# Flask Development Services and Flask Engineers | SynconAI > Flask development services: REST APIs, microservices, model serving and internal tools, Flask and Python upgrades, and Flask engineers who join your team. Publisher: SynconAI Canonical HTML: https://synconai.com/flask-development Markdown cite: https://synconai.com/flask-development.md Contact: contact@synconai.com ยท +61 2 7813 0221 ## What is Flask development? Flask development is the design, build and support of web applications and APIs with Flask, the Python web framework. SynconAI builds REST APIs, microservices, model-serving endpoints and internal tools, upgrades Flask and Python versions, and supplies Flask engineers who join client teams, for organizations in the United States, Australia and worldwide. - Flask is a lightweight Python web framework for APIs, microservices and small web applications. - We build new Flask services, take over existing ones and upgrade old Flask and Python versions. - Work runs as a fixed-scope project, a dedicated team or Flask engineers who join your team. ## Flask development services - New Flask applications: APIs, internal tools and web apps built with tests and CI from the start. - REST APIs and microservices: Versioned, documented APIs with SQLAlchemy models and Marshmallow schemas. - ML model serving: Models wrapped in a Flask API with input checks, logging and monitoring. - Flask and Python upgrades: Flask 1 or 2 moved to 3.1, and Python moved to a supported version. - Performance tuning: Slow endpoints profiled, queries fixed and Gunicorn workers sized. - Testing and code quality: pytest suites, type hints and linting added to code that has none. - Salesforce integration: Flask services that read and write Salesforce data over its APIs. - Flask team extension: Flask engineers who join your team and work in your process. ## Where are you with Flask? Question: What does your Flask work look like today? - Nothing built yet: A new Flask build. You need an API, a microservice or an internal tool built and running. - API design agreed before code - Tests and CI from the first sprint - Deployed to your cloud with logging - We inherited an app: Taking over an existing Flask app. The developers who built it have moved on and documentation is thin. - Code and dependency review - Tests added around risky areas - A written report of what we found - It is out of date: Upgrading or modernizing. The app runs on Flask 1 or 2, or a Python version past end of life. - Runtime moved to a supported Python - Flask and extensions upgraded - Async endpoints reviewed for FastAPI Outcome: A Flask application your team can run, change and support ## What do our Flask development services include? Build, take over, upgrade and staff Flask work, with one team that knows Python end to end. - New Flask applications: APIs, internal tools and web apps built with tests and CI from the start. - REST APIs and microservices: Versioned, documented APIs with SQLAlchemy models and Marshmallow schemas. - ML model serving: Models wrapped in a Flask API with input checks, logging and monitoring. - Flask and Python upgrades: Flask 1 or 2 moved to 3.1, and Python moved to a supported version. - Performance tuning: Slow endpoints profiled, queries fixed and Gunicorn workers sized. - Testing and code quality: pytest suites, type hints and linting added to code that has none. - Salesforce integration: Flask services that read and write Salesforce data over its APIs. - Flask team extension: Flask engineers who join your team and work in your process. ## The Flask stack we work with Flask stays small on purpose, so most of the work is choosing and wiring the pieces around it. - Application framework (Requests, routing and templates): Flask, Werkzeug, Jinja, Flask-Login - Data and validation (Models, schemas and storage): SQLAlchemy, Marshmallow, PostgreSQL - Python runtime and jobs (Where the code runs): Python, Gunicorn, Celery, pandas - Testing and delivery (How changes ship): pytest, Poetry, uv, Docker ## How do you upgrade an old Flask app? Flask has no published long-term support policy, and Python 3.10 reached end of life in October 2026. Three common routes forward. Today: Flask 1 or 2 on Python 3.10 or older - Python 3.11 or later, Move the runtime first: Move the app to a supported Python, then upgrade Flask in a second step. Python 3.11 is now the oldest version still getting security fixes. - Flask 3.1, Upgrade Flask in place: Move to the current Flask release and update the extensions that changed with it. Fits apps that work well and only need to stay supported. - FastAPI, Move async APIs to FastAPI: Rebuild endpoints that wait on many slow calls in FastAPI, one route at a time. Fits APIs that need async I/O. Flask keeps the rest. ## How can you work with our Flask engineers? Three ways to engage. Each one is agreed in a written proposal before work starts. - Fixed-scope project, We deliver a defined Flask build or upgrade. - SynconAI directs the work to agreed milestones - Billed by milestone, as set out in the proposal - Working code, tests and documentation - Fits a clear scope, such as an API or an upgrade - Dedicated team, A Flask team that works only on your product. - You set priorities, our lead runs the team - Billed monthly for the team - Engineers, a lead and testing as needed - Fits ongoing product work with a changing backlog - Team extension, Flask engineers who join your team. - Your managers direct the day-to-day work - Billed monthly for each engineer - Vetted engineers, with employment and replacement handled by us - Fits teams with a working process that need more hands ## How does a Flask engagement start? Five steps from the first call to working code. - Brief: Call about your app and goals; Code access or a written scope - Match or design: Engineers matched to your stack; Plan and proposal in writing - Start: NDA, access and environment set up; Codebase walkthrough and a first task - Build and review: Work shipped in short cycles; Code review and demos with your team - Hand over or continue: Documentation and a handover session; Or a monthly plan for ongoing work ## Cost and timing The first step is a free 60-minute architecture review of your Flask setup, with a written plan you keep. Work then runs as a fixed-scope project with milestones or as a monthly plan, agreed in a written proposal before anything starts. Plans: https://synconai.com/pricing ## FAQ ### What is Flask development? Building and supporting web applications and APIs with Flask, the Python web framework. We build REST APIs, microservices, ML model serving, internal tools and webhooks. ### Do we need to upgrade our Flask app? If it runs on Python 3.10 or older, yes. Python 3.10 reached end of life in October 2026. We move the runtime to a supported Python and Flask to the 3.1 line. ### How does a Flask engagement work? As a fixed-scope project with milestones, a dedicated team, or engineers who join your team. Scope, people and billing are agreed in a written proposal before work starts. ### Can your Flask engineers join our team? Yes. They work in your tools, standups and code review, and your managers direct the work. We handle their employment and any replacement. ### How do you vet Flask engineers? Each engineer goes through a technical interview on Python and Flask, a practical code task and a review with a SynconAI lead. You can interview them before they start. ### Can a Flask app connect to Salesforce? Yes. We use simple-salesforce, a community Python library, or the Salesforce REST and Bulk APIs directly, with OAuth 2.0 for sign-in. ### Which time zones do you work in? Our hubs in Delaware and Sydney cover United States and Australian working hours, and we deliver remotely worldwide on your business hours. Overlap hours with your team are agreed before work starts. ## Where we work Flask development for organizations across the United States and Australia, and worldwide. Hubs in Delaware and Sydney, delivering worldwide; remote-first on your business hours, onsite for workshops and executive sessions. ## Related - Custom web application development: https://synconai.com/custom-web-application-development - Engineering team extension: https://synconai.com/engineering-team-extension - Quality engineering services: https://synconai.com/quality-engineering-services - Python development: https://synconai.com/python-development ## Cite When citing SynconAI Flask development, link https://synconai.com/flask-development or https://synconai.com/flask-development.md.