Lets Build a Serverless Function with Kiro

Lets Build a Serverless Function with Kiro

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  © Fujitsu 2025 1© Fujitsu 2025 1 Let's Build a Serverless Function with Kiro Chris Bingham AWS Ambassador & CTO Switzerland AWS User Group Zürich 24.11.25
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  © Fujitsu 2025 2 WARNING:Interactive Content Ahead! This is an interactive, collaborative session. We’ll attempt to build and deploy a serverless solution together using Kiro. Which is very much an experiment!
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  © Fujitsu 2025 3 ImprotantNote: Everything we do today will be with: ●Claude Sonnet 4.5 ●Spec Mode ●Autopilot
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  © Fujitsu 2025 4 SolutionStarting Point An S3 bucket, which image files get uploaded to. How could we process those images? Ideas time! + =
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  © Fujitsu 2025 6 PromptEngineering
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  © Fujitsu 2025 7 TopTips for Effective Prompting ●Based on my experience so far… ●Best practices could change with the next model version ●Top Tips: 1. Avoid ambiguity – be clear & specific 2. Include both context and constraints 3. Empasise the MUST and MUST NOT with block caps 4. Format with Markdown 5. Draft your prompt outside the chat box Prompt writing time!
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  © Fujitsu 2025 9 SteeringDocs
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  © Fujitsu 2025 10 Whatare Steering Docs? ●Provide cross-session solution consistency ●Specific to each solution ●Formatted with Markdown ●Yep, that’s a theme! ●Define: ●Your vision for the solution ●Purposes ●Goals ●Audience ●Constraints ●General guardrails for the decisions and actions the AI will take
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  © Fujitsu 2025 11 SteeringDoc Structure ●Could be organised in any way ●Defaults to three documents: ●product.md ●Describes the product we’re trying to build with Kiro ●Purpose, audience, business constraints ●structure.md ●Describes the code & repository structure and conventions ●Design principles for the solution ●tech.md ●Describes specific technical decisions the solution must adhere to ●E.g. tooling to use, AWS services to use/avoid, templates for specific build commands, etc.
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  © Fujitsu 2025 12 RequirementsDoc
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  © Fujitsu 2025 13 What’sthe Requirements Doc? ●Describe the intended outcomes ●In business terms, -ish ●Typically contains: ●General description of the solution ●Glossary of key terms ●Another mechanism to add consistency across sessions ●Numbered requirements ●User story ●Testable acceptance criteria
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  © Fujitsu 2025 14 Let’slook at our requirements doc!
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  © Fujitsu 2025 15 DesignDoc
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  © Fujitsu 2025 16 What’sthe Design Doc? ●Contents is highly solution dependant… duh! ●Typically describes ●Listing of key design decisions ●High-level architecture of the solution ●Description of each component in the architecture ●Description of how errors will be handled by the solution ●Strategy for testing the solution
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  © Fujitsu 2025 17 Let’slook at our design doc!
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  © Fujitsu 2025 18 TasksList
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  © Fujitsu 2025 19 What’sthe Task List ●Does exactly what it says on the tin! ●Breaks down implementation of the design ●Number tasks and sub tasks ●Each referencing the requirements it’s linked to ●Each with a “Start Task” option ●Each task is executed in a separate session (context window) ●Actively manages the scope of information fed to the model ●Which improves the quality of results ●By focusing the model on narrow, clearly defined goals
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  © Fujitsu 2025 20 Let’slook at our task list!
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  © Fujitsu 2025 21 Deploymenttime?
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  © Fujitsu 2025 22© Fujitsu 2025 22 Q&A Slides here >
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  © Fujitsu 2025 23© Fujitsu 2025 23 Thank you