notes on software design and engineering

notes on software design

• TODO

reference

• aosa
• Software Design by Example with js
• Software Design by Example with python
• A Philosophy of Software Design, 2nd Edition

notes on software engineering

• 组织规划力 - 从 ideas 到 发布的过程

  • 规划 把事情做成的流程计划 - f(x)

  • 用“3”的概念 先掌握住大框架， 再对细节做螺旋状前进

  • 幕后制作过程花絮

    • 看规划过程，希望能学习它的制作方法

  • 可以看到整体，也知道自己处在什么阶段

    • 可以看到前景，做事也有动力
    • 对于大规划中属于同性质的作业持续做就可以了
    • 或者学生相信这个教练的规划，就会全力努力

  • 自上而下思考，自下而上做

    • 自上而下的目标定位， 自下而上的改进

project thinking

• 工程化的思维

  • 想法

    • 识别问题
    • 头脑风暴，收集想法

  • 概念

    • 现有解决方案的需求
    • 约束条件

  • 计划

    • 定义目标， 制定时间计划表

  • 设计

    • 模型，算法，概念驗證
    • 根据头脑风暴的结果，来确定最终设计

  • 開發

    • 构建和测试

  • 发布

    • 展示结果

  • inception of idea 1-2

    • 想法 : 识别问题 - 清晰地定义问题, 研究其可行性, 检查是否有可行方案

  • proof of concept 3-6

    • 概念 - 提出概念性解决方案, 可能有多个方案,最终确定一个
    • 可行性计划 - 如何实施, 人员,任务,时间, 预算

  • production of samples/prototypes/tools 7-8

    • 设计 - 将解决方案细化, 设计架构和划分功能模块

  • conduct of trial schemes 9-10

    • 开发 - 根据设计方案, 实施构建, 并迭代

  • use in public sector/launch into open market

    • 发布

• 软件工程 = 过程 + 方法 + 工具

• 瀑布模型- 有序可控

  • 需求分析
    • 了解老板的想法 + 调研 + 设计原型
    • 让老板给反馈, 写产品设计文档, 划分不同模块
  • 軟件設計
    • 根據產品設計文檔, 把整体架构确定, 写技术方案
    • 开会讨论, 确认整体技术方案, 按照功能模块拆分

  • 程序編碼

  • 軟件測試

• 原型开发, 增量模型(模块化小瀑布), 迭代模型

• 敏捷开发

  • scrum(过程管理) + 极限编程(工程实践) + 看板(可视化)
  • 用户故事，理解用户需求
  • 在迭代中采用渐进式的架构设计； sprint 只做适合当前需求的架构设计
  • 定期重构解决技术债务
  • 功能开发的同时编写自动测试代码
  • 自动化持续构建

• 分而治之的策略

  • 拆分 + 流程

项目规划篇

TODO

a minimalistic mindset

• focus

  • focus on the vital few and ignore the trivial many

    • on the tasks that matter

  • 80/20

    • 20% delivers 80% of the results
    • Find what works. Do less of what doesn't

• keep it simple

  • apply simplicity in design
  • less is more

• MVP - a minimal viable product

  • focus on one hypothesis at a time about your user's needs
    • spend more time thinking about what features to implement than actually implementing them
  • release your MVP quickly and often
    • max the rate of progress toward product-market fit

• doing one thing well

• less is more in Design

System Design and Software Engineering

• TODO

• reference

  • building Systems
  • Software Architecture is Overrated, Clear and Simple Design is Underrated
  • Software Design
  • Engineering Software as a Service by Armando Fox / David Patterson
  • Shape Up by Ryan Singer
  • The Mythical Man Month

agile

• While I don't believe there is a one-size-fits-all development process I am a fan of some aspects agile development practices and the lean startup movement (especially as it applies to software process) - but am always eager to try new models and methods.

• reference

500L

• TODO

• reference

  • System Design Interview An Insider’s Guide
  • How to Solve It by G. Polya

Notes on soft-skills

• tell the hard from the impossible

  • Find a solution which is merely hard when it can be confidently scheduled and the risks are understood
  • make the requirement more clear
  • a clear definition of success - often become merely hards

• fight schedule pressure -> time-to-market pressure - reflect a financial reality

  • visible between the available labor and the product
  • maintain a concise and up-to-date project plan
    • mark progress
    • help make decisionss
  • how to estimate time
    • restate your assumptions
    • consider prototyping the task firstly
    • prepare a written estimate by decomposing the task into progressively smaller subtasks (less than a day)
    • make this visible to the manager
    • try to have the people to estimate, and have team-wide consensus on estimate

• Understand the user

  • figure out what people really want
  • spend more time with users, understand them
    • propose it to user
    • test your ideas against them as much as you can

• Gather support for a project

  • a prototype
  • demo real value

notes on engineering

• Problem Solving

  • Before you go rushing out to learn to code, figure out what your problem actually is.
    • Do you even have a problem?
    • Can you explain it to others in a way they can understand?
    • Have you researched the problem, and its possible solutions, deeply?
    • Does coding solve that problem? Are you sure?

• System thinking

  • Think about systems and how they interoperate. Systems Thinking is more important than coding.
  • Know what artifacts your system makes and what's needed for it to run. Know what kinds of things its good at and what it's bad at - in a non-zealous and non-egotistical way.
  • Understanding the basic building blocks are important.

• mini-project

  • 别做大项目。 从小项目开始，而且永远不要期望它变大。如果这么想（指做大型软件），就会做过度设计，把它想象得过于重要。更坏的情况是，你可能会被自己想象中的艰难工作所吓倒。

  • 所以要从小处起步，着力考虑细节。 别去想大图景和好设计。如果项目没解决某些需求，多半就是被过度设计了

• Think about Abstractions

  • learn how to think and when to dig deeper
  • learn how to question how things work
  • learn that everything new and simple hides something large and complex -> we are all standing on the shoulders of giants

• 总是想用不同的算法解决同一个数据问题，然后比较不同算法的效能

  • 不同应用场景对于算法的新奇度要求不一样
  • 在工业界，比起算法新奇度，解决方案的 scalability 更重要：能不能用到几个 T 的数据上，能不能当天内出结果，需要每天更新所有信息还是仅仅当天数据

Product Manager

• it's having the insights that lead to new products

  • the best of those come from working on hard tech problems

  • bulit the use case first and the protocol second

    • customers don't care about the technology, they care about the user experience
    • choose the right tech architecture to solve a particular customer problem

  • focus on the users, take moonshots and have ambitious ideas

    • we talk to our users and try to understand why there are gaps.
    • being a new area, we are building things that never existed before

  • big & small goals take the same effort, why not go big?

• confident

  • "since this sytem is new, we may face some challenges. Nevertheless, we are confident that the challenges can be overcome."

• builder

  • I am a builder at heart
    • it gave me the power to build things and when you see what you build work in front of your eyes, it can be quite powerful.

• reference

  • Inspired by Marty Cagan

ch4 Empathize with Stakeholders - product manager

• Talk to the Right People - who

  • create a stakeholder Map - a network diagram

• Discover the Business Goals - why they care

  • who wants it and what they want
  • Record Business Goal Statements
    • subject + measurable outcome + Context (the need)
    • "(stakeholder) Mayor wanna (goal) reduce procurement costs by 30%, (context) to avoid making budget cuts to education or other essential services in an election year."

ch5 - Architecturally Significant Requirements (ASR)

• planning

  • problem definition from a user's point of view
    • a clear statement of the problem that the sytem is supposed to solve
    • understanding what you want to build

  • requirements prerequisite ensure that the user drives the system's functionality

    • how to specify requirements well
    • the requirements checklist

  • system Architecture

    • determine the conceptual integrity of the system
    • a architecture first needs an overview that describes the system in broadterm
    • the architecture should define the major buildign blocks in a program
    • the communication rules for each buildign block should be well defined

• Define the what, the requirements from architecture

• Capture Constraints as Simple Statements

  • like "Must build a browser-based web application, the context is to descreases concerns about software delivery and maintenance."

• Capture Quality Attributes as Scenarios

  • Quality Attributes Scenarios describe how the system is expected to operate within a certain environmental context

  • a quality attribute scenario communicates the intent of the requirement so anyone can understand it

    • like "performace - A user sees research results within 5 seconds when the system is at an average load of 2 searchs per second."
    • "Availability - A user's searches for open RFPs and receives a list of RFPs 99% of the time on average over the course of the year."

  • precise and measurable

• Influential Functional Requirements

Design in Construction

ch6 - choose an Architecture

• architects choose structures to promote quality attributes in the system

• accept the constraints

• explore Patterns to promote desired Quality Attributes

• find the functional requirements and ensure the architecture can achieve them

  • assign specific functional responsibilities to each element

ch7 - how to explore design concepts

• collect published patterns catalogs

• design exploration - how

  • survey the existing ones
  • give a presentation of the available ones
  • share a brief demo
  • recommend a technology that seemed reasonable

• decision

  • "how do the proposed solutions influence our top-quality attributes?"

ch8 - how to create models

• pick an appropriate pattern as meta-model

  • meta-model defines the concepts and the rules of how the concepts are applied

• add new concepts to the meta-model

  • start the process by asking a question

    • like "which components cost us the most if they are unavailable"

  • Name it

    • the name describe the element's responsibility but also its purpose
    • understanding what it does and why it exists

• Organize code to make patterns obvious

  • pair with diff teammates
  • it would be wise to explore our architecture options in a collaborative workshop
    • not everyone agrees with or understands the current architecture

ch9 - how to make design decisions

• plan and facilitate an architecture design studio

ch10 - how to visualize design ideas

reference

• 軟件工程之美
• [System Design interview An insider's guide]
• 许式伟的架构课
• 硅谷产品实战 36 讲
• AI 技术内参
• python 核心技术与实战
• HowToBeAProgrammer
• [极客时间-python]
• [星球-陈老师每日精华]
• 软件工程之美
• [梁宁产品思维 30 讲]
• Systems Thinking as important as ever for new coders
• Please Learn to Think about Abstractions
• 500lines
• [code complete]
• [from programmer to architect]
• 44 engineering management lessons
• Managing people
• My Emotions as a CEO
• A collection of inspiring resources related to engineering management and tech leadership
• Heuristics for effective management
• How to mentor software engineers
• A Day in the Life of an Engineering Manager
• engineering-manager-role-explained
• Getting Started with Agility: Essential Reading