# Search log — Chinese freelance platforms for pneumatic wrist-prototype builds

**Date:** 2026-06-30
**Goal:** find Chinese freelancers / small studios with bench-prototyping experience in MCU + sensor + wearable/pump domains who could build a wrist-worn pneumatic prototype in 2–4 weeks.

## Platforms tried

| Platform | Status | Notes |
|---|---|---|
| DuckDuckGo | ❌ | bot-detection challenge; unusable |
| Google raw | ❌ | empty / consent gate; useless from this box |
| **Brave search** | ✅ | works on this box (per AGENTS.md); only reliable discovery channel |
| 程序员客栈 proginn.com | ✅ | **best signal** — has structured hardware-dev category with searchable keyword index, profile detail accessible without login |
| 猪八戒 zbj.com | ❌ | CloudWAF 502 / 404 from this egress IP; listings unreachable |
| 一品威客 task.epwk.com / epwk.com | ❌ | CloudWAF 502; unreachable from this box |
| 21ic project.21ic.com | ⚠️ | homepage loads but is a wall of banned-user notices; listings not surfaced |
| 闲鱼 / Xianyu | ❌ | Google returns only generic Goofish platform docs, not specific freelance listings |
| 实现网 / 码市 / 猿急送 / 智慧外包 | (not reached) | surfaced in Brave search snippets; landing pages not crawled from this box |

**Reality:** from the openclaw datacenter egress (178.105.110.42, hetzner falkenstein), the two biggest Chinese freelance platforms (zbj.com, epwk.com) are blocked at the WAF layer. Proginn.com is the **only platform where I could pull structured freelancer data + profile detail**. Brave search returned snippets referencing zbj/epwk listings, but I couldn't fetch the listings themselves to verify.

## Search queries run

Via Brave Search (best working engine) and proginn.com keyword search:

| Query (encoded) | Result count (proginn.com) | Top hits |
|---|---|---|
| `气泵` (air pump) | 1 | u/234652 "AssassinEzio" (Beijing, 10y) |
| `穿戴` (wearable) | 132 | mixed; mostly app/UI; some hardware |
| `穿戴设备 + 单片机` | 575 | wearable + MCU developers |
| `压力传感器` (pressure sensor) | 5 | wo/967636, wo/57135, wo/564891, … |
| `智能硬件开发` (smart-hardware dev) | 2405 | huge; filtered to hardware category |
| `手表 + 原型` (watch + prototype) | 22 | wo/583730 (BP watch!), wo/981981 (smartwatch), wo/1252273 (气压计手表), wo/1006699 (LVGL watch), wo/563678 (ESP32 watch) |
| `医疗器械` (medical device) | 637 | mixed |
| `医疗 + 嵌入式` (medical + embedded) | 637 | mostly software / app |
| `气压开关 + 单片机` | 499 | filtered to hardware category |
| `ESP32 + 原型 + 硬件` | 2405 | MCU hardware devs |
| `环境传感器 + 原型` (env sensor + prototype) | 179 | wo/81630 (laser sensor dev), wo/967636 (pressure), wo/1054791 (water leak), wo/911153 (sensor), wo/1132175 (force-feedback) |

## Strategy

1. Discover leads via proginn.com's **hardware-dev category page** (which surfaces freelancers with explicit hardware projects).
2. Filter by keyword searches ("气泵", "穿戴", "手表 + 原型", "压力传感器") to find people who've worked on **wrist / pressure / wearable** projects.
3. Pull each top profile and look for: explicit MCU + sensor + physical build evidence; Shenzhen/Dongguan/Hangzhou/Shanghai/Beijing location; years of experience; signs they can do a bench prototype (not just PCB schematic).
4. Score on the rubric: 10 = clear pump/wearable + bench-prototype track record; 7–8 = strong MCU + physical build; 5–6 = generic hardware dev.

## Leads found (12)

The strongest 12 candidates. CSV block at bottom; summary here:

| Rank | Lead | Location | Why relevant |
|---|---|---|---|
| ★10 | 硬件工程师吕工 (wo/990481) | 北京 10y+ | Built a small air-quality station with **pressure sensor + proportional valve + PID control + solenoid switching** — literally the same subsystem stack as our wrist device. |
| ★9 | high_time (wo/583730) | 深圳 10y+ | Built a **Nordic-MCU smart BP watch** — wrist form-factor, pressure-sensor-driven, same exact problem class. |
| ★9 | 天津单片机开发工作室 (wo/1143597) | 天津 7y | **Studio** (5-engineer team, 47 projects, 120k+ units shipped). Built medical sterilization box, industrial motor drivers, low-power (<1μA standby) STM32/ESP32. Full-stack hardware+firmware+production. |
| ★8 | 二次充能 (wo/1137317) | 重庆 | STM32+FreeRTOS+OTA end-to-end IoT prototype builds; sensor + cloud integration; master's in mech-electronics. |
| ★8 | _生姜_ (wo/967636) | 北京 10y+ | **Pressure sensor firmware specialist** — built "压力传感器固件", "水压致裂数据采集"; explicit pressure + MCU bench work. |
| ★8 | Troy_Linux (wo/981981) | 石家庄 5y | Built a **6-axis IMU + heart-rate LVGL smartwatch** with low-power wake-up; full bench prototype incl. OTA, charging, PCB. |
| ★7 | binbinbin (wo/563678) | 深圳 3y | ESP32 wearable work + **motor-speed-by-airflow** prototype (close to pneumatic control). ESP32 + 立创EDA schematic+PCB+assembly. |
| ★7 | 硬件瓜哥 (wo/1217052) | 深圳 10y+ | 4G定位器 + 蓝牙水表 (sensor + low-power + wireless + bench builds); 30y in hardware incl. mobile module production. |
| ★7 | Watson (wo/81630) | 深圳 6y | Sensor R&D director (光电传感); 激光位移传感 + proportional valve pressure control. |
| ★6 | minapp1547196686 (wo/1252273) | 广州 10y+ | **高度气压指南针计步手表** — explicit wrist-worn pressure-sensor watch. |
| ★6 | 嵌入式阿唐 (wo/1124973) | 漯河 2y | Built a 智能手表 prototype. Low experience → lower confidence. |
| ★5 | SoulHot (wo/1006699) | 深圳 2y | LVGL smartwatch + smart-home sensor hub; profile is thin. |

### Notable non-leads (excluded with reason)

- **u/234652 "AssassinEzio"** (Beijing, 10y, tagged "气泵" in proginn index) — **only** profile with explicit "air pump" keyword match. But profile requires login (the `/u/` path is gated), so detail unavailable from this box. Listed as speculative; would need direct contact via proginn chat to verify.
- **wo/1215421 (糖糖)** — explicit "STM/ESP/GD/STC MCU consumer hardware design + 0201/BGA soldering" — strong generalist, no specific wearable/pump track record shown. Good backup.
- **wo/1003167 (深圳 FAE)** — fitness/cycling/sport electronics, BLE, low-power; **strong wearable-adjacent** but profile doesn't mention bench-prototype for hire, more FAE-style.
- **wo/683022 (北京工匠生物科技)** — built 气溶胶监测 + 远程气溶胶采样 devices. Pneumatic-adjacent (sampling pumps) but works in product, not freelance.
- **wo/1057119 (北京, 8y, "智能及物联网软硬件")** — strong but no specific wearable/pump track record visible.
- **wo/1124973 (漯河, 2y)** — built a 智能手表, but 2 years exp & 漯河 location → risk of being out of his depth on a bench-prototype project.

## Caveats

- **Datacenter-IP gating**: openclaw egress (178.105.110.42, hetzner) is on a known datacenter range. Zbj.com, epwk.com, 21ic.com all returned 502/404 at the WAF layer. Real leads on those platforms would need a residential-IP browser or for ishmael to search and paste URLs back.
- **Proginn.com requires login for direct-contact chat** but profiles are public-readable (most fields). Some fields (e.g. education, contact phone) are gated to logged-in viewers.
- **"Willing to start from idea"**: can't be verified from profiles. All leads listed are freelancers/studios on a paid platform → assume they take paid work. Real willingness to do an idea-stage prototype requires DM ping.
- **No direct quote**: pricing shown is 月 salary-equivalent (10875元/月 ≈ 6500 RMB/day rate). Actual prototype quotes would need a separate RFP.
- **Two studios (天津工作室 + 硬件瓜哥)** vs individual freelancers — studios can absorb more scope; individuals are cheaper but capacity-limited.

## Recommendations (next steps for the user)

1. **First batch to contact** (highest fit, ~5 leads):
   - 硬件工程师吕工 (990481) — pressure + valve + PID
   - high_time (583730) — BP watch precedent
   - 天津单片机开发工作室 (1143597) — actual studio, medical-adjacent
   - _生姜_ (967636) — pressure sensor specialist
   - 二次充能 (1137317) — IoT prototype expert

2. **If none respond, expand to**: Troy_Linux, binbinbin, 硬件瓜哥, Watson, minapp1547196686.

3. **For a residential-IP / captcha-protected view of zbj.com and epwk.com listings**: ask ishmael to search those from his own machine.

4. **Verify willingness before paying**: ask each lead for (a) a 5-line description of their most relevant prior project, (b) confirmation they have a 3D printer / bench assembly setup, (c) their rate + earliest start.

---

## CSV block

```csv
score_1_to_10,lead_name,url,note,search_query_that_found_it
10,硬件工程师吕工 (wo/990481),"https://www.proginn.com/wo/990481","Built a 小型空气站 with STM32F469 + 气体流量控制 + 开关阀 + 压力传感器信号采集 + 比例阀控制 + PID恒流控制 — literally the pressure/valve/sensor/PID subsystem stack our wrist device needs. Beijing, 10y+ exp.","环境传感器 + 原型 (proginn.com)"
9,high_time (wo/583730),"https://www.proginn.com/wo/583730","Built a Nordic-MCU 智能血压手表 (smart BP watch): pulse-wave acquisition, dynamic waveform display, BP/HR analysis, cloud storage. Wrist form-factor + pressure sensor + low-power — exact prior art. Shenzhen, 10y+ exp.","穿戴设备 + 单片机 / 手表 + 原型 (proginn.com)"
9,天津单片机开发工作室 (wo/1143597),"https://www.proginn.com/wo/1143597","Studio (5-engineer team, 47 projects, 120k+ units shipped). STM32/ESP32/GD32 full-stack. Built 医疗消毒盒 + 工业步进电机驱动器 + 4G物联网数据采集卡 + 气体超声流量计 (EMC-IV certified). Low-power (<1μA standby). 天津, 7y+.","气压开关 + 单片机 (proginn.com)"
8,二次充能 (wo/1137317),"https://www.proginn.com/wo/1137317","Independent IoT developer; built STM32+FreeRTOS end-to-end prototype with OTA (A/B partitions + rollback), Tickless low-power, Modbus/MQTT, Huawei Cloud IoT. Master's in mech-electronics. Chongqing, 5y+.","穿戴 + 单片机 (proginn.com)"
8,_生姜_ (wo/967636),"https://www.proginn.com/wo/967636","Built 压力传感器固件 (24-bit AD, 100Hz, RS-485) + 水压致裂数据采集 + 高精度热敏电阻测试电路. Pressure-sensor specialist at bench-prototype scale. 中国地质科学院, 副高职称, 15y+.","压力传感器 (proginn.com)"
8,Troy_Linux (wo/981981),"https://www.proginn.com/wo/981981","Built a 6-axis-IMU LVGL smartwatch (计步/抬腕唤醒/心率/天气/指南针) + a solar-powered fingerprint smart lock with ultra-low-power + OTA. End-to-end bench prototype incl. PCB. Shijiazhuang, 5y.","穿戴设备 + 单片机 / 手表 + 原型 (proginn.com)"
7,binbinbin (wo/563678),"https://www.proginn.com/wo/563678","Built ESP32 smartwatch prototype + a motor-speed-by-airflow controller (立创EDA schematic+PCB+assembly+焊+调). Closest match to pneumatic-motor control. Shenzhen, 3y.","手表 + 原型 (proginn.com)"
7,硬件瓜哥 (wo/1217052),"https://www.proginn.com/wo/1217052","30y hardware exp. Built 4G定位器 + 蓝牙智能水表 (camera+MCU+BLE+4G, low-power). Senior at 广和通 (4G module) + TCL mobile. Shenzhen. Capable of full PCB→整机 build.","智能硬件开发 (proginn.com)"
7,Watson (wo/81630),"https://www.proginn.com/wo/81630","Sensor R&D director. Built laser displacement + TOF sensors with pressure/flow control.光电传感 + 比例阀 experience. Shenzhen, 12y+.","环境传感器 + 原型 (proginn.com)"
6,minapp1547196686 (wo/1252273),"https://www.proginn.com/wo/1252273","Built 高度气压指南针计步手表 (altitude/barometer/step watch) — wrist-worn + barometric pressure sensor. STM32/STC + LCD/OLED + 计步算法. Guangzhou, 10y+ freelance.","穿戴 + 单片机 (proginn.com)"
6,嵌入式阿唐 (wo/1124973),"https://www.proginn.com/wo/1124973","Built a 智能手表 prototype. Lower exp (2y) and inland location (漯河) → higher delivery risk; included as backup.","穿戴设备 + 单片机 / 手表 + 原型 (proginn.com)"
5,SoulHot (wo/1006699),"https://www.proginn.com/wo/1006699","LVGL smartwatch + smart-home sensor hub (温湿度/光照/空气质量 + 舵机门锁 + 人脸识别). Profile is thin (just '能干'); 2y exp. Speculative.","穿戴设备 + 单片机 (proginn.com)"
```

(Plus a speculative entry from the 1-result "气泵" search — could not verify detail from this box because the profile is gated behind login:)

```csv
score_1_to_10,lead_name,url,note,search_query_that_found_it
4,AssassinEzio (u/234652),"https://www.proginn.com/u/234652","Only profile in proginn.com's index with the keyword '气泵' (air pump). Beijing, 10y. Profile detail gated behind login; needs DM ping to confirm air-pump work. Listed speculatively.","气泵 (proginn.com)"
```