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Top 10 Concepts That Every Software Engineer Should Know
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The future of software development is about good craftsmen. With infrastructure like Amazon Web Services and an abundance of basic libraries, it no longer takes a village to build a good piece of software.
These days, a couple of engineers who know what they are doing can deliver complete systems. In this post, we discuss the top 10 concepts software engineers should know to achieve that.
1,587diggsdiggA successful software engineer knows and uses design patterns, actively refactors code, writes unit tests and religiously seeks simplicity. Beyond the basic methods, there are concepts that good software engineers know about. These transcend programming languages and projects - they are not design patterns, but rather broad areas that you need to be familiar with. The top 10 concepts are
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- Interfaces
- Conventions and Templates
- Layering
- Algorithmic Complexity
- Hashing
- Caching
- Concurrency
- Cloud Computing
- Security
- Relational Databases
10. Relational Databases
Relational Databases have recently been getting a bad name because they cannot scale well to support massive web services. Yet this was one of the most fundamental achievements in computing that has carried us for two decades and will remain for a long time. Relational databases are excellent for order management systems, corporate databases and P&L data.At the core of the relational database is the concept of representing information in records. Each record is added to a table, which defines the type of information. The database offers a way to search the records using a query language, nowadays SQL. The database offers a way to correlate information from multiple tables.
The technique of data normalization is about correct ways of partitioning the data among tables to minimize data redundancy and maximize the speed of retrieval.
9. Security
With the rise of hacking and data sensitivity, the security is paramount. Security is a broad topic that includes authentication, authorization, and information transmission.Authentication is about verifying user identity. A typical website prompts for a password. The authentication typically happens over SSL (secure socket layer), a way to transmit encrypted information over HTTP. Authorization is about permissions and is important in corporate systems, particularly those that define workflows. The recently developed OAuth protocol helps web services to enable users to open access to their private information. This is how Flickr permits access to individual photos or data sets.
Another security area is network protection. This concerns operating systems, configuration and monitoring to thwart hackers. Not only network is vulnerable, any piece of software is. Firefox browser, marketed as the most secure, has to patch the code continuously. To write secure code for your system requires understanding specifics and potential problems.
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8. Cloud Computing
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5. Hashing
The idea behind hashing is fast access to data. If the data is stored sequentially, the time to find the item is proportional to the size of the list. For each elemen -
, a hash function calculates a number, which is used as an index into the table. Given a good hash function that uniformly spreads data along the table, the look-up time is constant. Perfecting hashing is difficult and to deal with that hashtable implementations support collision resolution.
Beyond the basic storage of data, hashes are also important in distributed systems. The so-called uniform hash is used to evenly allocate data among computers in a cloud database. A flavor of this technique is part of Google's indexing service; each URL is hashed to particular computer. Memcached similarly uses a hash function.
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Hash functions can be complex and sophisticated, but modern libraries have good defaults. The important thing is how hashes work and how to tune them for maximum performance benefit.
4. Algorithmic Complexity
There are just a handful of things engineers must know about algorithmic complexity. First is big O notation. If something takes O(n) it's linear in the size of data. O(n^2) is quadratic. Using this notation, you should know that search through a list is O(n) and binary search (through a sorted list) is log(n). And sorting of n items would take n*log(n) time.Your code should (almost) never have multiple nested loops (a loop inside a loop inside a loop). Most of the code written today should use Hashtables, simple lists and singly nested loops.
Due to abundance of excellent libraries, we are not as focused on efficiency these days. That's fine, as tuning can happen later on, after you get the design right.
Elegant algorithms and performance is something you shouldn't ignore. Writing compact and readable code helps ensure your algorithms are clean and simple
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3. Layering
Layering is probably the simplest way to discuss software architecture. It first got serious attention when John Lakos published his book about Large-scale C++ systems. Lakos argued that software consists of layers. The book introduced the concept of layering. The method is this. For each software component, count the number of other components it relies on. That is the metric of how complex the component is. Lakos contended a good software follows the shape of a pyramid; i.e., there's a progressive increase in the cummulative complexity of each component, but not in the immediate complexity. Put differently, a good software system consists of small, reusable building blocks, each carrying its own responsibility. In a good system, no cyclic dependencies between components are present and the whole system is a stack of layers of functionality, forming a pyramid.
Lakos's work was a precursor to many developments in software engineering, most notably Refactoring. The idea behind refactoring is continuously sculpting the software to ensure it'is structurally sound and flexible. Another major contribution was by Dr Robert Martin from Object Mentor, who wrote about dependecies and acyclic architectures
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Conclusion
Modern software engineering is sophisticated and powerful, with decades of experience, millions of lines of supporting code and unprecidented access to cloud computing. Today, just a couple of smart people can create software that previously required the efforts of dozens of people. But a good craftsman still needs to know what tools to use, when and why
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- Interfaces
- Conventions and Templates
- Layering
- Algorithmic Complexity
- Hashing
- Caching
- Concurrency
- Cloud Computing
- Security
- Relational Databases
The top 10 concepts are:
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he future of software development is about good craftsmen. With infrastructure like Amazon Web Services and an abundance of basic libraries, it no longer takes a village to build a good piece of software.
-
These days, a couple of engineers who know what they are doing can deliver complete systems. In this post, we discuss the top 10 concepts software engineers should know to achieve that.
-
A successful software engineer knows and uses design patterns, actively refactors code, writes unit tests and religiously seeks simplicity. Beyond the basic methods, there are concepts that good software engineers know about. These transcend programming languages and projects - they are not design patterns, but rather broad areas that you need to be familiar with
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28 Jul 08
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- Interfaces
- Conventions and Templates
- Layering
- Algorithmic Complexity
- Hashing
- Caching
- Concurrency
- Cloud Computing
- Security
- Relational Databases
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27 Jul 08
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26 Jul 08
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Conventions and Templates
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Layering
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Security
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25 Jul 08
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24 Jul 08
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Brent Sordyl# Interfaces
# Conventions and Templates
# Layering
# Algorithmic Complexity
# Hashing
# Caching
# Concurrency
# Cloud Computing
# Security
# Relational Databases -
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FirstN@me L@stN@meThe future of software development is about good craftsmen. With infrastructure like Amazon Web Services and an abundance of basic libraries, it no longer takes a village to ...
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23 Jul 08
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Chris Pollockes design patterns, actively refactors code, writes unit tests and religiously seeks sim
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Scott AshwellThe future of software development is about good craftsmen. With infrastructure like Amazon Web Services and an abundance of basic libraries, it no longer takes a village to build a good piece of software.
architecture books programming software development concepts design
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