This episode introduces CNCF Project DALEC, a declarative build tool designed to simplify how developers build, secure, package, and distribute containerized applications.

Traditional container builds often rely on complex Dockerfiles and custom scripting, which can create friction in developer workflows and reduce reproducibility across environments. DALEC approaches this problem differently by allowing developers to define builds using a declarative specification, making builds easier to reason about, maintain, and share across teams.

In this episode, we will explore:
1) The motivation behind DALEC and the problems it aims to solve in modern development workflows
2) How declarative container builds can improve consistency, security, and maintainability
3) A walkthrough of the DALEC developer experience, showing how developers can quickly define and build artefacts

Chapters:
00:12 Introduction
00:30 What is Project DALEC
01:15 How DALEC is different from traditional Dockerfile
03:25 Where DALEC fits in a broader supply chain - DEMO
07:11 How to get started with DALEC
09:20 DALEC Documentation
10:20 What's Next
11:15 How to Contribute

Resources:
GitHub Project: https://github.com/project-dalec/dalec
Documentation: https://project-dalec.github.io/dalec/

📌 Let's connect:
Tatsat Mishra | https://www.linkedin.com/in/tatsat-mishra-2390b45/
Brian Golf | https://www.linkedin.com/in/brian-goff-28a65b13/


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Microsoft Developer

DALEC (Dalek) is a declarative build tool that runs on top of BuildKit and serves as an alternative to Dockerfiles. Unlike the imperative layer-by-layer approach of Dockerfiles, DALEC uses a YAML spec file to declare inputs, dependencies, and outputs, letting the tool handle caching, dependency prefetching, and network isolation automatically. It integrates with the system package ecosystem to produce RPMs, Debian packages, and minimal containers. A demo shows building a Go binary into both Debian and RPM packages from a single spec file. DALEC also provides a VS Code extension with LSP support, code lenses, and debugger integration. The project is open source on GitHub, supports Mac/Linux/Windows, and aims to expand beyond containers to support any artifact type within the CNCF ecosystem.

DALEC Developer Experience: Declarative Builds and IDE Integration