Senior Software Developer, AI Agents

Job summary

You will design and implement the core agent runtime in Python, including orchestration, tool execution, and memory management. Additionally, you will own agent evaluations by building automated pipelines to measure quality and drive improvements.

Job details

KNAK IS A MISSION-DRIVEN COMPANY Why? Because our time is limited, our competition is fierce, and our margin for error is small. To have the biggest impact on the world, we stay focused on our core mission, which is... Empowering marketers to be creative. That’s why Knak exists. In a world where AI has made everyone a creator, Knak helps marketers turn ideas into on-brand, high-performing campaigns at scale. The world's most AI-forward companies, including Meta, OpenAI, NVIDIA, Vercel, Notion and Stripe, use Knak as their agentic marketing production layer. Here's what they and our investor Insight Partners figured out: creation got easy, but that’s making production harder. Every new idea and brief still has to be built, versioned, checked, approved, and shipped across every channel, and that work runs on handoffs, review cycles, and a lot of copy-paste. That middle stretch of the marketing stack has no system, no standard, and no owner. Knak is the flexible factory for that work. Our customers set the brand rules, choose the tools that feed in and the platforms that send, and decide where AI does the work and where people do. We handle the repeatable parts, so marketers get their time back for the parts that aren't. We're built by marketers, for marketers. We started with email because it's the hardest channel to get right and where many campaigns win or lose. Now we're bringing that same production discipline to every channel our customers use. THE ROLE: SENIOR SOFTWARE DEVELOPER, AI AGENTS We’re looking for an experienced software developer to build and scale the AI agents behind Knak’s platform. In this role you'll develop the agent harness itself: the orchestration, tool calling, context management, and guardrails that let agents analyze data, generate complex marketing assets, and deliver real value to our customers. You'll also ensure we know they work, by building the evaluation suites that measure agent quality and catch regressions before they reach customers. THIS IS A HANDS-ON ROLE FOR SOMEONE WHO WANTS TO BE DEEP IN AGENT INTERNALS EVERY DAY. YOU'LL ALSO CONTRIBUTE TO ARCHITECTURE DECISIONS, MENTOR TEAMMATES, AND COLLABORATE ACROSS ENGINEERING AND PRODUCT TO SHAPE THE FUTURE OF MARKETING AUTOMATION. WHAT YOU’LL BE DOING * Build the agent harness: Design and implement the core agent runtime in Python: orchestration loops, tool definitions and execution, memory and context management, structured outputs, and failure handling. * Own agent evaluations: Build and maintain eval datasets, automated evaluators, and LLM-as-judge pipelines (LangSmith) so every prompt, model, or harness change is measured, not guessed at. * Iterate on agent quality: Diagnose agent failures from traces, tune prompts and tool designs, and run model comparisons and benchmarks to drive measurable improvements. * Create AI microservices: Build Python and Node.js services for agent hosting and LLM interaction. * Build reliable APIs: Develop and maintain the Laravel (PHP) APIs that integrate agents into the Knak platform, ensuring testability, observability, and performance. * Deploy to the cloud: Use AWS services (Lambda, Bedrock, CDN delivery) to build secure, scalable infrastructure for agents. * Optimize databases: Tune MySQL queries and indexing to improve speed and reduce latency. * Elevate code quality: Lead and participate in code reviews, maintaining high standards across the team. * Collaborate cross-functionally: Work with product, design, QA, and DevOps to align solutions with business needs. * Mentor engineers: Share knowledge on agent development and evaluation practices, and set a high bar for technical excellence. WHAT YOU SHOULD BRING * 6+ years of software development experience * Hands-on experience building LLM-powered agents in production, including tool calling, orchestration, context management, and prompt engineering * Experience designing and running evaluations for LLM systems, including dataset curation, automated evaluators, LLM-as-judge, and regression tracking * Strong proficiency in Python, Node.js, and MySQL * Expertise in RESTful APIs, TDD, CI/CD (GitHub Actions) * Experience with SaaS architecture, microservices, and AWS * Knowledge of observability, performance tuning, and scalability * Familiarity with Docker/Kubernetes * Excellent problem-solving skills and a collaborative mindset NICE TO HAVE * Interest in, or experience with, full-stack web development spanning frontend (e.g. Vue), backend (e.g. PHP Laravel), and agent engineering, with a willingness to work across all three as the product needs * Experience in AI-powered product development * Background with LLMs, LangGraph, or AI agent frameworks * Prior experience in a fast-growing SaaS company Base Salary: The anticipated base salary range for this position is $135,000 - 170,000k/year. Final compensation will be determined based on factors including relevant experience, skills, qualifications, and internal equity. This range reflects base salary only and does not include other forms of compensation that may be available as part of the total rewards package. WHAT WE OFFER At Knak we have four foundational pillars. Culture, customers, product and growth. Culture is our number one pillar because we know that is at the core of building a strong company that can build amazing products and delight our customers. We do this with a laser focus on hiring the right people who are smart, positive and who want more than the typical nine-to-five offers. We offer an extremely rewarding, second to none work environment as acknowledged by Ottawa’s Best Places to Work 2026 [https://obj.ca/here-are-the-top-20-best-places-to-work-in-2026/]! We show our investment in our people through our competitive salaries, great benefits, paid vacation, Life leave days (because life happens), team lunches and off-sites, and most importantly our commitment to YOUR career growth. If this sounds like something you’re looking for, then we’d love to hear from you! If you don’t see yourself fully reflected in every job requirement listed on the posting above, we still encourage you to reach out and apply. Research has shown that women and underrepresented groups often only apply when they feel 100% qualified. We strongly encourage applicants of all genders, ages, ethnicities, cultures, abilities, sexual orientations, and life experiences to apply. Knak believes in creating an inclusive, barrier-free working environment. If you require ANY accommodation to the interview process please contact culture@knak.com. At Knak, our recruitment process includes AI screening for keywords and minimum qualifications as well as video interviews which are transcribed with AI. Humans are still at the core of our decision making! Please note that this job post is for an existing vacancy. Click here [https://knak.com/privacy-policy/] to view the Knak Privacy Policy

What you’ll do

You will design and implement the core agent runtime in Python, including orchestration, tool execution, and memory management. Additionally, you will own agent evaluations by building automated pipelines to measure quality and drive improvements.

Requirements

The role requires 6+ years of backend software development experience with hands-on expertise in building LLM-powered agents in production. Proficiency in Python, Node.js, MySQL, and cloud infrastructure is essential for success in this position.

Benefits

• Competitive salaries
• Equity in the company
• Great benefits
• Paid vacation
• Life leave days
• Team lunches
• Off-sites
• Career growth

Listed skills

• Python · Preferred
• Node.js · Preferred
• MySQL · Preferred
• prompt engineering · Preferred
• CI/CD · Preferred
• Amazon Web Services · Preferred

Other relevant skills

Identified from the job description. Confirm important requirements above.

• Python
• Node.js
• MySQL
• LLM
• Prompt engineering
• Orchestration
• Tool calling
• Context management
• RESTful APIs
• TDD
• CI/CD
• AWS
• Microservices
• Observability
• Performance tuning
• Scalability
• Performance Tuning
• Management
• Problem Solving
• Software As A Service (SaaS)
• Decision Making
• Pipelines
• DevOps
• Amazon Web Services
• Artificial Intelligence
• Marketing
• Research
• Application Programming Interface (API)
• Equities
• Python (Programming Language)
• Safety Assurance
• Marketing Automation
• Automation
• Docker (Software)
• RESTful API
• Full Stack Development
• Front End Design
• Node.js (Javascript Library)
• Vue.js (Javascript Library)
• New Product Development
• Code Review
• Software Development
• Prompt Engineering
• Kubernetes
• Github
• Web Development
• Product Design
• PHP (Scripting Language)
• Conversion Marketing
• AI Agents

Job areas

• Software
• Technology
• Engineering
• Marketing
• Data & Analytics
• Software Developer
• Software Developer / Engineer
• Software Developers

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