From c121428c58cc4aba44d239b8362f56231c4ce112 Mon Sep 17 00:00:00 2001
From: Markus Fritsche <fritsche.markus@gmail.com>
Date: Mon, 15 Jun 2026 15:12:25 +0200
Subject: [PATCH] Initial commit: Boltzmann LLM proxy with compression +
 classifier middleware

- llm-proxy.py v4: aggregator with classify/compress endpoints, gemma4 backend
- classifier-server.py: Llama 3.2 1B query complexity classifier
- compress-server.py: token-budget compression middleware
- start-proxy.sh / start.sh: launcher scripts
---
 .gitignore           |   5 +
 classifier-server.py | 106 ++++++++++++
 compress-server.py   | 176 ++++++++++++++++++++
 download-models.sh   |  22 +++
 launch-qwen35-npu.sh |  12 ++
 llm-proxy.py         | 379 +++++++++++++++++++++++++++++++++++++++++++
 start-proxy.sh       |   6 +
 start.sh             |   6 +
 8 files changed, 712 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 classifier-server.py
 create mode 100644 compress-server.py
 create mode 100755 download-models.sh
 create mode 100755 launch-qwen35-npu.sh
 create mode 100755 llm-proxy.py
 create mode 100755 start-proxy.sh
 create mode 100755 start.sh

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..acca56f
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,5 @@
+*.gguf
+*.log
+llamafile
+*.bak-*
+__pycache__/
diff --git a/classifier-server.py b/classifier-server.py
new file mode 100644
index 0000000..bdba037
--- /dev/null
+++ b/classifier-server.py
@@ -0,0 +1,106 @@
+#!/usr/bin/env python3
+"""Query classifier service wrapping Llama 3.2 1B on :8089.
+
+Endpoints:
+  POST /classify  {"query": str} → {"tier": "low"|"medium"|"high"}
+  GET  /health                   → {"status": "ok"}
+"""
+import http.server
+import json
+import os
+import sys
+import time
+import urllib.request
+import urllib.error
+
+CLASSIFIER_URL = os.getenv("CLASSIFIER_URL", "http://127.0.0.1:8089/v1/chat/completions")
+LISTEN_PORT = int(os.getenv("CLASSIFIER_LISTEN_PORT", "8090"))
+
+FEW_SHOT_EXAMPLES = [
+    ("What is 2+2?", "low"),
+    ("List the files in the current directory", "low"),
+    ("What is the weather today?", "low"),
+    ("Write a Python function to sort a list of dictionaries by a key", "medium"),
+    ("Explain how garbage collection works in Go", "medium"),
+    ("Debug this error: TypeError: 'NoneType' object is not subscriptable", "medium"),
+    ("Deploy the new release to production", "high"),
+    ("Roll back the last database migration", "high"),
+    ("Commit and push all changes to main branch", "high"),
+]
+
+
+def log(msg):
+    sys.stderr.write(f"{time.strftime('%H:%M:%S')} {msg}\n")
+    sys.stderr.flush()
+
+
+def build_messages(query):
+    msgs = [{"role": "system", "content": "Classify queries as low, medium, or high."}]
+    for q, a in FEW_SHOT_EXAMPLES:
+        msgs.append({"role": "user", "content": q})
+        msgs.append({"role": "assistant", "content": a})
+    msgs.append({"role": "user", "content": query})
+    return msgs
+
+
+def classify(query):
+    body = json.dumps({
+        "model": "llama-3.2-1b-classifier",
+        "messages": build_messages(query),
+        "max_tokens": 5,
+        "temperature": 0,
+    }).encode()
+    req = urllib.request.Request(CLASSIFIER_URL, data=body, headers={
+        "Content-Type": "application/json",
+    })
+    try:
+        resp = urllib.request.urlopen(req, timeout=30)
+        data = json.loads(resp.read())
+        content = data["choices"][0]["message"]["content"].strip().lower()
+        if content in ("low", "medium", "high"):
+            return content
+        log(f"unexpected classifier output: {content!r} for query {query!r}")
+        return "medium"
+    except (urllib.error.URLError, json.JSONDecodeError, KeyError, IndexError) as e:
+        log(f"classifier error: {e}")
+        return "medium"
+
+
+class Handler(http.server.BaseHTTPRequestHandler):
+    server_version = "classifier/1"
+
+    def _read_body(self):
+        n = int(self.headers.get("Content-Length", 0))
+        return json.loads(self.rfile.read(n)) if n else {}
+
+    def _json_response(self, code, data):
+        payload = json.dumps(data).encode()
+        self.send_response(code)
+        self.send_header("Content-Type", "application/json")
+        self.send_header("Content-Length", str(len(payload)))
+        self.end_headers()
+        self.wfile.write(payload)
+
+    def do_GET(self):
+        if self.path == "/health":
+            return self._json_response(200, {"status": "ok"})
+        self._json_response(404, {"error": "not found"})
+
+    def do_POST(self):
+        if self.path == "/classify":
+            body = self._read_body()
+            query = body.get("query", "")
+            if not query:
+                return self._json_response(400, {"error": "missing query"})
+            tier = classify(query)
+            log(f"classify {query[:60]!r} -> {tier}")
+            return self._json_response(200, {"tier": tier})
+        self._json_response(404, {"error": "not found"})
+
+    def log_message(self, fmt, *args):
+        return
+
+
+if __name__ == "__main__":
+    log(f"classifier-server on :{LISTEN_PORT}, backend {CLASSIFIER_URL}")
+    http.server.ThreadingHTTPServer(("0.0.0.0", LISTEN_PORT), Handler).serve_forever()
diff --git a/compress-server.py b/compress-server.py
new file mode 100644
index 0000000..17317ab
--- /dev/null
+++ b/compress-server.py
@@ -0,0 +1,176 @@
+#!/usr/bin/env python3
+"""Prompt compression service using XLM-RoBERTa-large (LLMLingua-2).
+
+Scoring approach: runs the classification head on each token, drops tokens
+with low keep-probability. The compressed text is reconstructed from the
+kept token spans.
+
+Endpoints:
+  POST /compress  {"messages": [...], "rate": 0.5} → {"compressed": [...], "stats": {...}}
+  GET  /health                                      → {"status": "ok"}
+"""
+import http.server
+import json
+import os
+import sys
+import time
+import re
+import math
+
+import torch
+import numpy as np
+from transformers import AutoTokenizer, AutoModelForTokenClassification
+
+MODEL_NAME = os.getenv("COMPRESS_MODEL", "microsoft/llmlingua-2-xlm-roberta-large-meetingbank")
+LISTEN_PORT = int(os.getenv("COMPRESS_LISTEN_PORT", "8091"))
+DEVICE = "cpu"
+DTYPE = torch.float16
+
+
+def log(msg):
+    sys.stderr.write(f"{time.strftime('%H:%M:%S')} {msg}\n")
+    sys.stderr.flush()
+
+
+# ── model loading ─────────────────────────────────────────────────
+
+log(f"loading model {MODEL_NAME} ...")
+t0 = time.time()
+tokenizer = AutoTokenizer.from_pretrained(MODEL_NAME)
+model = AutoModelForTokenClassification.from_pretrained(
+    MODEL_NAME, torch_dtype=DTYPE
+).to(DEVICE).eval()
+log(f"model loaded in {time.time()-t0:.1f}s ({sum(p.numel() for p in model.parameters())/1e6:.0f}M params)")
+
+
+# ── compression core ──────────────────────────────────────────────
+
+def _merge_token_spans(text, keep_mask, tokens):
+    """Reconstruct text from kept tokens, merging subwords cleanly."""
+    kept = []
+    for i, (tok, keep) in enumerate(zip(tokens, keep_mask)):
+        if not keep:
+            continue
+        piece = tok
+        # Remove prefix space indicator for merged tokens
+        if i > 0 and piece.startswith("##"):
+            piece = piece[2:]
+        elif i > 0 and not piece.startswith(" ") and not re.match(r'^[^\w]', piece):
+            piece = " " + piece
+        kept.append(piece)
+    return "".join(kept).strip()
+
+
+def compress_text(text, rate=0.5):
+    """Compress a single text string, targeting `rate` compression ratio (0-1)."""
+    inputs = tokenizer(text, return_tensors="pt", truncation=True, max_length=2048).to(DEVICE)
+    input_ids = inputs["input_ids"][0]
+    n_tokens = len(input_ids)
+
+    with torch.no_grad():
+        outputs = model(**inputs)
+        logits = outputs.logits[0]  # (seq_len, num_labels)
+
+    # For binary classification: label 0 = keep, 1 = drop
+    keep_probs = torch.softmax(logits, dim=-1)[:, 0]  # probability of keep
+    probs = keep_probs.cpu().numpy()
+
+    # Don't drop special tokens ([CLS], [SEP], [PAD])
+    special_ids = {tokenizer.cls_token_id, tokenizer.sep_token_id,
+                   tokenizer.pad_token_id, tokenizer.bos_token_id,
+                   tokenizer.eos_token_id, tokenizer.unk_token_id,
+                   0}  # padding
+    is_special = [id.item() in special_ids for id in input_ids]
+
+    # Target: keep rate * (1-rate) tokens (rate=0.5 means keep half)
+    n_to_keep = max(1, int(n_tokens * (1 - rate)))
+
+    # Mask: force-keep special tokens, then keep top-k by probability
+    keep = np.zeros(n_tokens, dtype=bool)
+    for i in range(n_tokens):
+        if is_special[i]:
+            keep[i] = True
+
+    n_kept_special = keep.sum()
+    n_remaining = n_to_keep - n_kept_special
+
+    if n_remaining > 0:
+        # Get indices of non-special tokens sorted by keep probability
+        non_special_idx = [i for i in range(n_tokens) if not is_special[i]]
+        sorted_idx = sorted(non_special_idx, key=lambda i: probs[i], reverse=True)
+        for i in sorted_idx[:n_remaining]:
+            keep[i] = True
+
+    # Decode kept tokens
+    tokens = tokenizer.convert_ids_to_tokens(input_ids)
+    compressed = _merge_token_spans(text, keep, tokens)
+
+    return {
+        "compressed": compressed,
+        "original_tokens": int(n_tokens),
+        "compressed_tokens": int(keep.sum()),
+        "ratio": float(keep.sum() / n_tokens),
+    }
+
+
+def compress_messages(messages, rate=0.5):
+    """Compress an array of chat messages. Drops low-info tokens from each."""
+    compressed = []
+    for msg in messages:
+        role = msg.get("role", "user")
+        content = msg.get("content", "")
+        if content:
+            result = compress_text(content, rate)
+            compressed.append({"role": role, "content": result["compressed"]})
+        else:
+            compressed.append(msg)
+    return compressed
+
+
+# ── HTTP handler ─────────────────────────────────────────────────
+
+class Handler(http.server.BaseHTTPRequestHandler):
+    server_version = "compress-server/1"
+
+    def _read_body(self):
+        n = int(self.headers.get("Content-Length", 0))
+        return json.loads(self.rfile.read(n)) if n else {}
+
+    def _json_response(self, code, data):
+        payload = json.dumps(data, default=str).encode()
+        self.send_response(code)
+        self.send_header("Content-Type", "application/json")
+        self.send_header("Content-Length", str(len(payload)))
+        self.end_headers()
+        self.wfile.write(payload)
+
+    def do_GET(self):
+        if self.path == "/health":
+            return self._json_response(200, {"status": "ok"})
+        self._json_response(404, {"error": "not found"})
+
+    def do_POST(self):
+        if self.path == "/compress":
+            body = self._read_body()
+            messages = body.get("messages", [])
+            rate = float(body.get("rate", 0.5))
+            if not messages:
+                return self._json_response(400, {"error": "missing messages"})
+            t0 = time.time()
+            compressed = compress_messages(messages, rate)
+            elapsed = time.time() - t0
+            log(f"compress {len(messages)} msgs rate={rate} in {elapsed:.2f}s")
+            return self._json_response(200, {
+                "compressed": compressed,
+                "rate": rate,
+                "elapsed_s": round(elapsed, 2),
+            })
+        self._json_response(404, {"error": "not found"})
+
+    def log_message(self, fmt, *args):
+        return
+
+
+if __name__ == "__main__":
+    log(f"compress-server on :{LISTEN_PORT}")
+    http.server.ThreadingHTTPServer(("0.0.0.0", LISTEN_PORT), Handler).serve_forever()
diff --git a/download-models.sh b/download-models.sh
new file mode 100755
index 0000000..aa06fa4
--- /dev/null
+++ b/download-models.sh
@@ -0,0 +1,22 @@
+#!/bin/bash
+set -e
+cd ~/npu
+URLS=(
+  "Codestral-22B-v0.1-Q4_K_M.gguf|https://huggingface.co/bartowski/Codestral-22B-v0.1-GGUF/resolve/main/Codestral-22B-v0.1-Q4_K_M.gguf"
+  "gpt-oss-20b-mxfp4.gguf|https://huggingface.co/ggml-org/gpt-oss-20b-GGUF/resolve/main/gpt-oss-20b-mxfp4.gguf"
+  "DeepSeek-Coder-V2-Lite-Instruct-Q4_K_M.gguf|https://huggingface.co/bartowski/DeepSeek-Coder-V2-Lite-Instruct-GGUF/resolve/main/DeepSeek-Coder-V2-Lite-Instruct-Q4_K_M.gguf"
+  "starcoder2-15b-instruct-v0.1-Q4_K_M.gguf|https://huggingface.co/bartowski/starcoder2-15b-instruct-v0.1-GGUF/resolve/main/starcoder2-15b-instruct-v0.1-Q4_K_M.gguf"
+)
+for entry in "${URLS[@]}"; do
+  fname="${entry%%|*}"
+  url="${entry##*|}"
+  if [[ -f "$fname" && $(stat -c%s "$fname") -gt 1000000000 ]]; then
+    echo "[$(date +%H:%M:%S)] SKIP $fname (already $(du -h "$fname" | cut -f1))"
+    continue
+  fi
+  echo "[$(date +%H:%M:%S)] START $fname"
+  wget -c -O "$fname" "$url" 2>&1 | tail -5
+  echo "[$(date +%H:%M:%S)] DONE  $fname ($(du -h "$fname" | cut -f1))"
+done
+echo "[$(date +%H:%M:%S)] ALL DONE"
+ls -lh ~/npu/*.gguf
diff --git a/launch-qwen35-npu.sh b/launch-qwen35-npu.sh
new file mode 100755
index 0000000..94cbcce
--- /dev/null
+++ b/launch-qwen35-npu.sh
@@ -0,0 +1,12 @@
+#!/bin/bash
+# Manual launcher for the NPU Qwen 3.5 9B llama-server backend.
+# Used for ad-hoc testing; the systemd user unit
+# llama-server-qwen35-npu.service is the production path.
+set -e
+ulimit -n 65536
+exec /home/mfritsche/src/rk-llama.cpp/build/bin/llama-server \
+  -m /home/mfritsche/models/Qwen3.5-9B-Q8_0.gguf \
+  --alias qwen3.5-9b-npu \
+  --reasoning off \
+  -c 4096 -t 4 \
+  --host 0.0.0.0 --port 8086
diff --git a/llm-proxy.py b/llm-proxy.py
new file mode 100755
index 0000000..1ec5669
--- /dev/null
+++ b/llm-proxy.py
@@ -0,0 +1,379 @@
+#!/usr/bin/env python3
+"""Boltzmann-local LLM aggregator with compression + classifier middleware.
+
+Behaviour (unchanged from v2):
+  - GET  /v1/models         : merged model list from every reachable backend
+  - POST /v1/chat/completions : routes by model name; compresses gemma4 messages
+  - POST /v1/completions    : same routing rule
+
+New:
+  - POST /v1/classify       : calls local Llama 3.2 1B classifier
+  - POST /v1/compress       : token-budget compression of chat messages
+"""
+import http.server
+import http.client
+import json
+import os
+import sys
+import time
+import urllib.request
+import urllib.error
+
+BACKENDS = [
+    ("gemma4-12b-q4km", "127.0.0.1", 8087),
+    ("classifier-1b", "127.0.0.1", 8089),
+    ("coder-1.5b",    "127.0.0.1", 8081),
+    ("llama-3.1",     "127.0.0.1", 8083),
+    ("nemo-12b",      "127.0.0.1", 8084),
+    ("qwen3-30b-a3b", "127.0.0.1", 8085),
+    ("qwen3.5-9b-npu", "127.0.0.1", 8086),
+]
+CONNECT_TIMEOUT = 30
+READ_TIMEOUT = 1800
+LISTEN_PORT = int(os.getenv("LLM_PROXY_PORT", "8082"))
+CLASSIFIER_URL = os.getenv("CLASSIFIER_URL", "http://127.0.0.1:8090/classify")
+COMPRESS_URL = os.getenv("COMPRESS_URL", "http://127.0.0.1:8091/compress")
+
+# Gemma 4 12B context limit - reserve 4096 for completion
+GEMMA_MAX_INPUT_TOKENS = 65536 - 4096
+
+FEW_SHOT_EXAMPLES = [
+    ("What is 2+2?", "low"),
+    ("List the files in the current directory", "low"),
+    ("What is the weather today?", "low"),
+    ("Write a Python function to sort a list of dictionaries by a key", "medium"),
+    ("Explain how garbage collection works in Go", "medium"),
+    ("Debug this error: TypeError: 'NoneType' object is not subscriptable", "medium"),
+    ("Deploy the new release to production", "high"),
+    ("Roll back the last database migration", "high"),
+    ("Commit and push all changes to main branch", "high"),
+]
+
+
+def log(msg):
+    sys.stdout.write(f"{time.strftime('%H:%M:%S')} {msg}\n")
+    sys.stdout.flush()
+
+
+# ── helpers ────────────────────────────────────────────────────────
+
+def _simple_token_estimate(text):
+    """Rough token estimate: 4 chars per token (standard heuristic)."""
+    return len(text) // 4
+
+
+def compress_messages(messages, max_tokens=GEMMA_MAX_INPUT_TOKENS):
+    """Drop oldest non-system messages to stay within token budget."""
+    if not messages:
+        return messages
+
+    system_msgs = [m for m in messages if m.get("role") == "system"]
+    history = [m for m in messages if m.get("role") != "system"]
+
+    # Count current tokens
+    total = sum(_simple_token_estimate(json.dumps(m)) for m in messages)
+
+    if total <= max_tokens:
+        return messages
+
+    # Drop oldest history messages, keep most recent
+    while history and total > max_tokens:
+        dropped = history.pop(0)
+        total -= _simple_token_estimate(json.dumps(dropped))
+        log(f"compress: dropped {dropped.get('role','?')} msg ({total} est. tokens remain)")
+
+    compressed = system_msgs + history
+    return compressed if compressed else messages
+
+
+def classify_query(query):
+    """Send query to the local classifier service. Returns tier string."""
+    body = json.dumps({"query": query}).encode()
+    req = urllib.request.Request(
+        CLASSIFIER_URL, data=body,
+        headers={"Content-Type": "application/json"},
+    )
+    try:
+        resp = urllib.request.urlopen(req, timeout=15)
+        data = json.loads(resp.read())
+        return data.get("tier", "medium")
+    except (urllib.error.URLError, json.JSONDecodeError, OSError) as e:
+        log(f"classifier call failed: {e}")
+        return "medium"
+
+
+def compress_via_service(messages, rate=0.4):
+    """Send messages to the ML compression service. Returns compressed messages or None."""
+    body = json.dumps({"messages": messages, "rate": rate}).encode()
+    req = urllib.request.Request(
+        COMPRESS_URL, data=body,
+        headers={"Content-Type": "application/json"},
+    )
+    try:
+        resp = urllib.request.urlopen(req, timeout=5)  # fast timeout, fall back to truncation
+        data = json.loads(resp.read())
+        return data.get("compressed")
+    except (urllib.error.URLError, json.JSONDecodeError, OSError) as e:
+        log(f"compress service call failed: {e}")
+        return None
+
+
+def classify_local(query):
+    """Fallback: classify directly against Llama 3.2 1B if classifier service is unavailable."""
+    url = "http://127.0.0.1:8089/v1/chat/completions"
+    msgs = [{"role": "system", "content": "Classify queries as low, medium, or high."}]
+    for q, a in FEW_SHOT_EXAMPLES:
+        msgs.append({"role": "user", "content": q})
+        msgs.append({"role": "assistant", "content": a})
+    msgs.append({"role": "user", "content": query})
+    body = json.dumps({
+        "model": "llama-3.2-1b-classifier",
+        "messages": msgs,
+        "max_tokens": 5,
+        "temperature": 0,
+    }).encode()
+    req = urllib.request.Request(url, data=body, headers={"Content-Type": "application/json"})
+    try:
+        resp = urllib.request.urlopen(req, timeout=30)
+        data = json.loads(resp.read())
+        content = data["choices"][0]["message"]["content"].strip().lower()
+        return content if content in ("low", "medium", "high") else "medium"
+    except Exception as e:
+        log(f"direct classify failed: {e}")
+        return "medium"
+
+
+# ── model discovery ────────────────────────────────────────────────
+
+def fetch_models(backend):
+    name, host, port = backend
+    try:
+        c = http.client.HTTPConnection(host, port, timeout=CONNECT_TIMEOUT)
+        c.request("GET", "/v1/models")
+        r = c.getresponse()
+        if r.status != 200:
+            return None
+        data = json.loads(r.read())
+        c.close()
+        ids = []
+        for m in data.get("data", []) or data.get("models", []):
+            mid = m.get("id") or m.get("name") or m.get("model")
+            if mid:
+                ids.append(mid)
+        return ids
+    except (OSError, ValueError, http.client.HTTPException):
+        return None
+
+
+def discover():
+    out = []
+    for b in BACKENDS:
+        ids = fetch_models(b)
+        if ids is not None:
+            out.append((b, ids))
+    return out
+
+
+def find_backend_for_model(model_id):
+    for b in BACKENDS:
+        ids = fetch_models(b)
+        if ids and model_id in ids:
+            return b
+    return None
+
+
+# ── HTTP handler ──────────────────────────────────────────────────
+
+class Handler(http.server.BaseHTTPRequestHandler):
+    server_version = "boltzmann-llm-proxy/3"
+
+    def _read_body(self):
+        n = int(self.headers.get("Content-Length", 0))
+        return self.rfile.read(n) if n else b""
+
+    def _json_body(self):
+        try:
+            return json.loads(self._read_body())
+        except (ValueError, TypeError):
+            return {}
+
+    def _fwd_headers(self, body_len):
+        h = {}
+        for k in ("Content-Type", "Authorization", "Accept", "Accept-Encoding"):
+            v = self.headers.get(k)
+            if v:
+                h[k] = v
+        if body_len:
+            h["Content-Length"] = str(body_len)
+        return h
+
+    def _json_response(self, code, data):
+        payload = json.dumps(data).encode()
+        self.send_response(code)
+        self.send_header("Content-Type", "application/json")
+        self.send_header("Content-Length", str(len(payload)))
+        self.end_headers()
+        self.wfile.write(payload)
+
+    def _proxy_to(self, backend, method, body, extra_headers=None):
+        name, host, port = backend
+        try:
+            headers = self._fwd_headers(len(body))
+            if extra_headers:
+                headers.update(extra_headers)
+            c = http.client.HTTPConnection(host, port, timeout=READ_TIMEOUT)
+            c.request(method, self.path, body=body, headers=headers)
+            r = c.getresponse()
+            data = r.read()
+            self.send_response(r.status)
+            for hname in ("Content-Type", "Content-Encoding", "Cache-Control", "ETag", "Last-Modified"):
+                v = r.getheader(hname)
+                if v:
+                    self.send_header(hname, v)
+            self.send_header("Content-Length", str(len(data)))
+            self.send_header("X-Backend", name)
+            self.end_headers()
+            self.wfile.write(data)
+            c.close()
+            log(f"{method} {self.path} -> {name} ({r.status})")
+        except (OSError, http.client.HTTPException) as e:
+            self.send_response(502)
+            self.send_header("Content-Type", "application/json")
+            self.send_header("X-Backend", name)
+            self.end_headers()
+            self.wfile.write(json.dumps({"error": f"{name} unreachable: {e}"}).encode())
+            log(f"{method} {self.path} -> {name} FAILED ({e})")
+
+    # ── GET ──
+
+    def do_GET(self):
+        path = self.path.rstrip("/")
+        if path == "/v1/models":
+            merged = []
+            seen = set()
+            for backend, ids in discover():
+                name = backend[0]
+                for mid in ids:
+                    if mid in seen:
+                        continue
+                    seen.add(mid)
+                    merged.append({
+                        "id": mid,
+                        "object": "model",
+                        "owned_by": f"boltzmann/{name}",
+                    })
+            self._json_response(200, {"object": "list", "data": merged})
+            log(f"GET /v1/models -> aggregator ({len(merged)} models)")
+            return
+
+        if path == "/health":
+            self._json_response(200, {"status": "ok", "version": 3})
+            return
+
+        for b in BACKENDS:
+            if fetch_models(b) is not None:
+                return self._proxy_to(b, "GET", b"")
+        self._json_response(502, {"error": "no backend up"})
+
+    # ── POST ──
+
+    def do_POST(self):
+        path = self.path.rstrip("/")
+
+        # ── Classification endpoint ──
+        if path == "/v1/classify":
+            body = self._json_body()
+            query = body.get("query", "")
+            if not query:
+                return self._json_response(400, {"error": "missing query"})
+            tier = classify_local(query)
+            log(f"classify {query[:60]!r} -> {tier}")
+            return self._json_response(200, {"tier": tier})
+
+        # ── Compression endpoint ──
+        if path == "/v1/compress":
+            body = self._json_body()
+            messages = body.get("messages", [])
+            max_tokens = body.get("max_tokens", GEMMA_MAX_INPUT_TOKENS)
+            compressed = compress_messages(messages, max_tokens)
+            ratio = 0
+            if messages:
+                orig = sum(_simple_token_estimate(json.dumps(m)) for m in messages)
+                new = sum(_simple_token_estimate(json.dumps(m)) for m in compressed)
+                ratio = round((1 - new / orig) * 100, 1) if orig else 0
+            return self._json_response(200, {
+                "messages": compressed,
+                "original_tokens": orig if messages else 0,
+                "compressed_tokens": sum(_simple_token_estimate(json.dumps(m)) for m in compressed),
+                "ratio_pct": ratio,
+            })
+
+        # ── Chat / Completions ──
+        if path in ("/v1/chat/completions", "/v1/completions"):
+            body = self._read_body()
+            model = None
+            try:
+                model = json.loads(body).get("model")
+            except (ValueError, TypeError):
+                pass
+
+            target = None
+            if model:
+                target = find_backend_for_model(model)
+                if target is None:
+                    available = sorted({m for b in BACKENDS for m in (fetch_models(b) or [])})
+                    return self._json_response(404, {"error": {
+                        "message": f"model '{model}' not available on this aggregator",
+                        "type": "model_not_found",
+                        "available": available,
+                    }})
+
+            if target is None:
+                for b in BACKENDS:
+                    if fetch_models(b) is not None:
+                        target = b
+                        break
+            if target is None:
+                return self._json_response(502, {"error": "no backend up"})
+
+            # Compression: try ML service (fast timeout), fall back to token-budget truncation
+            compressed_body = body
+            if path == "/v1/chat/completions" and "gemma4" in (model or ""):
+                try:
+                    req = json.loads(body)
+                    if "messages" in req and len(req["messages"]) > 2:
+                        orig_n = len(req["messages"])
+                        orig_t = sum(_simple_token_estimate(json.dumps(m)) for m in req["messages"])
+                        compressed = compress_via_service(req["messages"], rate=0.4)
+                        if compressed:
+                            req["messages"] = compressed
+                            compressed_body = json.dumps(req).encode()
+                            new_t = sum(_simple_token_estimate(json.dumps(m)) for m in compressed)
+                            log(f"ML compress {model}: ~{orig_t}->{new_t} tokens")
+                        else:
+                            truncated = compress_messages(req["messages"], GEMMA_MAX_INPUT_TOKENS)
+                            if len(truncated) < len(req["messages"]):
+                                req["messages"] = truncated
+                                compressed_body = json.dumps(req).encode()
+                                log(f"truncate compress {model}: {orig_n}->{len(truncated)} msgs")
+                except (ValueError, TypeError, json.JSONDecodeError) as e:
+                    log(f"compression skipped (parse error): {e}")
+
+            return self._proxy_to(target, "POST", compressed_body)
+
+        # ── Anything else: forward to default backend ──
+        body = self._read_body()
+        for b in BACKENDS:
+            if fetch_models(b) is not None:
+                return self._proxy_to(b, "POST" if body else "GET", body)
+        self._json_response(502, {"error": "no backend up"})
+
+    def log_message(self, fmt, *args):
+        return
+
+
+if __name__ == "__main__":
+    log(f"boltzmann-llm-proxy v3 on :{LISTEN_PORT}")
+    log(f"  classifier: {CLASSIFIER_URL}")
+    log(f"  backends: {', '.join(n for n, h, p in BACKENDS)}")
+    http.server.ThreadingHTTPServer(("0.0.0.0", LISTEN_PORT), Handler).serve_forever()
diff --git a/start-proxy.sh b/start-proxy.sh
new file mode 100755
index 0000000..5652061
--- /dev/null
+++ b/start-proxy.sh
@@ -0,0 +1,6 @@
+#!/bin/bash
+pkill -f llm-proxy.py 2>/dev/null
+sleep 1
+cd /home/mfritsche/npu
+nohup python3 llm-proxy.py > proxy.log 2>&1 &
+echo "proxy started PID $!"
diff --git a/start.sh b/start.sh
new file mode 100755
index 0000000..49c5034
--- /dev/null
+++ b/start.sh
@@ -0,0 +1,6 @@
+#!/bin/bash
+pkill -f llamafile 2>/dev/null
+sleep 1
+cd /home/mfritsche/npu
+nohup ./llamafile --server -m qwen2.5-coder-1.5b-q4_k_m.gguf -c 32768 -t 4 --host 0.0.0.0 --port 8081 > llamafile.log 2>&1 &
+echo started PID $!