Embedded Systems Software Engineering Jarosław Kuchta Embedded Systems Software Engineering Agile Programming GUT - INTEL 2015/16 Embedded Systems Software Engineering

Classic methods weaknesses Large overhead for documentation Concrete results are lately achieved It is difficult to specify requirements at the early project stage Developers loose a contact with the client for a long time User requirements meeting is not guaranteed GUT - INTEL 2015/16 Embedded Systems Software Engineering

Embedded Systems Software Engineering Agile programming Agile Manifesto Individuals and interactions over processes and tools Working software over comprehensive documentation Customer collaboration over contract negotiation Responding to change over following a plan GUT - INTEL 2015/16 Embedded Systems Software Engineering

12 principles behind Agile Manifesto (1) Our highest priority is to satisfy the customer through early and continuous delivery of valuable software. Welcome changing requirements, even late in development. Agile processes harness change for the customer's competitive advantage. Deliver working software frequently, from a couple of weeks to a couple of months, with a preference to the shorter timescale. Business people and developers must work together daily throughout the project. Build projects around motivated individuals. Give them the environment and support they need, and trust them to get the job done. The most efficient and effective method of conveying information to and within a development team is face-to-face conversation. GUT - INTEL 2015/16 Embedded Systems Software Engineering

12 principles behind Agile Manifesto (2) Working software is the primary measure of progress. Agile processes promote sustainable development. The sponsors, developers, and users should be able to maintain a constant pace indefinitely. Continuous attention to technical excellence and good design enhances agility. Simplicity--the art of maximizing the amount of work not done--is essential. The best architectures, requirements, and designs emerge from self-organizing teams. At regular intervals, the team reflects on how to become more effective, then tunes and adjusts its behavior accordingly. GUT - INTEL 2015/16 Embedded Systems Software Engineering

Embedded Systems Software Engineering Agile Methods XP Programming Scrum Feature Driven Development Test-Driven Development Lean Software Development Dynamic Systems Development Method GUT - INTEL 2015/16 Embedded Systems Software Engineering

Embedded Systems Software Engineering Software life cycle GUT - INTEL 2015/16 Embedded Systems Software Engineering

Extreme Programming Rules(1) Planning Write user stories Create release plan Plan short, frequent iterations Plan each iteration just before it starts Management Create open space for developers Ensure sustainable work pace Organize short meetings at the beginning of working day Measure project speed with implemented user stories Move people between various tasks in the project Tread schedule flexible Design Use simple solutions Select proper system metaphor (proper naming) Implement only simple solutions for selected problems Do not add too much functionality too early Reuse and refactor code GUT - INTEL 2015/16 Embedded Systems Software Engineering

Extreme Programming Rules(2) Coding A customer is always available Code must keep standards Write unit tests before function coding Pair-programming (two developers at one console) Setup dedicated machine for code integration Only one pair integrates code at each time Code ownership is collective Testing All code must be covered by tests All code must pass the tests After an iteration, code must past acceptance tests based on user stories If an acceptance test unveils an error, a new unit test must be written and all tests should be rerun GUT - INTEL 2015/16 Embedded Systems Software Engineering

Embedded Systems Software Engineering SCRUM Sprints - short iterations Only 2-4 weeks for one sprint Three roles: Product Owner Scrum Master Team (utterly self managing) Product Backlog Sprint Planning Sprint Backlog Short daily meetings (scrums) – 15 min Sprint Review "Scrum process" by Lakeworks Licensed under GFDL via Commons - https://commons.wikimedia.org/ wiki/File:Scrum_process.svg#/ media/File:Scrum_process.svg GUT - INTEL 2015/16 Embedded Systems Software Engineering

Testing in agile programming New or modified code cannot be placed in repository until it passes all the tests. Only under this condition effective team work is possible. Acceptance tests are designed basing on user stories. A user should describe test scenarios. One user story may have many acceptance tests. No user story is considered to be implemented until it passes all the acceptance tests. GUT - INTEL 2015/16 Embedded Systems Software Engineering

Agile programming characteristics Pros Cons Time effective (only development & testing) Easily fitted to requirements changes Can be used when requirements are unknown Process depends on people – risk of team change No possibility to return to the project after a long break - lack of documentation The possibility of serious design errors (e.g. special and emergency situations) High cost of changes during software usage GUT - INTEL 2015/16 Embedded Systems Software Engineering

Embedded Systems Software Engineering Conclusions Agile Programming is more effective than classic methodologies (e.g. RUP), Agile Programming can assure software quality under some key conditions. Agile Programming usage: Simple applications Low risk at project failure Continuous product maintenance GUT - INTEL 2015/16 Embedded Systems Software Engineering

Key conditions for quality Close cooperation (communication) with customers in the whole development time. Release objectives based on real customers’ needs. Keeping good engineering practices. Keeping a schedule of frequent releases (a continuous work in the same project) Reliable unit test writing and test passing before each release. Passing acceptance tests based on real usage scenarios. GUT - INTEL 2015/16 Embedded Systems Software Engineering

Embedded Systems Software Engineering Sources Kent Beck: Extreme Programming Explained: Embrace Change, Addison- Wesley, 1999 http://www.xprogramming.com http://www.extremeprogramming.org http://www.agile.com http://www.pairprogramming.com http://www.martinfowler.com http://www.xp123.com http://www.thoughtworks.com http://www.rolemodelsoftware.com http://www.industriallogic.com/xp http://www.agilealliance.org GUT - INTEL 2015/16 Embedded Systems Software Engineering