/StepFun/Step-3.7-Flash",
"cookbook/autoregressive/StepFun/Step3.5",
"cookbook/autoregressive/StepFun/Step3-VL-10B"
]
diff --git a/docs_new/src/snippets/autoregressive/step-37-flash-deployment.jsx b/docs_new/src/snippets/autoregressive/step-37-flash-deployment.jsx
new file mode 100644
index 000000000..355c8d7c2
--- /dev/null
+++ b/docs_new/src/snippets/autoregressive/step-37-flash-deployment.jsx
@@ -0,0 +1,394 @@
+export const Step37FlashDeployment = () => {
+ const options = {
+ hardware: {
+ name: 'hardware',
+ title: 'Hardware Platform',
+ items: [
+ { id: 'hopper', label: 'Hopper', default: true },
+ { id: 'b200_b300', label: 'B200/B300', default: false },
+ { id: 'gb200_gb300', label: 'GB200/GB300', default: false }
+ ]
+ },
+ quantization: {
+ name: 'quantization',
+ title: 'Quantization',
+ getDynamicItems: (values) => {
+ const isHopper = values.hardware === 'hopper';
+ return [
+ { id: 'bf16', label: 'BF16', default: true },
+ { id: 'fp8', label: 'FP8', default: false },
+ ...(isHopper ? [] : [{ id: 'nvfp4', label: 'NVFP4', default: false }])
+ ];
+ }
+ },
+ reasoningParser: {
+ name: 'reasoningParser',
+ title: 'Reasoning Parser',
+ items: [
+ { id: 'disabled', label: 'Disabled', default: true },
+ { id: 'enabled', label: 'Enabled', default: false }
+ ],
+ commandRule: (value) => value === 'enabled' ? '--reasoning-parser step3p5' : null
+ },
+ toolcall: {
+ name: 'toolcall',
+ title: 'Tool Call Parser',
+ items: [
+ { id: 'disabled', label: 'Disabled', default: true },
+ { id: 'enabled', label: 'Enabled', default: false }
+ ],
+ commandRule: (value) => value === 'enabled' ? '--tool-call-parser step3p5' : null
+ },
+ speculative: {
+ name: 'speculative',
+ title: 'Speculative Decoding',
+ getDynamicItems: (values) => {
+ const isNVFP4 = values.quantization === 'nvfp4';
+ return [
+ { id: 'disabled', label: 'Disabled', default: true },
+ { id: 'enabled', label: 'Enabled', default: false, disabled: isNVFP4, disabledReason: 'Not supported with NVFP4' }
+ ];
+ },
+ commandRule: (value) => {
+ if (value !== 'enabled') return null;
+
+ let cmd = '--speculative-algorithm EAGLE \\\n --speculative-num-steps 3 \\\n --speculative-eagle-topk 1 \\\n --speculative-num-draft-tokens 4 \\\n --enable-multi-layer-eagle ';
+
+ return cmd;
+ }
+ }
+ };
+
+ const generateCommand = (values) => {
+ const { hardware, quantization } = values;
+ const isNVFP4 = quantization === 'nvfp4';
+ const quantSuffix = quantization === 'fp8' ? '-FP8' : quantization === 'nvfp4' ? '-NVFP4' : '';
+ const modelName = `stepfun-ai/Step-3.7-Flash${quantSuffix}`;
+ const tpValue = hardware === 'gb200_gb300' ? 4 : 8;
+
+ let cmd = '';
+
+ cmd += 'sglang serve \\\n';
+ cmd += ` --model-path ${modelName}`;
+
+ if (tpValue > 1) {
+ cmd += ` \\\n --tp ${tpValue}`;
+ }
+ // EP required for FP8 and NVFP4
+ if (quantSuffix === '-FP8' || isNVFP4) {
+ cmd += ` \\\n --ep ${tpValue}`;
+ }
+
+ // NVFP4 requires additional flags (Blackwell only)
+ if (isNVFP4) {
+ cmd += ' \\\n --moe-runner-backend flashinfer_trtllm';
+ cmd += ' \\\n --kv-cache-dtype fp8_e4m3';
+ cmd += ' \\\n --quantization modelopt_fp4';
+ cmd += ' \\\n --attention-backend trtllm_mha';
+ }
+
+ // Trust remote code for custom architecture
+ cmd += ' \\\n --trust-remote-code';
+
+ for (const [key, option] of Object.entries(options)) {
+ if (option.commandRule) {
+ const rule = option.commandRule(values[key], values);
+
+ if (rule) {
+ cmd += ` \\\n ${rule}`;
+ }
+ }
+ }
+
+ return cmd;
+ };
+
+ const getInitialState = () => {
+ const initialState = {};
+ Object.entries(options).forEach(([key, option]) => {
+ if (option.type === 'checkbox') {
+ initialState[key] = (option.items || [])
+ .filter((item) => item.default)
+ .map((item) => item.id);
+ return;
+ }
+ if (option.type === 'text') {
+ initialState[key] = option.default || '';
+ return;
+ }
+ let items = option.items || [];
+ if (option.getDynamicItems) {
+ const defaultValues = {};
+ Object.entries(options).forEach(([innerKey, innerOption]) => {
+ if (innerOption.type === 'checkbox') {
+ defaultValues[innerKey] = (innerOption.items || [])
+ .filter((item) => item.default)
+ .map((item) => item.id);
+ } else if (innerOption.type === 'text') {
+ defaultValues[innerKey] = innerOption.default || '';
+ } else if (innerOption.items && innerOption.items.length > 0) {
+ const defaultItem = innerOption.items.find((item) => item.default);
+ defaultValues[innerKey] = defaultItem ? defaultItem.id : innerOption.items[0].id;
+ }
+ });
+ items = option.getDynamicItems(defaultValues);
+ }
+ const defaultItem = items && items.find((item) => item.default);
+ initialState[key] = defaultItem ? defaultItem.id : items && items[0] ? items[0].id : '';
+ });
+ return initialState;
+ };
+
+ const [values, setValues] = useState(getInitialState);
+ const [isDark, setIsDark] = useState(false);
+
+ useEffect(() => {
+ const checkDarkMode = () => {
+ const html = document.documentElement;
+ const isDarkMode =
+ html.classList.contains('dark') ||
+ html.getAttribute('data-theme') === 'dark' ||
+ html.style.colorScheme === 'dark';
+ setIsDark(isDarkMode);
+ };
+ checkDarkMode();
+ const observer = new MutationObserver(checkDarkMode);
+ observer.observe(document.documentElement, {
+ attributes: true,
+ attributeFilter: ['class', 'data-theme', 'style'],
+ });
+ return () => observer.disconnect();
+ }, []);
+
+ const handleRadioChange = (optionName, value) => {
+ setValues((prev) => {
+ const next = { ...prev, [optionName]: value };
+ // Reset nvfp4 to bf16 when switching to Hopper
+ if (optionName === 'hardware' && value === 'hopper' && prev.quantization === 'nvfp4') {
+ next.quantization = 'bf16';
+ }
+ // Reset speculative to disabled when switching to nvfp4
+ if (optionName === 'quantization' && value === 'nvfp4' && prev.speculative === 'enabled') {
+ next.speculative = 'disabled';
+ }
+ return next;
+ });
+ };
+
+ const handleCheckboxChange = (optionName, itemId, isChecked) => {
+ setValues((prev) => {
+ const currentValues = prev[optionName] || [];
+ if (isChecked) {
+ return { ...prev, [optionName]: [...currentValues, itemId] };
+ }
+ return {
+ ...prev,
+ [optionName]: currentValues.filter((id) => id !== itemId),
+ };
+ });
+ };
+
+ const handleTextChange = (optionName, value) => {
+ setValues((prev) => ({ ...prev, [optionName]: value }));
+ };
+
+ const command = generateCommand(values);
+
+ const containerStyle = {
+ maxWidth: '900px',
+ margin: '0 auto',
+ display: 'flex',
+ flexDirection: 'column',
+ gap: '4px',
+ };
+ const cardStyle = {
+ padding: '8px 12px',
+ border: `1px solid ${isDark ? '#374151' : '#e5e7eb'}`,
+ borderLeft: `3px solid ${isDark ? '#E85D4D' : '#D45D44'}`,
+ borderRadius: '4px',
+ display: 'flex',
+ alignItems: 'center',
+ gap: '12px',
+ background: isDark ? '#1f2937' : '#fff',
+ };
+ const titleStyle = {
+ fontSize: '13px',
+ fontWeight: '600',
+ minWidth: '140px',
+ flexShrink: 0,
+ color: isDark ? '#e5e7eb' : 'inherit',
+ };
+ const itemsStyle = {
+ display: 'flex',
+ rowGap: '2px',
+ columnGap: '6px',
+ flexWrap: 'wrap',
+ alignItems: 'center',
+ flex: 1,
+ };
+ const labelBaseStyle = {
+ padding: '4px 10px',
+ border: `1px solid ${isDark ? '#9ca3af' : '#d1d5db'}`,
+ borderRadius: '3px',
+ cursor: 'pointer',
+ display: 'inline-flex',
+ flexDirection: 'column',
+ alignItems: 'center',
+ justifyContent: 'center',
+ fontWeight: '500',
+ fontSize: '13px',
+ transition: 'all 0.2s',
+ userSelect: 'none',
+ minWidth: '45px',
+ textAlign: 'center',
+ flex: 1,
+ background: isDark ? '#374151' : '#fff',
+ color: isDark ? '#e5e7eb' : 'inherit',
+ };
+ const checkedStyle = {
+ background: '#D45D44',
+ color: 'white',
+ borderColor: '#D45D44',
+ };
+ const disabledStyle = {
+ cursor: 'not-allowed',
+ opacity: 0.5,
+ };
+ const subtitleStyle = {
+ display: 'block',
+ fontSize: '9px',
+ marginTop: '1px',
+ lineHeight: '1.1',
+ opacity: 0.7,
+ };
+ const textInputStyle = {
+ flex: 1,
+ padding: '8px 10px',
+ borderRadius: '4px',
+ border: `1px solid ${isDark ? '#4b5563' : '#d1d5db'}`,
+ background: isDark ? '#111827' : '#fff',
+ color: isDark ? '#e5e7eb' : '#111827',
+ fontSize: '13px',
+ };
+ const commandDisplayStyle = {
+ flex: 1,
+ padding: '12px 16px',
+ background: isDark ? '#111827' : '#f5f5f5',
+ borderRadius: '6px',
+ fontFamily: "'Menlo', 'Monaco', 'Courier New', monospace",
+ fontSize: '12px',
+ lineHeight: '1.5',
+ color: isDark ? '#e5e7eb' : '#374151',
+ whiteSpace: 'pre-wrap',
+ overflowX: 'auto',
+ margin: 0,
+ border: `1px solid ${isDark ? '#374151' : '#e5e7eb'}`,
+ };
+
+ return (
+
+ {Object.entries(options).map(([key, option]) => {
+ if (option.condition && !option.condition(values)) {
+ return null;
+ }
+ const items = option.getDynamicItems ? option.getDynamicItems(values) : option.items || [];
+ return (
+
+ );
+ })}
+
+
Run this Command:
+
{command}
+
+
+ );
+};
diff --git a/python/sglang/srt/configs/__init__.py b/python/sglang/srt/configs/__init__.py
index c9043f7ea..70b1c2ebc 100644
--- a/python/sglang/srt/configs/__init__.py
+++ b/python/sglang/srt/configs/__init__.py
@@ -37,6 +37,7 @@ from sglang.srt.configs.step3_vl import (
Step3VLConfig,
)
from sglang.srt.configs.step3p5 import Step3p5Config
+from sglang.srt.configs.step3p7 import Step3p7Config
__all__ = [
"AfmoeConfig",
@@ -76,5 +77,6 @@ __all__ = [
"JetNemotronConfig",
"JetVLMConfig",
"Step3p5Config",
+ "Step3p7Config",
"Qwen3ASRConfig",
]
diff --git a/python/sglang/srt/configs/model_config.py b/python/sglang/srt/configs/model_config.py
index 713dab9e1..a94b6638a 100644
--- a/python/sglang/srt/configs/model_config.py
+++ b/python/sglang/srt/configs/model_config.py
@@ -452,6 +452,12 @@ class ModelConfig:
self.hf_config.architectures[0] = "MiMoV2MTP"
if is_draft_model and self.hf_config.architectures[0] == "Step3p5ForCausalLM":
self.hf_config.architectures[0] = "Step3p5MTP"
+ if (
+ is_draft_model
+ and self.hf_config.architectures[0] == "Step3p7ForConditionalGeneration"
+ ):
+ self.hf_config = self.hf_text_config
+ self.hf_config.architectures = ["Step3p5MTP"]
if is_draft_model and self.hf_config.architectures[0] in [
"BailingMoeV2ForCausalLM",
"BailingMoeForCausalLM",
@@ -1557,6 +1563,7 @@ multimodal_model_archs = [
"PaddleOCRVLForConditionalGeneration",
"MiDashengLMModel",
"StepVLForConditionalGeneration",
+ "Step3p7ForConditionalGeneration",
"KimiK25ForConditionalGeneration",
]
@@ -1671,6 +1678,7 @@ def is_hybrid_swa_model(model_architectures: List[str]):
"MiMoV2MTP",
"Step3p5ForCausalLM",
"Step3p5MTP",
+ "Step3p7ForConditionalGeneration",
"Gemma4ForCausalLM",
"Gemma4ForConditionalGeneration",
"LagunaForCausalLM",
@@ -1709,7 +1717,10 @@ def get_hybrid_layer_ids(
elif "MiMoV2MTP" in model_architectures:
swa_attention_layer_ids = [0]
full_attention_layer_ids = []
- elif "Step3p5ForCausalLM" in model_architectures:
+ elif (
+ "Step3p5ForCausalLM" in model_architectures
+ or "Step3p7ForConditionalGeneration" in model_architectures
+ ):
layer_types = hf_text_config.layer_types
swa_attention_layer_ids = [
i
diff --git a/python/sglang/srt/configs/step3p5.py b/python/sglang/srt/configs/step3p5.py
index d33572255..0e5704b8b 100644
--- a/python/sglang/srt/configs/step3p5.py
+++ b/python/sglang/srt/configs/step3p5.py
@@ -28,6 +28,7 @@ class Step3p5Config(PretrainedConfig):
norm_expert_weight: bool = True,
layer_types: list[str] = None,
sliding_window: Optional[int] = None,
+ yarn_only_types: Optional[list[str]] = None,
moe_layers_enum: tuple[int] = (
3,
4,
@@ -94,6 +95,7 @@ class Step3p5Config(PretrainedConfig):
self.moe_layers_enum = moe_layers_enum
self.layer_types = layer_types
self.sliding_window = sliding_window
+ self.yarn_only_types = yarn_only_types or []
# The upstream Step-3.5-Flash config has layer_types with 48 entries
# but num_hidden_layers=45. The extra 3 are for MTP/nextn predict
# layers (indices 45-47) used by Step3p5DecoderLayer during EAGLE
diff --git a/python/sglang/srt/configs/step3p7.py b/python/sglang/srt/configs/step3p7.py
new file mode 100644
index 000000000..0d215117c
--- /dev/null
+++ b/python/sglang/srt/configs/step3p7.py
@@ -0,0 +1,97 @@
+from typing import Optional, Union
+
+from transformers.configuration_utils import PretrainedConfig
+
+
+class Step3p7VisionEncoderConfig(PretrainedConfig):
+ model_type = "perception_encoder"
+
+ def __init__(
+ self,
+ width=1536,
+ layers=47,
+ heads=16,
+ num_channels=3,
+ image_size=728,
+ patch_size=14,
+ mlp_ratio=8960 / 1536,
+ hidden_act="quick_gelu",
+ layer_norm_eps=1e-5,
+ use_cls_token=False,
+ use_ln_pre=True,
+ use_ln_post=False,
+ use_abs_posemb=True,
+ use_rope2d=True,
+ ls_init_value=0.1,
+ output_dim=None,
+ pool_type="none",
+ **kwargs,
+ ):
+ self.width = width
+ self.layers = layers
+ self.heads = heads
+ self.num_channels = num_channels
+ self.patch_size = patch_size
+ self.image_size = image_size
+ self.mlp_ratio = mlp_ratio
+ self.layer_norm_eps = layer_norm_eps
+ self.hidden_act = hidden_act
+ self.use_cls_token = use_cls_token
+ self.use_ln_pre = use_ln_pre
+ self.use_ln_post = use_ln_post
+ self.use_abs_posemb = use_abs_posemb
+ self.use_rope2d = use_rope2d
+ self.ls_init_value = ls_init_value
+ self.output_dim = output_dim
+ self.pool_type = pool_type
+ super().__init__(**kwargs)
+
+
+class Step3p7Config(PretrainedConfig):
+ model_type = "step3p7"
+
+ def __init__(
+ self,
+ vision_config: Optional[Union[dict, Step3p7VisionEncoderConfig]] = None,
+ text_config: Optional[Union[dict, PretrainedConfig]] = None,
+ understand_projector_stride: int = 2,
+ projector_bias: bool = False,
+ image_token_id: int = 128001,
+ image_token_len: int = 169,
+ patch_token_len: int = 81,
+ im_start_token: str = "",
+ im_end_token: str = "",
+ im_patch_token: str = "",
+ use_im_start_end: bool = True,
+ vision_select_layer: int = -1,
+ **kwargs,
+ ) -> None:
+ if vision_config is None:
+ vision_config = Step3p7VisionEncoderConfig()
+ elif isinstance(vision_config, dict):
+ vision_config = Step3p7VisionEncoderConfig(**vision_config)
+ self.vision_config = vision_config
+
+ if text_config is None:
+ from sglang.srt.configs.step3p5 import Step3p5Config
+
+ text_config = Step3p5Config()
+ elif isinstance(text_config, dict):
+ from sglang.srt.configs.step3p5 import Step3p5Config
+
+ text_config = Step3p5Config(**text_config)
+ self.text_config = text_config
+
+ self.understand_projector_stride = understand_projector_stride
+ self.projector_bias = projector_bias
+ self.hidden_size = text_config.hidden_size
+ self.image_token_id = image_token_id
+ self.image_token_len = image_token_len
+ self.patch_token_len = patch_token_len
+ self.im_start_token = im_start_token
+ self.im_end_token = im_end_token
+ self.im_patch_token = im_patch_token
+ self.use_im_start_end = use_im_start_end
+ self.vision_select_layer = vision_select_layer
+
+ super().__init__(**kwargs)
diff --git a/python/sglang/srt/layers/moe/moe_runner/flashinfer_trtllm.py b/python/sglang/srt/layers/moe/moe_runner/flashinfer_trtllm.py
index 4e65c2a67..997d3ccf6 100644
--- a/python/sglang/srt/layers/moe/moe_runner/flashinfer_trtllm.py
+++ b/python/sglang/srt/layers/moe/moe_runner/flashinfer_trtllm.py
@@ -900,6 +900,18 @@ def fused_experts_none_to_flashinfer_trtllm_fp4(
runner_config.activation, is_gated=runner_config.is_gated
)
+ # Build per-expert clamp-limit tensor from the per-layer scalar.
+ _clamp_val = runner_config.gemm1_clamp_limit
+ if _clamp_val is not None:
+ gemm1_clamp_limit = torch.full(
+ (quant_info.local_num_experts,),
+ _clamp_val,
+ dtype=torch.float32,
+ device=hs_fp4.device,
+ )
+ else:
+ gemm1_clamp_limit = None
+
num_tokens = hs_fp4.shape[0]
hidden_size = (
hs_fp4.shape[-1] * 2 if hs_fp4.dtype == torch.uint8 else hs_fp4.shape[-1]
@@ -924,6 +936,10 @@ def fused_experts_none_to_flashinfer_trtllm_fp4(
num_tokens, hidden_size, dtype=hidden_states.dtype, device=hs_fp4.device
)
+ # Fall back to routed path when topk was already materialized (e.g. sigmoid routing).
+ if not use_routed_topk and TopKOutputChecker.format_is_standard(topk_output):
+ use_routed_topk = True
+
if use_routed_topk:
assert TopKOutputChecker.format_is_standard(topk_output)
@@ -940,7 +956,7 @@ def fused_experts_none_to_flashinfer_trtllm_fp4(
gemm1_bias=None,
gemm1_alpha=None,
gemm1_beta=None,
- gemm1_clamp_limit=None,
+ gemm1_clamp_limit=gemm1_clamp_limit,
gemm2_weights=quant_info.w2_weight,
gemm2_weights_scale=quant_info.w2_weight_scale.view(torch.float8_e4m3fn),
gemm2_bias=None,
@@ -984,7 +1000,7 @@ def fused_experts_none_to_flashinfer_trtllm_fp4(
gemm1_bias=None,
gemm1_alpha=None,
gemm1_beta=None,
- gemm1_clamp_limit=None,
+ gemm1_clamp_limit=gemm1_clamp_limit,
gemm2_weights=quant_info.w2_weight,
gemm2_weights_scale=quant_info.w2_weight_scale.view(torch.float8_e4m3fn),
gemm2_bias=None,
diff --git a/python/sglang/srt/layers/moe/token_dispatcher/standard.py b/python/sglang/srt/layers/moe/token_dispatcher/standard.py
index caf99571d..39b592b4a 100644
--- a/python/sglang/srt/layers/moe/token_dispatcher/standard.py
+++ b/python/sglang/srt/layers/moe/token_dispatcher/standard.py
@@ -99,6 +99,7 @@ class StandardDispatcher(BaseDispatcher):
self.skip_local_expert_mapping = (
backend.is_flashinfer_cutlass()
or backend.is_flashinfer_cutedsl()
+ or backend.is_flashinfer_trtllm()
or backend.is_flashinfer_trtllm_routed()
or self.enable_flashinfer_mxfp4_moe
)
diff --git a/python/sglang/srt/managers/scheduler.py b/python/sglang/srt/managers/scheduler.py
index 868a28d43..135d254d9 100644
--- a/python/sglang/srt/managers/scheduler.py
+++ b/python/sglang/srt/managers/scheduler.py
@@ -688,6 +688,7 @@ class Scheduler(
"num_experts_per_tok",
"num_experts_per_token",
"top_k_experts",
+ "moe_top_k",
)
if any(hasattr(config_to_check, attr) for attr in moe_topk_attrs):
initialize_moe_config(self.server_args)
diff --git a/python/sglang/srt/models/step3p5.py b/python/sglang/srt/models/step3p5.py
index 1f3a4d221..843c2d862 100644
--- a/python/sglang/srt/models/step3p5.py
+++ b/python/sglang/srt/models/step3p5.py
@@ -12,6 +12,7 @@ from sglang.srt.distributed import (
tensor_model_parallel_all_reduce,
)
from sglang.srt.eplb.expert_distribution import get_global_expert_distribution_recorder
+from sglang.srt.eplb.expert_location import ModelConfigForExpertLocation
from sglang.srt.eplb.expert_location_dispatch import ExpertLocationDispatchInfo
from sglang.srt.layers.activation import SiluAndMul
from sglang.srt.layers.communicator import LayerCommunicator, LayerScatterModes
@@ -225,6 +226,8 @@ class Step3p5MoEMLP(nn.Module):
# router_logits: (batch * sequence_length, n_experts)
router_logits, _ = self.gate(hidden_states)
topk_output = self.topk(hidden_states, router_logits)
+ if hasattr(topk_output, "to_standard"):
+ topk_output = topk_output.to_standard(layer_id=self.layer_id)
if self.routed_scaling_factor != 1.0:
topk_output = StandardTopKOutput(
topk_weights=topk_output.topk_weights * self.routed_scaling_factor,
@@ -794,6 +797,13 @@ class Step3p5ForCausalLM(nn.Module):
"up_proj": ("gate_up_proj", 1),
}
+ @classmethod
+ def get_model_config_for_expert_location(cls, config):
+ return ModelConfigForExpertLocation(
+ num_layers=config.num_hidden_layers,
+ num_logical_experts=config.moe_num_experts,
+ )
+
def __init__(
self,
config: Step3p5Config,
@@ -1019,7 +1029,13 @@ class Step3p5ForCausalLM(nn.Module):
)
loaded_params.add(actual_param_name)
- print_params = set(params_dict.keys()) - loaded_params
+ # Derived parameters (e.g. blockscale_swizzled from NVFP4 quantization)
+ # are computed in process_weights_after_loading, not loaded from checkpoint.
+ print_params = {
+ p
+ for p in set(params_dict.keys()) - loaded_params
+ if "blockscale_swizzled" not in p
+ }
assert len(print_params) == 0, f"Some parameters are not loaded: {print_params}"
def get_embed_and_head(self):
diff --git a/python/sglang/srt/models/step3p7.py b/python/sglang/srt/models/step3p7.py
new file mode 100644
index 000000000..5dd0816f7
--- /dev/null
+++ b/python/sglang/srt/models/step3p7.py
@@ -0,0 +1,200 @@
+from typing import Iterable, List, Optional, Tuple
+
+import torch
+from torch import nn
+from transformers.activations import ACT2FN
+
+from sglang.srt.configs.step3p7 import Step3p7Config
+from sglang.srt.layers.linear import ColumnParallelLinear
+from sglang.srt.layers.quantization.base_config import QuantizationConfig
+from sglang.srt.managers.mm_utils import (
+ MultiModalityDataPaddingPatternMultimodalTokens,
+ general_mm_embed_routine,
+)
+from sglang.srt.managers.schedule_batch import (
+ Modality,
+ MultimodalDataItem,
+ MultimodalInputs,
+)
+from sglang.srt.model_executor.forward_batch_info import ForwardBatch
+from sglang.srt.model_loader.weight_utils import default_weight_loader
+from sglang.srt.models.step3_vl_10b import PerceptionEncoder
+from sglang.srt.models.step3p5 import Step3p5ForCausalLM
+from sglang.srt.models.utils import WeightsMapper
+from sglang.srt.utils import add_prefix
+
+
+class Step3p7ForConditionalGeneration(nn.Module):
+
+ # NVFP4 checkpoints (e.g. huangyu-nv/step3p7-nvfp4-moe-only-kvfp8) use
+ # "model.language_model." prefix, while sglang parameters are named
+ # "language_model.model.". This mapper remaps the quantization ignore
+ # patterns so that is_layer_skipped works correctly.
+ hf_to_sglang_mapper = WeightsMapper(
+ orig_to_new_prefix={
+ "model.language_model.": "language_model.model.",
+ "model.vision_model": "vision_model",
+ "model.vit_large_projector": "vit_large_projector",
+ }
+ )
+
+ @classmethod
+ def get_model_config_for_expert_location(cls, config):
+ return Step3p5ForCausalLM.get_model_config_for_expert_location(
+ config.text_config
+ )
+
+ def __init__(
+ self,
+ config: Step3p7Config,
+ quant_config: Optional[QuantizationConfig] = None,
+ prefix: str = "",
+ ):
+ super().__init__()
+ self.config = config
+
+ self.vision_model = PerceptionEncoder(
+ config.vision_config,
+ ACT2FN[config.vision_config.hidden_act],
+ quant_config=None, # Vision weights are not quantized
+ prefix=add_prefix("vision_model", prefix),
+ )
+ self.vit_large_projector = ColumnParallelLinear(
+ config.vision_config.width * 4,
+ config.text_config.hidden_size,
+ bias=config.projector_bias,
+ gather_output=True,
+ quant_config=None, # Projector weights are bf16
+ prefix=add_prefix("vit_large_projector", prefix),
+ )
+ self.language_model = Step3p5ForCausalLM(
+ config=config.text_config,
+ quant_config=quant_config,
+ prefix=add_prefix("language_model", prefix),
+ )
+
+ def _get_vision_model_output(self, input_tensor: torch.Tensor) -> torch.Tensor:
+ return self.vision_model(input_tensor)
+
+ @property
+ def device(self) -> torch.device:
+ return self.vit_large_projector.weight.device
+
+ def _flatten_embeddings(self, embeddings) -> torch.Tensor:
+ if isinstance(embeddings, torch.Tensor):
+ return embeddings.flatten(0, -2)
+ return torch.cat(tuple(self._flatten_embeddings(t) for t in embeddings))
+
+ def _process_image_features(self, image_features: torch.Tensor) -> torch.Tensor:
+ image_features, _ = self.vit_large_projector(image_features)
+ return image_features
+
+ def get_image_feature(self, items: List[MultimodalDataItem]) -> torch.Tensor:
+ assert len(items) == 1
+
+ item = items[0]
+ pixel_values = item.feature.type(self.vision_model.dtype)
+ num_patches = item.model_specific_data.get("num_patches")
+ patch_pixel_values = item.model_specific_data.get("patch_pixel_values", None)
+ if patch_pixel_values is not None:
+ patch_pixel_values = patch_pixel_values.type(self.vision_model.dtype).to(
+ self.device
+ )
+
+ image_features = self._get_vision_model_output(pixel_values)
+ patch_image_features = (
+ self._get_vision_model_output(patch_pixel_values)
+ if patch_pixel_values is not None
+ else None
+ )
+ image_features = self._process_image_features(image_features)
+ patch_image_features = (
+ self._process_image_features(patch_image_features)
+ if patch_image_features is not None
+ else None
+ )
+ merged_image_features = []
+ cur_patch_idx = 0
+ for i, num_patch in enumerate(num_patches):
+ cur_feature = []
+ if num_patch > 0:
+ patch_slice = patch_image_features[
+ cur_patch_idx : cur_patch_idx + num_patch
+ ]
+ cur_feature.append(patch_slice.view(-1, patch_slice.shape[-1]))
+ cur_feature.append(image_features[i].view(-1, image_features.shape[-1]))
+ cur_patch_idx += num_patch
+ merged_image_features.append(
+ torch.cat(cur_feature) if len(cur_feature) > 1 else cur_feature[0]
+ )
+ return self._flatten_embeddings(merged_image_features)
+
+ def pad_input_ids(self, input_ids: List[int], mm_inputs: MultimodalInputs):
+ pattern = MultiModalityDataPaddingPatternMultimodalTokens()
+ return pattern.pad_input_tokens(input_ids, mm_inputs)
+
+ def forward(
+ self,
+ input_ids: torch.Tensor,
+ positions: torch.Tensor,
+ forward_batch: ForwardBatch,
+ get_embedding: bool = False,
+ ):
+ hidden_states = general_mm_embed_routine(
+ input_ids=input_ids,
+ forward_batch=forward_batch,
+ language_model=self.language_model,
+ data_embedding_funcs={
+ Modality.IMAGE: self.get_image_feature,
+ },
+ positions=positions,
+ )
+ return hidden_states
+
+ def get_embed_and_head(self):
+ return self.language_model.get_embed_and_head()
+
+ def set_embed_and_head(self, embed, head):
+ self.language_model.set_embed_and_head(embed, head)
+
+ def load_weights(self, weights: Iterable[Tuple[str, torch.Tensor]]):
+ weights = list(weights)
+
+ vision_weights = []
+ language_weights = []
+
+ for name, loaded_weight in weights:
+ # NVFP4 checkpoints use "model.language_model." prefix for
+ # language weights and "model.vision_model." for vision weights,
+ # while FP8 checkpoints use "model." and "vision_model." directly.
+ name = name.replace("language_model.", "", 1)
+
+ if "vision_model" in name or "vit_large_projector" in name:
+ # Strip leading "model." for vision weights (NVFP4 format)
+ if name.startswith("model."):
+ name = name[len("model.") :]
+ name = name.replace(r".attn.in_proj_weight", r".attn.qkv_proj.weight")
+ name = name.replace(r".attn.in_proj_bias", r".attn.qkv_proj.bias")
+ name = name.replace(r".attn.out_proj.bias", r".attn.proj.bias")
+ name = name.replace(r".attn.out_proj.weight", r".attn.proj.weight")
+ name = name.replace(".mlp.c_fc", ".mlp.fc1")
+ name = name.replace(".mlp.c_proj", ".mlp.fc2")
+ vision_weights.append((name, loaded_weight))
+ else:
+ language_weights.append((name, loaded_weight))
+
+ # Load vision tower weights
+ params_dict = dict(self.named_parameters(remove_duplicate=False))
+ for name, loaded_weight in vision_weights:
+ if name not in params_dict:
+ raise ValueError(f"Weight {name} not found in params_dict")
+ param = params_dict[name]
+ weight_loader = getattr(param, "weight_loader", default_weight_loader)
+ weight_loader(param, loaded_weight)
+
+ # Load language model weights
+ if language_weights:
+ self.language_model.load_weights(language_weights)
+
+
+EntryClass = Step3p7ForConditionalGeneration
diff --git a/python/sglang/srt/multimodal/processors/step3_vl.py b/python/sglang/srt/multimodal/processors/step3_vl.py
index e1e14d16f..eb76e4bed 100644
--- a/python/sglang/srt/multimodal/processors/step3_vl.py
+++ b/python/sglang/srt/multimodal/processors/step3_vl.py
@@ -14,6 +14,7 @@ from transformers import BatchFeature, ProcessorMixin, TensorType
from sglang.srt.managers.schedule_batch import MultimodalProcessorOutput
from sglang.srt.models.step3_vl import Step3VLForConditionalGeneration
from sglang.srt.models.step3_vl_10b import StepVLForConditionalGeneration
+from sglang.srt.models.step3p7 import Step3p7ForConditionalGeneration
from sglang.srt.multimodal.processors.base_processor import (
BaseMultimodalProcessor as SGLangBaseProcessor,
)
@@ -520,7 +521,11 @@ class Step3VLProcessor:
class Step3VLImageProcessor(SGLangBaseProcessor):
- models = [Step3VLForConditionalGeneration, StepVLForConditionalGeneration]
+ models = [
+ Step3VLForConditionalGeneration,
+ StepVLForConditionalGeneration,
+ Step3p7ForConditionalGeneration,
+ ]
def __init__(self, hf_config, server_args, _processor, *args, **kwargs):
# TODO, check _processor is tokenizer or processor.
diff --git a/python/sglang/srt/server_args.py b/python/sglang/srt/server_args.py
index 4f5dd3456..6fd058607 100644
--- a/python/sglang/srt/server_args.py
+++ b/python/sglang/srt/server_args.py
@@ -2211,7 +2211,21 @@ class ServerArgs:
logger.warning(
"Disable hybrid SWA memory for MiMoV2 model with hierarchical cache"
)
- elif "Step3p5ForCausalLM" in model_arch:
+ elif (
+ "Step3p5ForCausalLM" in model_arch
+ or "Step3p7ForConditionalGeneration" in model_arch
+ ):
+ if self.is_attention_backend_not_set():
+ if is_blackwell_supported():
+ self.attention_backend = "fa4"
+ logger.info(
+ "Auto-select fa4 attention backend for Step3p7 on Blackwell."
+ )
+ elif is_sm90_supported():
+ self.attention_backend = "fa3"
+ logger.info(
+ "Auto-select fa3 attention backend for Step3p7 on Hopper."
+ )
if self.speculative_algorithm == "EAGLE":
self.enable_multi_layer_eagle = True
logger.info(
diff --git a/python/sglang/srt/utils/common.py b/python/sglang/srt/utils/common.py
index de149625a..cb6e908b6 100644
--- a/python/sglang/srt/utils/common.py
+++ b/python/sglang/srt/utils/common.py
@@ -2969,6 +2969,7 @@ def is_fa3_default_architecture(hf_config):
"GlmOcrForConditionalGeneration",
"Step3VLForConditionalGeneration",
"StepVLForConditionalGeneration",
+ "Step3p7ForConditionalGeneration",
"MiMoV2ForCausalLM",
"MiMoV2FlashForCausalLM",
}
diff --git a/python/sglang/srt/utils/hf_transformers/common.py b/python/sglang/srt/utils/hf_transformers/common.py
index 0fd841888..1f93ae852 100644
--- a/python/sglang/srt/utils/hf_transformers/common.py
+++ b/python/sglang/srt/utils/hf_transformers/common.py
@@ -52,6 +52,7 @@ from sglang.srt.configs import (
Qwen3_5MoeConfig,
Qwen3NextConfig,
Step3p5Config,
+ Step3p7Config,
Step3VLConfig,
)
from sglang.srt.configs.deepseek_ocr import DeepseekVLV2Config
@@ -106,6 +107,7 @@ _CONFIG_REGISTRY: Dict[str, Type[PretrainedConfig]] = {
JetVLMConfig,
KimiK25Config,
Step3p5Config,
+ Step3p7Config,
MiniCPMV4_6Config,
MiniCPMV4_6VisionConfig,
]