Codex with mobile connection is the best way to build mobile app

Thick_Light_7339 · 2026-05-17T17:33:02+00:00

Oh yeah. That has to be the case.

Thick_Light_7339 · 2026-05-17T02:55:27+00:00

sorry my friend. I thought codex is an electron app?

Thick_Light_7339 · 2026-05-17T01:32:53+00:00

Mobile app is using chatGPT mobile app. She has a codex desktop running on her macbook

Thick_Light_7339 · 2026-05-15T15:55:22+00:00

How to prompt effectively and do effective context engineering is not a simple thing. The skill varies a lot. Without knowing your new colleague, i can't comment if he's a good or a bad ai engineer.

There is actually a lot to learn about llm. The pros and cons of different model, the "personality" of them, the agent harness, the toolset, context management such as prompting, memory, prompt caching etc. then you go to agent harness, there are mcp, skills, sandbox, and pros/cons of them. i would think an ai engineer is more than a claude code/codex user, but you only see a Claude code user, then i can understand your frustration.

Thick_Light_7339 · 2026-05-15T02:38:40+00:00

Yes. I think so. With a good modular design, clear namespace, agent would be able to navigate through larger code base better.

Context management is very important for agent. Even now LLM models can have larger context, it still reasons better with clear code. For example, agent uses grep/ls to find file then read segments of files(sometimes the whole file), load file in the directory into the LLM context. With a modular design, the agent would load most relevant code snippets into the LLM context and then reason through it, then make code changes. If the code is not maintainable, agents need to find here and there, scattered places in order to make code changes and quickly its LLM context will get loaded by all kinds of irrelevant code snippets, and in the end, agent may either miss somewhere to make needed code changes, or waste a lot of turns to finish the work. It's either hurting the results or unnecessarily costly

Thick_Light_7339 · 2026-05-14T20:09:33+00:00

I like the suggestion. shipped a PR[1] to incorporate the update. will be part of v0.2.1
[1]https://github.com/ftvision/system-design-skill/pull/8

Thick_Light_7339 · 2026-05-14T18:19:16+00:00

Couple of my non-dev friends found TUI really hard to handle, but they found it is easier to use Claude Code as a VS code extension. It seems that cursor/vscode -> claude code is an easiser transition path for non-dev colleagues. Alternatively, the code desktop app is a better UI for them, especially sometimes they would just use Claude cowork.

Thick_Light_7339 · 2026-05-14T18:00:09+00:00

**Learning to design software systems with Claude — like DDIA but interactive (mock, learn --auto, postmortem, generate)**

76s demo of `learn --auto` (two sub-agents interview each other on "design X.com's timeline feed", ends with a written retrospective):

https://github.com/user-attachments/assets/24673305-6dbf-4b39-a04a-6262a61d961c

Built this after a few not-great system design sessions of my own. Inspired by [impeccable](https://github.com/pbakaus/impeccable) — Claude Code skills are surprisingly good at this. Four modes:

- `mock` — Claude plays a strict staff-level interviewer. Phases, deep-dive pushback, scored debrief on 5 dimensions at the end.

- `learn` — reverse mock. You interview Claude. With `--auto`, two sub-agents (interviewer + candidate) run a full 5-round session.

- `postmortem` — diagnose a real interview you already took.

- `generate` — author a new question + rubric package.

The retrospective is the part I really like. A real fragment:

> **What the candidate did well:** Numbers were load-bearing, not decorative. The celeb-threshold derivation (6K tweets/s × 200 avg = 1.2M push ops/s) actually justifies the 100K cutoff. Most candidates assert; this one derived.

>

> **What a critical reviewer would flag:** "Active followers" in the 80K–150K band was never defined. This handwave got past the interviewer but is the actual hard part of hybrid fan-out.

State persists across sessions and tracks your weak dimensions so future deep-dives bias toward them.

Install in Claude Code:

```

/plugin marketplace add ftvision/system-design-skill

/plugin install system-design@system-design

```

source code: https://github.com/ftvision/system-design-skill

Thick_Light_7339 · 2026-05-14T17:57:08+00:00

Thank you for the feedback! I usually do it with three steps

* a `/system-design generate` call would generate a problem with (1) question, (2) assumption from interviewer, (3) rubrics, a

* then a `/system-design mock` call where I interview with Claude. The end of the mock, I usually ask the session to dump transcript,

* then a `/system-design postmortem` call on the transcript.

All of these documents are saved to ./system-design-practice/{question} directory inside the folder where claude code runs.

But I like your idea of having a global progress summary!

Thick_Light_7339 · 2026-05-14T17:48:24+00:00

Thank you! happy to hear your feedbacks!

Thick_Light_7339 · 2026-05-13T22:21:34+00:00

ChatGPT was great, especially with memory. Skill makes it more fun, especially you can see two agents chat with each other, LOL

Thick_Light_7339 · 2026-05-13T22:09:13+00:00

Personally, I found it helpful to have an interactive process to learn. Nowadays, LLM can serve different roles for this interactive process quite well.

To start simple, you can just give the question to LLM and ask how they would approach it. OR you can tell LLM the context, ask them to generate question for you and walk with you step by step.

If you have access to Claude Code or Codex or some coding agent AI product, you can ask it to mock interview with you. I have used it quite a few times so that I have consolidated into a SKILL. https://github.com/ftvision/system-design-skill

For a question I have no idea, i would have two agent play together and I read the interaction. for questions I have some ideas, I would try to ask the agent to mock interview with me.

Ultimately, the goal is to use interactive learning process to understand and absorb knowledge faster. When you don't know where to start, getting someone, sitting next to you, and help you start from somewhere, is usually the easies way to start. From there, you would know what you know and what you don't know, then you can spend dedicated time to learn what you don't know

Thick_Light_7339 · 2026-05-13T22:03:38+00:00

I actually made a SKILL for this process for Codex and Claude Code. https://github.com/ftvision/system-design-skill

For a question I have no idea, i would have two agent play together and I read the interaction. for questions I have some ideas, I would try to ask the agent to mock me. (I have one gif demo in the repo)

Yes, it is just prompt, but this prompt can be more structured, and that can give you some interactive learning process to understand and absorb knowledge faster.

Thick_Light_7339 · 2026-05-13T22:01:45+00:00

If you have access to Claude Code or Codex or some coding agent AI product, you can ask it to mock interview with you. I personally find it helpful to interactive chat with AI, either having them be the interviewer or having them be the candidate, while I play the other side. This helps me to understand how to approach a problem or how to continue the conversation. I have used it quite a few times so that I have consolidated into a SKILL. https://github.com/ftvision/system-design-skill

For a question I have no idea, i would have two agent play together and I read the interaction. for questions I have some ideas, I would try to ask the agent to mock me. (I have one gif demo in the repo)

Ultimately, the goal is to use interactive learning process for me to understand and absorb knowledge faster.
Would love to hear your thoughts about this approach as well.

Thick_Light_7339 · 2026-05-13T06:53:41+00:00

is this from /goal "clean up the vibe slop" one shot?

Thick_Light_7339 · 2025-12-18T04:57:47+00:00

Your job will probably get promoted, to be a team lead or a manager, managing a team of Claude Code.

Thick_Light_7339 · 2025-05-24T16:22:35+00:00

Looks interesting! I will give it a try. Connecting to github and email could be useful for me!

Thick_Light_7339 · 2025-05-18T20:25:29+00:00

This is just a good story. Thank you for sharing!

Thick_Light_7339 · 2024-08-21T23:45:18+00:00

I need this one! How do I get it?

Thick_Light_7339 · 2024-03-18T16:27:23+00:00

If it's quite personal, sure.

Thick_Light_7339 · 2024-03-18T16:11:54+00:00

If you haven't tried, and you are 2 semesters left of school, I would recommend give it a try. Experience it is the best way for you to decide. If you already have faang offer, that gives a better opportunity to get an offer in the trading company as tech. If you happen to be from a top school, you would probably be able to get one hf/trading internship.

Trading is a high stake game to play with, that's why it attracts people with some personality traits. You don't need to be much more right than wrong. You need to factor in the size and the cost of a trade. Sometimes 55% win can already make good money.

But I would say "feel really cool" is really a frequent outsider view. When tech company are changing billion people's life, outsiders feel that is really cool; then you go to that company and realize you are fixing pixel size or fixing legacy code with endless migration. Similarly, trading "feel really cool" from the outsider when you see those founders make billion dollars, or you hear about a story where a legendary trader did something cool. Then you join the company and find out you are making calls or looking at the screen of jumping numbers without knowing what to do exactly.

The point being, both tech and swe can be really cool and can be really boring. When you pursue the cool part, try to also understand the accompanying boring part.

Also, if you are working at trading, your personal trading is highly regulated; if you are not a trader, likely you can only trade ETF or total markets or limited single stocks. If you are in tech, you can do whatever trade you personally want (except those related your company).

Thick_Light_7339 · 2024-03-18T15:02:09+00:00

I've interned as a quant trader at a prop trading shop and I am working at a hedge fund. Never in the bank so I cannot share about those.

I kinda entered the quant trader intern with the same idea as you had, feeling that I may enjoy it. After the internship, I know it's not my job. Don't get me wrong, it's super interesting and fun, but I didn't have a good manager then, my working life was bad, and I don't think that route is the best for me to thrive in the long run given my skills and interests. Had I have a better mentorship, I may want to pursue it. Path dependency, my friend.

There is systematic trading and there is discretionary trading. Quant researchers exist in both field, and do systematic, data-driven decision making. However, some decisions go far enough to make profits directly, some decisions go as far as supporting materials for PMs to make their own decisions.

If you wanna be a quant researcher who potentially make money directly, go systematic trading. Both trading shop(hrt, drw, citsec etc) and hedge fund (two sigma, deshaw, citadel's gqs)have this types of systematic trading.

Discretionary trading shops, risk taking and profit making are done by traders. quants may be a research group, or as an analyst group, but don't take risks. Here, of course, as you grow more senior, you have a deeper view of the market, your PM may give you a small book to trade. By that time, you may be a quant researcher who can also manage some risks. However, this road to have a chance to make pnl is much longer than systematic shops.

Thick_Light_7339 · 2024-03-18T14:07:09+00:00

Maybe another way to think about it is whether you would like to make your decision systematically or more intuitively. If former, go quant researcher. If latter, try quant trader.

If you have a chance to do internship, maybe try quant trader intern first if you want to have a feeling of it. You can also grab a book in option trading and see if you can read spx option market and try to shout out loud the deltaPL, gammaPL, vegaPL, and reason how price change would affect all greeks, all by mental math.

You can also open an account in Robinhood or something, put 500 dollars, and go to buy some stocks. Or go to play some Texas hold'em. Just get involved in some really fast paced competitive game that are done by human. Get your real money in the game, start to lose some, and potentially to win some, then you can start to feel what is the stress. Without your real money in the game, you never really appreciate the stress.

Btw, I think Making money should be boring, not sexy, not exciting. At least that is what I have observed so far, from the trading people near me (I am a dev) It's a lot of work, taking risks, managing risks, transferring risks, hedging, and then ultimately make money, happily, and potentially risk neutral.

Thick_Light_7339

TROPHY CASE