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Top Software Architectural Styles. The method to download the high-resolution image is available at the end. In software development, architecture plays a crucial role in shaping the structure and behavior of software systems. It provides a blueprint for system design, detailing how components interact with each other to deliver specific functionality. They also offer solutions to common problems, saving time and effort and leading to more robust and maintainable systems. However, with the vast array of architectural styles and patterns available, it can take time to discern which approach best suits a particular project or system. Aims to shed light on these concepts, helping you make informed decisions in your architectural endeavors. To help you navigate the vast landscape of architectural styles and patterns, there is a cheat sheet that encapsulates all. This cheat sheet is a handy reference guide that you can use to quickly recall the main characteristics of each architectural style and pattern. – Subscribe to our newsletter to download the 𝐡𝐢𝐠𝐡 𝐫𝐞𝐬𝐨𝐥𝐮𝐭𝐢𝐨𝐧 𝐢𝐦𝐚𝐠𝐞. After signing up, find the download link on the success page: https://lnkd.in/gtxpGKSt   #systemdesign #coding #interviewtips  .

GET, POST, PUT... Common HTTP “verbs” in one figure.   1. HTTP GET  This retrieves a resource from the server. It is idempotent. Multiple identical requests return the same result.    2. HTTP PUT  This updates or Creates a resource. It is idempotent. Multiple identical requests will update the same resource.    3. HTTP POST  This is used to create new resources. It is not idempotent, making two identical POST will duplicate the resource creation.    4. HTTP DELETE  This is used to delete a resource. It is idempotent. Multiple identical requests will delete the same resource.    5. HTTP PATCH  The PATCH method applies partial modifications to a resource.    6. HTTP HEAD  The HEAD method asks for a response identical to a GET request but without the response body.    7. HTTP CONNECT  The CONNECT method establishes a tunnel to the server identified by the target resource.    8. HTTP OPTIONS  This describes the communication options for the target resource.    9. HTTP TRACE  This performs a message loop-back test along the path to the target resource.    Over to you: What other HTTP verbs have you used? -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social   #systemdesign #coding #interviewtips  .

How to Learn API Development? Learning how to develop APIs is an important skill for modern-day developers. Here’s a mind map of what all you need to learn about API development: 1 - API Fundamentals What is an API, types of API (REST, SOAP, GraphQL, gRPC, etc.), and API vs SDK. 2 - API Request/Response HTTP Methods, Response Codes, and Headers. 3 - Authentication and Security Authentication mechanisms (JWT, OAuth 2, API Keys, Basic Auth) and security strategies. 4 - API Design and Development RESTful API principles include stateless, resource-based URL, versioning, and pagination. Also, API documentation tools like OpenAPI, Postman, Swagger. 5 - API Testing Tools for testing APIs such as Postman, cURL, SoapUI, and so on. 6 - API Deployment and Integration Consuming APIs in different languages like JS, Python, and Java. Also, working with 3rd party APIs like the Google Maps API and the Stripe API. Learn about API Gateways like AWS, Kong, Apigee. Over to you: What else will you add to the list for learning API development? -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social #systemdesign #coding #interviewtips .

Top 12 Tips for API Security  .  .  - Use HTTPS  - Use OAuth2  - Use WebAuthn  - Use Leveled API Keys  - Authorization  - Rate Limiting  - API Versioning  - Whitelisting  - Check OWASP API Security Risks  - Use API Gateway  - Error Handling  - Input Validation -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social   #systemdesign #coding #interviewtips  .

Software Architect Knowledge Map Becoming a Software Architect is a journey where you are always learning. But there are some things you must definitely strive to know. 1 - Master a Programming Language Look to master 1-2 programming languages such as Java, Python, Golang, JavaScript, etc. 2 - Tools Build proficiency with key tools such as GitHub, Jenkins, Jira, ELK, Sonar, etc. 3 - Design Principles Learn about important design principles such as OOPS, Clean Code, TDD, DDD, CAP Theorem, MVC Pattern, ACID, and GOF. 4 - Architectural Principles Become proficient in multiple architectural patterns such as Microservices, Publish-Subscribe, Layered, Event-Driven, Client-Server, Hexagonal, etc. 5 - Platform Knowledge Get to know about several platforms such as containers, orchestration, cloud, serverless, CDN, API Gateways, Distributed Systems, and CI/CD 6 - Data Analytics Build a solid knowledge of data and analytics components like SQL and NoSQL databases, data streaming solutions with Kafka, object storage, data migration, OLAP, and so on. 7 - Networking and Security Learn about networking and security concepts such as DNS, TCP, TLS, HTTPS, Encryption, JWT, OAuth, and Credential Management. 8 - Supporting Skills Apart from technical, software architects also need several supporting skills such as decision-making, technology knowledge, stakeholder management, communication, estimation, leadership, etc. Over to you - What else would you add to the roadmap? -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social #systemdesign #coding #interviewtips .

How does Docker Work?   Docker's architecture comprises three main components:    🔹 Docker Client  This is the interface through which users interact. It communicates with the Docker daemon.    🔹 Docker Host  Here, the Docker daemon listens for Docker API requests and manages various Docker objects, including images, containers, networks, and volumes.    🔹 Docker Registry  This is where Docker images are stored. Docker Hub, for instance, is a widely-used public registry. -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social   #systemdesign #coding #interviewtips  .

8 Key Data Structures That Power Modern Databases 🔹Skiplist: a common in-memory index type. Used in Redis 🔹Hash index: a very common implementation of the “Map” data structure (or “Collection”) 🔹SSTable: immutable on-disk “Map” implementation 🔹LSM tree: Skiplist + SSTable. High write throughput 🔹B-tree: disk-based solution. Consistent read/write performance 🔹Inverted index: used for document indexing. Used in Lucene 🔹Suffix tree: for string pattern search 🔹R-tree: multi-dimension search, such as finding the nearest neighbor Over to you: did we miss anything? -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social   #systemdesign #coding #interviewtips  .

The Data Engineering Roadmap Data engineering has become the backbone of effective data analysis. It involves managing, processing, and optimizing data to derive actionable insights. Here’s a roadmap that can help you get better at data engineering: 1 - Programming Languages Learn SQL and a few programming languages like Python, Java, and Scala. 2 - Processing Techniques Learn batch processing tools like Spark and Hadoop and stream processing tools like Flink and Kafka. 3 - Databases Focus on both relational and non-relational databases. Some examples are MySQL, Postgres, MongoDB, Cassandra, and Redis. 4 - Messaging Platforms Master the use of platforms like Kafka, RabbitMQ, and Pulsar. 5 - Data Lakes and Warehouses Learn about various data lake and warehousing solutions such as Snowflake, Hive, S3, Redshift, and Clickhouse. Also, learn about Normalization, Denormalization, and OLTP vs OLAP. 6 - Cloud Computing Platforms Master the use of cloud platforms like AWS, Azure, Docker, and K8S 7 - Storage Systems Learn about the key storage systems like S3, Azure Data Lake, and HDFS 8 - Orchestration Tools Learn about orchestration tools like Airflow, Jenkins, and Luigi 9 - Automation and Deployments Learn automation tools such as Jenkins, Github Actions, and Terraform. 10 - Frontend and Dashboarding Master the use of tools like Jupyter Notebooks, PowerBI, Tableau, and Plotty Over to you: What else will you add to the Data Engineering Roadmap? -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social #systemdesign #coding #interviewtips .

Top AI Coding Tools for Developers You Can Use in 2025 1 - AI Code Assistants GitHub Copilot: Code completion and automatic programming tool. ChatGPT: Helps write and debug code with the latest models. Claude: Recent and specialized coding knowledge to generate accurate and up-to-date code. Amazon CodeWhisperer: AI Assistant in the IDE 2 - AI-Powered IDEs Cursor: AI-powered IDE for Windows, macOS, and Linux. Windsurf: AI-powered IDE that tackles complex tasks independently. Replit: Create fully working apps to go live fast. 3 - Team Productivity Cody: The enterprise AI code assistant for writing, fixing, and maintaining code. Pieces: AI-enabled productivity tool to help developers manage code snippets. Visual Copilot: Convert Figma designs into React, Vue, Svelte, Angular, or HTML code. 4 - Code Quality and Completion Snyk: Real-time vulnerability scanning of human and AI-generated code. Tabnine: A code completion tool to accelerate software development. Over to you: Which other AI Coding Tool will you add to the list? What’s your favorite? -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social #systemdesign #coding #interviewtips .

How Netflix Built a Distributed Counter? A Distributed Counter is a system where the responsibility of counting events is spread across multiple servers or nodes in a network. Netflix needs to track and measure multiple user interactions to make real-time decisions and optimize its infrastructure. For this reason, they built a Distributed Counter Abstraction. Netflix’s Distributed Counter Abstraction operates in four main layers, ensuring high performance, scalability, and eventual consistency. 1 - Client API Layer Users interact with the system by sending AddCount, GetCount, or ClearCount requests. The Netflix Data Gateway efficiently processes and routes these requests. 2 - Event Logging and TimeSeries Storage Events are stored in Netflix TimeSeries Abstraction for scalability. Each event is tagged with an Event ID to ensure idempotency. To avoid database contention, events are grouped into time partitions known as buckets. Data is stored in Cassandra. 3 - Rollup Pipeline or Aggregation Rollup Queues collect event changes and process them in batches. Aggregation occurs in immutable time windows, ensuring accurate rollup calculations. Data is stored in the Cassandra Rollup Store for eventual consistency. 4 - Read Optimization (Cache & Query Handling) Aggregated counter values are cached in EVCache for ultra-fast reads. If a cache value is stale, a background rollup refresh updates it. This model allows Netflix to process 75K requests per second with single-digit millisecond latency. Reference: netflixtechblog. com/netflixs-distributed-counter-abstraction-8d0c45eb66b2 -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social #systemdesign #coding #interviewtips .

18 Key Design Patterns Every Developer Should Know Patterns are reusable solutions to common design problems, resulting in a smoother, more efficient development process. They serve as blueprints for building better software structures. These are some of the most popular patterns: - Abstract Factory: Family Creator - Makes groups of related items. - Builder: Lego Master - Builds objects step by step, keeping creation and appearance - Prototype: Clone Maker - Creates copies of fully prepared examples. - Singleton: One and Only - A special class with just one instance. - Adapter: Universal Plug - Connects things with different interfaces. - Bridge: Function Connector - Links how an object works to what it does. - Composite: Tree Builder - Forms tree-like structures of simple and complex parts. - Decorator: Customizer - Adds features to objects without changing their core. - Facade: One-Stop-Shop - Represents a whole system with a single, simplified interface. - Flyweight: Space Saver - Shares small, reusable items efficiently. - Proxy: Stand-In Actor - Represents another object, controlling access or actions. - Chain of Responsibility: Request Relay - Passes a request through a chain of objects until handled. - Command: Task Wrapper - Turns a request into an object, ready for action. - Iterator: Collection Explorer - Accesses elements in a collection one by one. - Mediator: Communication Hub - Simplifies interactions between different classes. - Memento: Time Capsule - Captures and restores an object's state. - Observer: News Broadcaster - Notifies classes about changes in other objects. - Visitor: Skillful Guest - Adds new operations to a class without altering it. -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social #systemdesign #coding #interviewtips .

A Simplified Git Workflow Learning Git is one of the fundamental skills for every developer out there. Here are the steps within a simple and basic Git workflow. 1 - Developer’s Working Directory (Untracked) to Staging Area (Index) The command for the same is “git add”. The files go from untracked to staged. 2 - Staging Area to Local Repository (Head) The command for this move is “git commit -m “message””. It saves changes to the local repository (HEAD), marking a version history. 3 - Local Repository to Remote Repository (Remote) The command for this move is “git push”. It uploads the committed changes to the remote repository (such as on GitHub) for collaboration. 4 - Remote Repository to Local Repository The commands “git pull” and “git fetch” help with this. “git pull” updates local files with remote changes. On the other hand, “git fetch” retrieves remote changes but does not merge them. The command “git merge” combines changes from different branches. 5 - Checking the Differences The command “git diff HEAD” shows the differences between the developer's working directory and the latest commit. Over to you: Which other step do you follow in your Git workflow? -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social #systemdesign #coding #interviewtips .

What is a deadlock? A deadlock occurs when two or more transactions are waiting for each other to release locks on resources they need to continue processing. This results in a situation where neither transaction can proceed, and they end up waiting indefinitely.    🔹 Coffman Conditions  The Coffman conditions, named after Edward G. Coffman, Jr., who first outlined them in 1971, describe four necessary conditions that must be present simultaneously for a deadlock to occur:    - Mutual Exclusion  - Hold and Wait  - No Preemption  - Circular Wait    🔹 Deadlock Prevention  - Resource ordering: impose a total ordering of all resource types, and require that each process requests resources in a strictly increasing order.    - Timeouts: A process that holds resources for too long can be rolled back.    - Banker’s Algorithm: A deadlock avoidance algorithm that simulates the allocation of resources to processes and helps in deciding whether it is safe to grant a resource request based on the future availability of resources, thus avoiding unsafe states.    🔹 Deadlock Recovery  - Selecting a victim: Most modern Database Management Systems (DBMS) and Operating Systems implement sophisticated algorithms for detecting deadlocks and selecting victims, often allowing customization of the victim selection criteria via configuration settings. The selection can be based on resource utilization, transaction priority, cost of rollback etc.    - Rollback: The database may roll back the entire transaction or just enough of it to break the deadlock. Rolled-back transactions can be restarted automatically by the database management system.    Over to you: have you solved any tricky deadlock issues? -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social   #systemdesign #coding #interviewtips  .

Virtualization vs Containerization Virtualization creates multiple VMs on a single physical server, each with its operating system, using a hypervisor. Containerization is a lightweight virtualization method that runs applications in isolated environments (containers) sharing the same operating system. Let’s look at the different possibilities in more detail. 1 - Bare Metal: Applications run directly on the operating system. No virtualization or containerization is used. It provides high performance but lacks flexibility. 2 - Virtualized: Uses a hypervisor to create VMs. Each VM has its guest OS, making it heavier on resources. Provides strong isolation but adds overhead. 3 - Containerized: Uses a container engine instead of a hypervisor. Containers share the host operating system, making them lightweight and efficient. It is faster and more scalable than VMs. 4 - Containerized on Virtualized: Runs containers inside VMs. Provides both flexibility and isolation, common in hybrid cloud environments. It balances resource efficiency with security. Over to you: Have you used VMs and Containers to deploy workloads? -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social   #systemdesign #coding #interviewtips  .

Top 5 Kafka use cases Kafka was originally built for massive log processing. It retains messages until expiration and lets consumers pull messages at their own pace. Let’s review the popular Kafka use cases. - Log processing and analysis - Data streaming in recommendations - System monitoring and alerting - CDC (Change data capture) - System migration Over to you: Do you have any other Kafka use cases to share? -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social   #systemdesign #coding #interviewtips  .

A handy cheat sheet for the most popular cloud services. Link to the high resolution at the end.   What’s included?  - AWS, Azure, Google Cloud, Oracle Cloud - Cloud servers  - Databases  - Message queues and streaming platforms  - Load balancing, DNS routing software  - Security  - Monitoring    Over to you - which company is the best at naming things? –  Subscribe to our newsletter to download the 𝐡𝐢𝐠𝐡-𝐫𝐞𝐬𝐨𝐥𝐮𝐭𝐢𝐨𝐧 𝐜𝐡𝐞𝐚𝐭 𝐬𝐡𝐞𝐞𝐭. After signing up, find the download link on the success page: https://bit.ly/3tiMC1B   #systemdesign #coding #interviewtips  .

Must-Know Network Protocol Dependencies Understanding network protocol dependencies is essential for cybersecurity and networking. Here’s a quick understanding of the same: 1 - IPv4 and IPv6 are the foundation of all networking. ICMP and ICMPv6 handle diagnostics, while IPsec ensures secure communication. 2 - TCP and UDP support various protocols. SCTP and DCCP serve specific cases. 3 - Some TCP-based protocols are HTTP, SSH, BGP, RDP, IMAP, SMTP, POP, etc. 4 - UDP-based protocols are DNS, DHCP, SIP, RTP, NTP, etc. 5 - SSL/TLS encrypts HTTPS, IMAPS, and SMTPS. 6 - LDAP and LDAPs are used for directory services over TCP and secured with SSL/TLS. 7 - QUIC is a UDP-based replacement for TCP+TLS for faster, encrypted connections. 8 - MCP or Model Context Protocol is an emerging standard for communicating with LLMs. Over to you: Which other network protocol will you add to the list? -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social   #systemdesign #coding #interviewtips  .

Explaining 9 types of API testing.    🔹 Smoke Testing  This is done after API development is complete. Simply validate if the APIs are working and nothing breaks.    🔹 Functional Testing  This creates a test plan based on the functional requirements and compares the results with the expected results.    🔹 Integration Testing  This test combines several API calls to perform end-to-end tests. The intra-service communications and data transmissions are tested.    🔹 Regression Testing  This test ensures that bug fixes or new features shouldn’t break the existing behaviors of APIs.    🔹 Load Testing  This tests applications’ performance by simulating different loads. Then we can calculate the capacity of the application.    🔹 Stress Testing  We deliberately create high loads to the APIs and test if the APIs are able to function normally.    🔹 Security Testing  This tests the APIs against all possible external threats.    🔹 UI Testing  This tests the UI interactions with the APIs to make sure the data can be displayed properly.    🔹 Fuzz Testing  This injects invalid or unexpected input data into the API and tries to crash the API. In this way, it identifies the API vulnerabilities. -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social   #systemdesign #coding #interviewtips  .

Design Patterns Cheat Sheet   The cheat sheet briefly explains each pattern and how to use it.    What's included?  - Factory  - Builder  - Prototype  - Singleton  - Chain of Responsibility  - And many more!    –  Like this post and subscribe to our newsletter to receive both part 1 and part 2 of the cheat sheet link: https://lnkd.in/eeGDwh88   #systemdesign #coding #interviewtips  .

How to Learn Backend Development? Backend Development requires knowledge of multiple aspects. Here’s a mind map of what all things a developer should learn: 1 - Fundamentals This includes topics like backend vs frontend, client-server, DNS, etc. 2 - Backend Programming Languages Choose between one or more programming languages like Java, Python, JS, Go, Rust, and C#. 3 - Databases This includes topics like types of databases such as SQL (Postgres, MySQL, SQLite), NoSQL (MongoDB, Firebase, DynamoDB), NewSQL (CockroachDB, Spanner). Other topics include working with ORMs and Database Caching. 4 - APIs and Web Services Learn about API types (REST, GraphQL, gRPC, SOAP) and authentication techniques (like JWT, OAuth 2, API keys). 5 - Server and Hosting This involves topics like backend hosting services (AWS, Azure, GCP), Containerization using Docker & Kubernetes, and Server Setup for Nginx, Apache, etc. 6 - DevOps Learn about CI/CD Pipelines using GitHub Actions and Jenkins, IaC (Terraform, Ansible) and Monitoring with tools like Prometheus, Grafana, ELK. Over to you: What else will you add to the list for learning backend development? -- Subscribe to our weekly newsletter to get a Free System Design PDF (158 pages): https://bit.ly/bbg-social #systemdesign #coding #interviewtips .